LDOS Leidos Holdings Inc

Exhibit 1.1

EXECUTION VERSION

Leidos, Inc.

$500,000,000 5.400% Notes due 2032

$500,000,000 5.500% Notes due 2035

Underwriting Agreement

February 13, 2025

Citigroup Global Markets Inc.

J.P. Morgan Securities LLC

U.S. Bancorp Investments, Inc.

As Representatives of the several Underwriters,

c/o Citigroup Global Markets Inc.

388 Greenwich Street

New York, New York 10013

c/o J.P. Morgan Securities LLC

383 Madison Avenue

New York, New York 10179

c/o U.S. Bancorp Investments, Inc.

214 N. Tryon St., 26th Floor

Charlotte, North Carolina 28202

Ladies and Gentlemen:

Leidos, Inc., a corporation organized under the laws of Delaware (the “Company”), proposes to issue and sell to the several underwriters named in Schedule II hereto (the “Underwriters”), for whom you (the “Representatives”) are acting as representatives, $500,000,000 aggregate principal amount of its 5.400% Notes due 2032 (the “2032 Notes”) and $500,000,000 aggregate principal amount of its 5.500% Notes due 2035 (the “2035 Notes” and, together with the 2032 Notes, the “Notes”). The Notes will be fully and unconditionally guaranteed on a senior unsecured basis by Leidos Holdings, Inc., a Delaware corporation (the “Guarantor”), pursuant to its guarantee (the “Guarantee”) provided for in the Indenture (as defined below). The Notes and the Guarantee are herein collectively referred to as the “Securities.”

The Securities are to be issued under an indenture (the “Indenture”), dated as of October 8, 2020, among the Company, the Guarantor and Citibank, N.A., as trustee (the “Trustee”). The use of the neuter in this Agreement shall include the feminine and masculine wherever appropriate.

As used in this underwriting agreement (this “Agreement”), the “Registration Statement” means the registration statement referred to in paragraph 1(a) hereof, including the exhibits, schedules and financial statements and any prospectus supplement relating to the Securities that is filed with the Securities and Exchange Commission (the “SEC”) pursuant to Rule 424(b) under the Securities Act of 1933, as amended, and the rules and regulations promulgated thereunder (the “Securities Act”) and deemed part of such registration statement pursuant to Rule 430B under the Securities Act, as amended on each Effective Date, and, in the event any post-effective amendment thereto becomes effective prior to the Closing Date (as defined in Section 3 hereof), shall also mean such registration statement as so amended; the “Effective Date” means each date and time that the Registration Statement and any post-effective amendment or amendments thereto became or becomes effective; the “Base Prospectus” means the base prospectus referred to in paragraph 1(a) hereof contained in the Registration Statement at the date and time that this Agreement is executed and delivered by the parties hereto (the “Execution Time”); a “Preliminary Prospectus” means any preliminary prospectus supplement to the Base Prospectus referred to in paragraph 1(a) hereof which is used prior to the filing of the Final Prospectus, together with the Base Prospectus; and the “Final Prospectus” means the prospectus supplement relating to the Securities that is first filed pursuant to Rule 424(b) under the Securities Act (“Rule 424(b)”) after the Execution Time, together with the Base Prospectus.

Any reference herein to the Registration Statement, the Base Prospectus, any Preliminary Prospectus or the Final Prospectus shall be deemed to refer to and include the documents incorporated by reference therein pursuant to Item 12 of Form S-3 which were filed under the Securities Exchange Act of 1934, as amended, and the rules and regulations promulgated thereunder (the “Exchange Act”) on or before the Effective Date of the Registration Statement or the issue date of the Base Prospectus, any Preliminary Prospectus or the Final Prospectus, as the case may be; and any reference herein to the terms “amend,” “amendment” or “supplement” with respect to the Registration Statement, the Base Prospectus, any Preliminary Prospectus or the Final Prospectus shall be deemed to refer to and include the filing of any document under the Exchange Act after the Effective Date of the Registration Statement or the issue date of the Base Prospectus, any Preliminary Prospectus or the Final Prospectus, as the case may be, deemed to be incorporated therein by reference.

As used in this Agreement, the “Disclosure Package” shall mean (i) the Base Prospectus, (ii) the Preliminary Prospectus used most recently prior to the Execution Time, (iii) any issuer free writing prospectus, as defined in Rule 433 under the Securities Act (an “Issuer Free Writing Prospectus”), identified in Schedule III hereto, (iv) the final term sheet prepared and filed pursuant to Section 5(b) hereto and (v) any other free writing prospectus, as defined in Rule 405 under the Securities Act (a “Free Writing Prospectus”), that the parties hereto shall hereafter expressly agree in writing to treat as part of the Disclosure Package.

1. Representations and Warranties. Each of the Company and the Guarantor, jointly and severally, represents and warrants to, and agrees with, each Underwriter as set forth below in this Section 1.

(a) The Company and the Guarantor meet the requirements for use of Form S-3 under the Securities Act and have prepared and filed with the SEC an automatic shelf registration statement, as defined in Rule 405 under the Securities Act (“Rule 405”) (the file number of which is set forth in Schedule I hereto) on Form S-3, including a related Base Prospectus, for the registration of the offering and sale of the

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Securities under the Securities Act. Such Registration Statement, including any amendments thereto filed prior to the Execution Time, became effective upon filing. The Company may have filed with the SEC, as part of an amendment to the Registration Statement or pursuant to Rule 424(b), preliminary prospectus supplements relating to the Securities, each of which has previously been furnished to you. The Company will file with the SEC a final prospectus supplement relating to the Securities in accordance with Rule 424(b) after the Execution Time. As filed, such final prospectus supplement shall contain all information required by the Securities Act and the rules thereunder and, except to the extent the Representatives shall agree in writing to a modification, shall be in all substantive respects in the form furnished to you prior to the Execution Time or, to the extent not completed at the Execution Time, shall contain only such specific additional information and other changes (beyond that contained in the Base Prospectus and any Preliminary Prospectus) as the Company has advised you, prior to the Execution Time, will be included or made therein. The Registration Statement, at the Execution Time, meets the requirements set forth in Rule 415(a)(1)(x) under the Securities Act. The initial Effective Date of the Registration Statement was not earlier than the date three years before the Execution Time.

(b) On each Effective Date, the Registration Statement did, and when the Final Prospectus is first filed in accordance with Rule 424(b) and on the Closing Date (as defined herein), the Final Prospectus (and any supplement thereto) will, comply in all material respects with the applicable requirements of the Securities Act and the Exchange Act, and the respective rules thereunder, and Trust Indenture Act of 1939, as amended, and the rules and regulations promulgated thereunder (the “Trust Indenture Act”); on each Effective Date, at the Execution Time and on the Closing Date, the Registration Statement did not and will not contain any untrue statement of a material fact or omit to state any material fact required to be stated therein or necessary in order to make the statements therein not misleading; on the Effective Date and on the Closing Date, the Indenture did or will comply in all material respects with the applicable requirements of the Trust Indenture Act and the rules thereunder; and on the date of any filing pursuant to Rule 424(b) and on the Closing Date, the Final Prospectus (together with any supplement thereto) will not include any untrue statement of a material fact or omit to state a material fact necessary in order to make the statements therein, in the light of the circumstances under which they were made, not misleading; provided, however, that the Company makes no representations or warranties as to (i) that part of the Registration Statement which shall constitute the Statement of Eligibility and Qualification (Form T-1) under the Trust Indenture Act of the Trustee or (ii) the information contained in or omitted from the Registration Statement or the Final Prospectus (or any supplement thereto) in reliance upon and in conformity with information furnished in writing to the Company by or on behalf of any Underwriter through the Representatives specifically for inclusion in the Registration Statement or the Final Prospectus (or any supplement thereto), it being understood and agreed that the only such information furnished by any Underwriter consists of the information described as such in Section 8 hereof.

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(c) (i) The Disclosure Package and (ii) any Issuer Free Writing Prospectus, when taken together as a whole with the Disclosure Package, does not contain any untrue statement of a material fact or omit to state any material fact necessary in order to make the statements therein, in the light of the circumstances under which they were made, not misleading. The preceding sentence does not apply to statements in or omissions from the Disclosure Package based upon and in conformity with written information furnished to the Company by any Underwriter through the Representatives specifically for use therein, it being understood and agreed that the only such information furnished by or on behalf of any Underwriter consists of the information described as such in Section 8 hereof.

(d) The documents incorporated by reference in the Disclosure Package and the Final Prospectus, as amended as of the Execution Time, conformed in all material respects to the requirements of the Exchange Act, and none of such documents contained an untrue statement of material fact or omitted to state a material fact necessary to make the statements therein, in light of the circumstances under which they were made, not misleading.

(e) (i) At the time of filing the Registration Statement, (ii) at the time of the most recent amendment thereto for the purposes of complying with Section 10(a)(3) of the Securities Act (whether such amendment was by post-effective amendment, incorporated report filed pursuant to Sections 13 or 15(d) of the Exchange Act or form of prospectus), (iii) at the time the Company or any person acting on its behalf (within the meaning, for this clause only, of Rule 163(c)) made any offer relating to the Securities in reliance on the exemption in Rule 163, and (iv) at the Execution Time (with such date being used as the determination date for purposes of this clause (iv)), the Company was or is (as the case may be) a “well-known seasoned issuer” as defined in Rule 405. The Company agrees to pay the fees required by the SEC relating to the Securities within the time required by Rule 456(b)(1) without regard to the proviso therein and otherwise in accordance with Rules 456(b) and 457(r).

(f) (i) At the earliest time after the filing of the Registration Statement that the Company or another offering participant made a bona fide offer (within the meaning of Rule 164(h)(2)) under the Securities Act and (ii) as of the Execution Time (with such date being used as the determination date for purposes of this clause (ii)), neither the Company nor the Guarantor was or is an Ineligible Issuer (as defined in Rule 405), without taking account of any determination by the SEC pursuant to Rule 405 that it is not necessary that the Company or the Guarantor be considered an Ineligible Issuer.

(g) Each Issuer Free Writing Prospectus does not include any information that conflicts with the information contained in the Registration Statement, including any document incorporated by reference therein and any prospectus supplement deemed to be a part thereof that has not been superseded or modified. The foregoing sentence does not apply to statements in or omissions from any Issuer Free Writing Prospectus based upon and in conformity with written information furnished to the Company by any Underwriter through the Representatives specifically for use therein, it being understood and agreed that the only such information furnished by or on behalf of any Underwriter consists of the information described as such in Section 8 hereof.

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(h) The interactive data in the eXtensible Business Reporting Language (“XBRL”) included as an exhibit to the Registration Statement fairly presents the information called for in all material respects and has been prepared in accordance with the SEC’s rules and guidelines applicable thereto.

(i) Neither the Company nor the Guarantor has paid or agreed to pay to any person any compensation for soliciting another to purchase the Securities (except as contemplated in this Agreement).

(j) Neither the Company nor the Guarantor has taken, directly or indirectly, any action designed to or that has constituted or that might reasonably be expected to cause or result, under the Exchange Act or otherwise, in stabilization or manipulation of the price of any security of the Company or the Guarantor to facilitate the sale or resale of the Securities.

(k) Each of the Guarantor and its “significant subsidiaries” (as defined in Rule 1-02(w) of Regulation S-X) (collectively, the “Significant Subsidiaries”) (i) has been duly organized and is validly existing and in good standing under the laws of the jurisdiction in which it is chartered or organized and (ii) has full corporate power and authority to own or lease, as the case may be, and to operate its properties and conduct its business as described in the Disclosure Package and the Final Prospectus, and is duly qualified to do business and is in good standing under the laws of each jurisdiction in which their respective ownership or lease of property or the conduct of their respective businesses requires such qualification, except where the failure to be so qualified, be in good standing or have such power or authority would not, individually or in the aggregate, have a Material Adverse Effect (as defined below).

(l) The statements in the Preliminary Prospectus and the Final Prospectus under the headings “Material U.S. Federal Income Tax Considerations for Non-U.S. Holders” and “Description of the Notes and Related Guarantee” fairly summarize the matters therein described.

(m) This Agreement has been duly authorized, executed and delivered by the Company and the Guarantor; the Indenture has been duly authorized by the Company and the Guarantor and, assuming due authorization, execution and delivery thereof by the Trustee, when executed and delivered by the Company and the Guarantor, will constitute a legal, valid, binding instrument enforceable against the Company and the Guarantor in accordance with its terms (subject, as to the enforcement of remedies, to applicable bankruptcy, reorganization, insolvency, moratorium or other laws affecting creditors’ rights generally from time to time in effect and to general principles of equity; and the Notes have been duly authorized by the Company, and, when executed and authenticated in accordance with the provisions of the Indenture and delivered to and paid for by the Underwriters, will have been duly executed and delivered by the Company and will constitute the legal, valid and binding obligations of the Company entitled to the benefits of the Indenture (subject, as to the enforcement of remedies, to applicable bankruptcy, reorganization, insolvency, moratorium or other laws affecting creditors’ rights generally from time to time in effect and to general principles of equity).

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(n) No holders of securities of the Company or the Guarantor have rights to the registration of such securities under the Registration Statement.

(o) The Guarantee has been duly authorized by the Guarantor and, when the Indenture has been executed and delivered by the parties thereto on the Closing Date and the Notes have been delivered to and paid for by the Underwriters in accordance with the terms of this Agreement, will constitute the legal, valid, and binding obligations of the Guarantor, enforceable against the Company and the Guarantor in accordance with its terms and entitled to the benefits of the Indenture (subject, as to the enforcement of remedies, to applicable bankruptcy, reorganization, insolvency, moratorium and other laws affecting creditors’ rights generally from time to time in effect and to general principles of equity).

(p) Neither the Company nor the Guarantor is, and, after giving effect to the offering and sale of the Securities and the application of the proceeds thereof as described in the Disclosure Package and the Final Prospectus, will not be an “investment company” as defined in the Investment Company Act of 1940, as amended.

(q) No consent, approval, authorization, filing with or order of any court or governmental agency or body is required in connection with the transactions contemplated herein or in the Indenture, except such as have been obtained under the Securities Act and the Trust Indenture Act and such as may be required under the blue sky laws of any jurisdiction in connection with the purchase and distribution of the Securities by the Underwriters in the manner contemplated herein and in the Disclosure Package and the Final Prospectus.

(r) None of the execution and delivery of this Agreement or the Indenture, the issuance and sale of the Securities, or the consummation of any other of the transactions herein or therein contemplated, or the fulfillment of the terms hereof or thereof will conflict with, result in a breach or violation or imposition of any lien, charge or encumbrance upon any property or assets of the Guarantor or any of its subsidiaries pursuant to, (i) the charter or by-laws or comparable constituting documents of the Guarantor or any of its Significant Subsidiaries; (ii) the terms of any indenture, contract, lease, mortgage, deed of trust, note agreement, loan agreement or other agreement, obligation, condition, covenant or instrument to which the Guarantor or any of its subsidiaries is a party or bound or to which its or their property is subject; or (iii) any statute, law, rule, regulation, judgment, order or decree of any court, regulatory body, administrative agency, governmental body, arbitrator or other authority having jurisdiction over the Guarantor or any of its subsidiaries or any of its or their properties, which conflict, breach, violation or imposition would, in the case of clauses (ii) and (iii) above, either individually or in the aggregate, have a Material Adverse Effect (as defined below).

(s) The consolidated historical financial statements and schedules of the Guarantor and its consolidated subsidiaries included or incorporated by reference in the Preliminary Prospectus, the Final Prospectus and the Registration Statement present fairly in all material respects the financial condition, results of operations and cash flows of the Guarantor as of the dates and for the periods indicated, comply as to form with the applicable accounting requirements of Regulation S-X and have been prepared in conformity with generally accepted accounting principles in the United States of America applied on a consistent basis throughout the periods involved (except as otherwise noted therein).

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(t) No action, suit or proceeding by or before any court or governmental agency, authority or body or any arbitrator involving the Guarantor or any of its subsidiaries or its or their property is pending or, to the best knowledge of the Company or the Guarantor, threatened that (i) would reasonably be expected to have a material adverse effect on the performance by the Company and the Guarantor of their respective obligations under this Agreement or the Indenture or the consummation of any of the transactions contemplated hereby or thereby or (ii) would reasonably be expected to have a material adverse effect on the condition (financial or otherwise), business or results of operations of the Company and its subsidiaries, taken as a whole, whether or not arising from transactions in the ordinary course of business (each of (i) and (ii), a “Material Adverse Effect”), except as set forth in or contemplated in the Disclosure Package and the Final Prospectus (exclusive of any amendment or supplement thereto).

(u) Neither the Company nor any of its Significant Subsidiaries is in violation or default of (i) any provision of its charter or bylaws or comparable constituting documents; (ii) the terms of any indenture, contract, lease, mortgage, deed of trust, note agreement, loan agreement or other agreement, obligation, condition, covenant or instrument to which it is a party or bound or to which its property is subject; or (iii) any statute, law, rule, regulation, judgment, order or decree applicable to the Company or any of its subsidiaries of any court, regulatory body, administrative agency, governmental body, arbitrator or other authority having jurisdiction over the Company or such subsidiary or any of its properties, as applicable, except in the case of clauses (ii) and (iii) above, for such violation or default that would not have a Material Adverse Effect.

(v) Deloitte & Touche LLP, who have certified certain financial statements of the Guarantor and its consolidated subsidiaries and delivered their report with respect to the audited consolidated financial statements and schedules included or incorporated by reference in the Disclosure Package and the Final Prospectus, are independent public accountants with respect to the Guarantor in accordance with applicable accounting rules and within the meaning of the Securities Act.

(w) There are no stamp or other issuance or transfer taxes or duties or other similar fees or charges required to be paid in connection with the execution and delivery of this Agreement or the issuance or sale of the Securities.

(x) Except as set forth in or contemplated in the Disclosure Package and the Final Prospectus (exclusive of any amendment or supplement thereto), (i) the Company and its subsidiaries possess all licenses, certificates, permits and other authorizations issued by all applicable authorities necessary to conduct their respective businesses as described in the Disclosure Package and Final Prospectus (exclusive of any amendment or supplement thereto), except where the failure to possess or to make the same or obtain

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would not, individually or in the aggregate, have a Material Adverse Effect, and (ii) neither the Company nor any of its subsidiaries has received any notice of proceedings relating to the revocation or modification of any such certificate, authorization or permit which, singly or in the aggregate, if the subject of an unfavorable decision, ruling or finding, would have a Material Adverse Effect.

(y) The Guarantor and each of its subsidiaries maintain a system of internal accounting controls sufficient to provide reasonable assurance that (i) transactions are executed in accordance with management’s general or specific authorizations; (ii) transactions are recorded as necessary to permit preparation of financial statements in conformity with generally accepted accounting principles in the United States of America and to maintain asset accountability; (iii) access to assets is permitted only in accordance with management’s general or specific authorization; (iv) the recorded accountability for assets is compared with the existing assets at reasonable intervals and appropriate action is taken with respect to any differences; and (v) the interactive data in XBRL included or incorporated by reference in the Registration Statement, the Preliminary Prospectus and the Final Prospectus is in compliance with the SEC’s published rules, regulations and guidelines applicable thereto. The Guarantor’s internal controls over financial reporting are effective and the Guarantor is not aware of any material weakness in its internal control over financial reporting. The Guarantor and its subsidiaries maintain “disclosure controls and procedures” (as such term is defined in Rule 13a-15(e) under the Exchange Act) and such disclosure controls and procedures are effective.

(z) Except as set forth in the Disclosure Package and the Final Prospectus (exclusive of any amendment or supplement thereto), neither the Company nor any of its subsidiaries: (i) is in violation of, or to the knowledge of the Company has liability or obligations under, any statute, common law, rule, regulation, decision or order of any governmental agency or body or any court, domestic or foreign, relating to the use, disposal or release of hazardous or toxic substances or relating to the protection or restoration of the environment or human exposure to hazardous or toxic substances (collectively, “Environmental Laws”), (ii) owns or operates any real property contaminated with any substance that is subject to any Environmental Laws, or is liable for any off-site disposal or contamination at any location pursuant to any Environmental Laws, (iii) has failed to receive, or is not in compliance with, any permit, license or other approval required of it under applicable Environmental Laws to conduct its respective business, or (iv) is subject to any claim relating to any Environmental Law, nor is the Company aware of any pending investigation or any event or condition that would reasonably be expected to result in any such claim; except, in each case, where any such violation, obligation, contamination, failure, noncompliance, liability or claim would not, individually or in the aggregate, have a Material Adverse Effect.

(aa) Each employee benefit plan, within the meaning of Section 3(3) of the Employee Retirement Income Security Act of 1974, as amended (“ERISA”), that is maintained, administered or contributed to by the Company or any of its affiliates for employees or former employees of the Company and its affiliates has been maintained in substantial compliance with its material terms and the requirements of any applicable statutes, orders, rules and regulations, including but not limited to ERISA and the Code;

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no prohibited transaction, within the meaning of Section 406 of ERISA or Section 4975 of the Code, has occurred with respect to any such plan excluding transactions effected pursuant to a statutory, class or administrative exemption; and for each such plan that is subject to the funding rules of Section 412 of the Code or Section 302 of ERISA, no “accumulated funding deficiency” as defined in Section 412 of the Code has been incurred, whether or not waived, and the fair market value of the assets of each such plan (excluding for these purposes accrued but unpaid contributions) exceeds the present value of all benefits accrued under such plan determined using reasonable actuarial assumptions except as described in the Disclosure Package and the Final Prospectus (exclusive of any amendment or supplement thereto).

(bb) The subsidiaries listed on Annex A attached hereto are the only Significant Subsidiaries of the Company.

(cc) The operations of the Company and its subsidiaries are and have been conducted at all times in compliance in all material respects with applicable financial recordkeeping and reporting requirements and the money laundering statutes and the rules and regulations thereunder and any related or similar rules, regulations or guidelines, issued, administered or enforced by any governmental agency (collectively, the “Money Laundering Laws”) and no action, suit or proceeding by or before any court or governmental agency, authority or body or any arbitrator involving the Company or any of its subsidiaries with respect to the Money Laundering Laws is pending or, to the knowledge of the Company, threatened.

(dd) None of the Company, any of its subsidiaries or, to the knowledge of the Company, any director, officer, agent, employee or affiliate of the Company or any of its subsidiaries (i) is currently subject to any sanctions administered or enforced by the United States Government, including, without limitation, the U.S. State Department, the U.S. Department of the Treasury’s Office of Foreign Assets Control (“OFAC”), the United Nations Security Council, an EU Member State, the European Union, His Majesty’s Treasury, or other relevant sanctions authority (collectively, “Sanctions”) or (ii) is located, organized or resident in a country or territory that is, or whose government is, the subject or target of Sanctions that comprehensively prohibit dealings with that country or territory; and the Company will not directly or indirectly use the proceeds of the offering of the Securities hereunder, or lend, contribute or otherwise make available such proceeds to any subsidiary, joint venture partner or other person or entity, for the purpose of financing the activities of any person subject to any U.S. sanctions administered by OFAC at the time of such financing, or in any manner that would result in a violation of any Sanctions by any individual or entity (including any individual or entity participating in the offering, whether as underwriter, advisor, investor or otherwise).

(ee) There is and has been no failure on the part of the Guarantor or any of the Guarantor’s directors or officers, in their capacities as such, to comply in all material respects with applicable provisions of the Sarbanes-Oxley Act of 2002, as amended, and the rules and regulations promulgated in connection therewith (the “Sarbanes-Oxley Act”), including Section 402 relating to loans and Sections 302 and 906 relating to certifications.

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(ff) Except as disclosed in the Guarantor’s Form 10-K for the year ended January 3, 2025, neither the Guarantor nor any of its subsidiaries nor, to the knowledge of the Company or the Guarantor, any director, officer, agent, employee, affiliate or other person associated with or acting on behalf of the Company, the Guarantor or any of their subsidiaries is aware of or has taken any action, directly or indirectly, that would result in a violation by such persons of the Foreign Corrupt Practices Act of 1977, as amended, and the rules and regulations thereunder (the “FCPA”), including, without limitation, making use of the mails or any means or instrumentality of interstate commerce corruptly in furtherance of an offer, payment, promise to pay or authorization of the payment of any money, or other property, gift, promise to give, or authorization of the giving of anything of value to any “foreign official” (as such term is defined in the FCPA) or any foreign political party or official thereof or any candidate for foreign political office, in contravention of the FCPA; and the Guarantor and its subsidiaries have instituted and maintain policies and procedures designed to ensure, and which are reasonably expected to continue to ensure, continued compliance therewith.

(gg) (i) The Company and its subsidiaries own or possess rights to use all patents, patent applications, trademarks, service marks, trade names, trademark registrations, service mark registrations, copyrights, licenses and know-how (including trade secrets and other unpatented and/or unpatentable proprietary or confidential information, systems or procedures), technology, inventions, designs, processes, methods, technical data and information or other intangible assets or any license or other right to any of the foregoing (collectively, the “Intellectual Property”) used in or otherwise necessary for the conduct of their respective businesses, except for such failures to own or possess as would not have a Material Adverse Effect; and (ii) the conduct of the Company and its subsidiary’s businesses do not violate valid and enforceable rights of others with respect to any Intellectual Property, and the Company and its subsidiaries have not received any notice of or, to the knowledge of the Company and the Guarantor, been threatened with any claim of infringement or conflict with any valid and enforceable rights of others with respect to any Intellectual Property, except, in each case, as would not have a Material Adverse Effect.

(hh) (i) To the Company’s knowledge, there has been no material security breach or incident, unauthorized access or disclosure, or other compromise of or relating to the Company’s or its subsidiaries’ material information technology and computer systems, networks, hardware, software, data and databases (including the data and information of their respective customers, employees, suppliers, vendors and any third party data maintained, processed or stored by the Company and its subsidiaries, and any such data processed or stored by third parties on behalf of the Company and its subsidiaries), equipment or technology (collectively, “IT Systems and Data”), (ii) neither the Company nor its subsidiaries have been notified of, and each of them have no knowledge of any event or condition that could result in, any material security breach or incident, unauthorized access or disclosure or other compromise to their IT Systems and Data, and (iii) the Company and its subsidiaries have implemented appropriate controls,

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policies, procedures, and technological safeguards to maintain and protect the integrity, continuous operation, redundancy and security of their IT Systems and Data reasonably consistent with industry standards and practices, or as required by applicable regulatory standards. The Company and its subsidiaries are presently in material compliance with all applicable laws or statutes and all judgments, orders, rules and regulations of any court or arbitrator or governmental or regulatory authority, internal policies and contractual obligations relating to the privacy and security of IT Systems and Data and to the protection of such IT Systems and Data from unauthorized use, access, misappropriation or modification.

(ii) Any certificate signed by any officer of the Company and the Guarantor and delivered to the Representatives or counsel for the Underwriters in connection with the offering of the Securities shall be deemed a representation and warranty by the Company and the Guarantor, as to matters covered thereby, to each Underwriter.

2. Purchase and Sale. Subject to the terms and conditions and in reliance upon the representations and warranties herein set forth, each of the Company and the Guarantor, severally and not jointly, agrees to sell to each Underwriter, and each Underwriter agrees, severally and not jointly, to purchase from the Company and the Guarantor, at the purchase price set forth in Schedule I hereto, the principal amount of the Notes set forth opposite such Underwriter’s name in Schedule II hereto.

3. Delivery and Payment. Delivery of and payment for the Securities shall be made on the date and at the time specified in Schedule I hereto or at such time on such later date not more than five Business Days after the foregoing date as the Representatives shall designate, which date and time may be postponed by agreement between the Representatives and the Company or as provided in Section 9 hereof (such date and time of delivery and payment for the Securities being herein called the “Closing Date”). As used herein, “Business Day” shall mean any day other than a Saturday, a Sunday or a legal holiday or a day on which banking institutions or trust companies are authorized or obligated by law to close in New York City. Delivery of the Securities shall be made to the Representatives for the respective accounts of the several Underwriters against payment by the several Underwriters through the Representatives of the purchase price thereof to or upon the order of the Company by wire transfer payable in same-day funds to the account specified by the Company. Delivery of the Securities shall be made through the facilities of The Depository Trust Company unless the Representatives shall otherwise instruct.

4. Offering by Underwriters. It is understood that the several Underwriters propose to offer the Securities for sale to the public as set forth in the Final Prospectus.

5. Agreements. Each of the Company and Guarantor agrees with each Underwriter that:

(a) Prior to the termination of the offering of the Securities, the Company will not file any amendment of the Registration Statement or supplement (including the Final Prospectus or any Preliminary Prospectus) to the Base Prospectus unless the Company has furnished you a copy for your review prior to filing and will not file any such proposed amendment or supplement to which you reasonably object. The Company will

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cause the Final Prospectus, properly completed, and any supplement thereto to be filed in a form approved by the Representatives with the SEC pursuant to the applicable paragraph of Rule 424(b) within the time period prescribed and will provide evidence satisfactory to the Representatives of such timely filing. The Company will promptly advise the Representatives (i) when the Final Prospectus, and any supplement thereto, shall have been filed (if required) with the SEC pursuant to Rule 424(b), (ii) when, prior to termination of the offering of the Securities, any amendment to the Registration Statement shall have been filed or become effective, (iii) of any request by the SEC or its staff for any amendment of the Registration Statement, or any Rule 462(b) Registration Statement, or for any supplement to the Final Prospectus or for any additional information, (iv) of the issuance by the SEC of any stop order suspending the effectiveness of the Registration Statement or of any notice objecting to its use or the institution or threatening of any proceeding for that purpose and (v) of the receipt by the Company of any notification with respect to the suspension of the qualification of the Securities for sale in any jurisdiction or the institution or threatening of any proceeding for such purpose. The Company will use its best efforts to prevent the issuance of any such stop order or the occurrence of any such suspension or objection to the use of the Registration Statement and, upon such issuance, occurrence or notice of objection, to obtain as soon as possible the withdrawal of such stop order or relief from such occurrence or objection, including, if necessary, by filing an amendment to the Registration Statement or a new registration statement and using its best efforts to have such amendment or new registration statement declared effective as soon as practicable.

(b) The Company will prepare a final term sheet, containing solely a description of final terms of the Securities and the offering thereof, in the form approved by you and attached as Schedule IV hereto and will file such term sheet pursuant to Rule 433(d) within the time required by such rule.

(c) If, at any time prior to the filing of the Final Prospectus pursuant to Rule 424(b), any event occurs as a result of which the Disclosure Package would include any untrue statement of a material fact or omit to state any material fact necessary to make the statements therein, in the light of the circumstances under which they were made or the circumstances then prevailing, not misleading, or if it should be necessary to amend or supplement the Disclosure Package to comply with applicable law, the Company will promptly (i) notify the Representatives of any such event; (ii) prepare an amendment or supplement that will correct such statement or omission or effect such compliance; and (iii) supply any supplemented or amended Disclosure Package to the Underwriters and counsel for the Underwriters without charge in such quantities as they may reasonably request.

(d) If, at any time when a prospectus relating to the Securities is required to be delivered under the Securities Act (including in circumstances where such requirement may be satisfied pursuant to Rule 172), any event occurs as a result of which the Final Prospectus, as then supplemented, would include any untrue statement of a material fact or omit to state any material fact necessary in order to make the statements therein, in the light of the circumstances under which they were made or the circumstances then prevailing not misleading, or if it shall be necessary to amend the Registration Statement,

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file a new registration statement or supplement the Final Prospectus to comply with the Securities Act or the Exchange Act or the respective rules thereunder, including in connection with use or delivery of the Final Prospectus, the Company promptly will (i) notify the Representatives of any such event, (ii) prepare and file with the SEC, subject to the second sentence of paragraph (a) of this Section 5, an amendment or supplement or new registration statement which will correct such statement or omission or effect such compliance, (iii) use its best efforts to have any amendment to the Registration Statement or new registration statement declared effective as soon as practicable in order to avoid any disruption in use of the Final Prospectus and (iv) supply any supplemented Final Prospectus to the several Underwriters and counsel for the Underwriters without charge in such quantities as they may reasonably request.

(e) As soon as practicable, the Guarantor will make generally available to security holders of the Company and to the Representatives an earnings statement or statements of the Company and its subsidiaries which will satisfy the provisions of Section 11(a) of the Securities Act and Rule 158 under the Securities Act.

(f) The Company and the Guarantor will furnish to the Representatives and counsel for the Underwriters, without charge, signed copies of the Registration Statement (including exhibits thereto) and to each other Underwriter a copy of the Registration Statement (without exhibits thereto) and, so long as delivery of a prospectus by an Underwriter or dealer may be required by the Securities Act (including in circumstances where such requirement may be satisfied pursuant to Rule 172), as many copies of each Preliminary Prospectus, the Final Prospectus and each Issuer Free Writing Prospectus and any supplement thereto as the Representatives may reasonably request. The Company will pay the expenses of printing or other production of all documents relating to the offering.

(g) The Company and the Guarantor will use reasonable best efforts to arrange, if necessary, for the qualification of the Securities for sale by the Underwriters under the laws of such jurisdictions as the Representatives may reasonably designate and will maintain such qualifications in effect so long as required for the sale of the Securities; provided that in no event shall the Company or the Guarantor be obligated (i) to qualify to do business in any jurisdiction where it is not now so qualified, (ii) to take any action that would subject it to service of process in suits, other than those arising out of the offering or sale of the Securities, in any jurisdiction where it is not now so subject or (iii) subject itself to taxation in any such jurisdiction if it is not otherwise so subject. The Company will promptly advise the Representatives of the receipt by the Company or the Guarantor of any notification with respect to the suspension of the qualification of the Securities for sale in any such jurisdiction or the initiation or threatening of any proceeding for such purpose.

(h) The Company will cooperate with the Representatives and use its best efforts to permit the Securities to be eligible for clearance and settlement through The Depository Trust Company.

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(i) During the period from the date hereof through and including the Closing Date, the Company and the Guarantor will not, without the prior written consent of the Representatives, offer, sell, contract to sell, pledge, otherwise dispose of, or enter into any transaction which is designed to, or might reasonably be expected to, result in the disposition (whether by actual disposition or effective economic disposition due to cash settlement or otherwise) by the Company or the Guarantor, directly or indirectly, or announce the offering, of any debt securities issued or guaranteed by the Company or the Guarantor and having a tenor of more than one year (other than the Securities).

(j) Neither the Company nor the Guarantor will take, directly or indirectly, any action designed to, or that has constituted or that might reasonably be expected to, cause or result, under the Exchange Act or otherwise, in stabilization or manipulation of the price of any security of the Company or the Guarantor to facilitate the sale or resale of the Securities.

(k) The Company and the Guarantor, jointly and severally, agree to pay the costs and expenses relating to the following matters: (i) the preparation of the Indenture and the issuance of the Securities; (ii) the preparation, printing or reproduction and filing with the SEC of the Registration Statement (including financial statements and exhibits thereto), each Preliminary Prospectus, the Final Prospectus and each Issuer Free Writing Prospectus, and each amendment or supplement to any of them; (iii) the printing (or reproduction) and delivery (including postage, air freight charges and charges for counting and packaging) of such copies of the Registration Statement, each Preliminary Prospectus, the Final Prospectus and each Issuer Free Writing Prospectus, and all amendments or supplements to any of them, as may, in each case, be reasonably requested for use in connection with the offering and sale of the Securities; (iv) the issuance and delivery of the Securities; (v) any stamp or transfer taxes in connection with the original issuance and sale of the Securities; (vi) the printing (or reproduction) and delivery of this Agreement, any blue sky memorandum and all other agreements or documents printed (or reproduced) and delivered in connection with the offering of the Securities; (vii) any registration or qualification of the Securities for offer and sale under the securities or blue sky laws of the several states (including filing fees and the reasonable and documented fees and expenses of counsel for the Underwriters relating to such registration and qualification); (viii) the transportation and other expenses incurred by or on behalf of Company representatives in connection with presentations to prospective purchasers of the Securities; (ix) the fees and expenses of the Company’s and the Guarantor’s accountants and the fees and expenses of counsel (including local and special counsel) for the Company and the Guarantor; (x) the fees and expenses of the Trustee, including the fees and disbursements of counsel for the Trustee in connection with the Indenture and the Securities; (xi) any fees payable in connection with the rating of the Securities with the ratings agencies; and (xii) all other costs and expenses incident to the performance by the Company and the Guarantor of its obligations hereunder.

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(l) Each of the Company and the Guarantor agree that, unless the Guarantor has or shall have obtained the prior written consent of the Representatives, and each Underwriter, severally and not jointly, agrees with the Company and the Guarantor that, unless it has or shall have obtained, as the case may be, the prior written consent of the Guarantor, it has not made and will not make any offer relating to the Securities that would constitute an Issuer Free Writing Prospectus or that would otherwise constitute a Free Writing Prospectus required to be filed by the Company with the SEC or retained by the Company under Rule 433 under the Securities Act (“Rule 433”), other than a free writing prospectus containing the information contained in the final term sheet specified in Section 5(b) hereto; provided that the prior written consent of the parties hereto shall be deemed to have been given in respect of the Free Writing Prospectuses included in Schedule III hereto and any electronic road show. Any such free writing prospectus consented to by the Representatives or the Company is hereinafter referred to as a “Permitted Free Writing Prospectus.” Each of the Company and the Guarantor agrees that (x) it has treated and will treat, as the case may be, each Permitted Free Writing Prospectus as an Issuer Free Writing Prospectus and (y) it has complied and will comply, as the case may be, with the requirements of Rule 164 under the Securities Act (“Rule 164”) and Rule 433 applicable to any Permitted Free Writing Prospectus, including in respect of timely filing with the SEC, legending and record keeping.

6. Conditions to the Obligations of the Underwriters. The obligations of the Underwriters to purchase the Securities shall be subject to the accuracy of the representations and warranties of the Company and the Guarantor contained herein at the Execution Time and the Closing Date, to the accuracy of the statements of the Company and the Guarantor made in any certificates pursuant to the provisions hereof on and as of the Closing Date, to the performance by the Company and the Guarantor of its obligations hereunder and to the following additional conditions:

(a) The Final Prospectus, and any supplement thereto, have been filed in the manner and within the time period required by Rule 424(b); the final term sheet contemplated by Section 5(b) hereto and any other material required to be filed by the Company pursuant to Rule 433(d) shall have been filed with the SEC within the applicable time periods prescribed for such filings by Rule 433; and no stop order suspending the effectiveness of the Registration Statement or any notice objecting to its use shall have been issued and no proceedings for that purpose shall have been instituted or threatened.

(b) The Company shall have requested and caused Davis Polk & Wardwell LLP, counsel for the Company and the Guarantor, to furnish to the Representatives their written opinion and negative assurance letter, dated the Closing Date and addressed to the Representatives, to the effect set forth in Annex B-I and Annex B-II hereto.

(c) The Representatives shall have received from Cravath, Swaine & Moore LLP, counsel for the Underwriters, such opinion and negative assurance letter, dated the Closing Date and addressed to the Representatives, with respect to the issuance and sale of the Notes, the Guarantee, the Indenture, the Registration Statement, the Disclosure Package, the Final Prospectus and other related matters as the Representatives may reasonably require, and the Company shall have furnished to such counsel such documents as they request for the purpose of enabling them to pass upon such matters.

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(d) Each of the Company and the Guarantor shall have furnished to the Representatives a certificate, signed by (x) its Chairman of the Board, its President or its Chief Executive Officer and (y) its Chief Financial Officer or Principal Accounting Officer, as the case may be, dated the Closing Date, to the effect that the signers of such certificate have carefully examined the Registration Statement, the Disclosure Package and the Final Prospectus and any supplements or amendments thereto, as well as each electronic road show used in connection with the offering of the Securities, and this Agreement and that:

(i) the representations and warranties of such entity in this Agreement are true and correct on and as of the Closing Date with the same effect as if made on the Closing Date, and such entity has complied with all the agreements and satisfied all the conditions on its part to be performed or satisfied hereunder at or prior to the Closing Date;

(ii) no stop order suspending the effectiveness of the Registration Statement or any notice objecting to its use has been issued and no proceedings for that purpose have been instituted or, to the Company’s or the Guarantor’s knowledge, threatened; and

(iii) since the date of the most recent financial statements included or incorporated by reference in the Disclosure Package and the Final Prospectus (exclusive of any amendment or supplement thereto), there has been no material adverse change in the condition (financial or otherwise), business or results of operations of the Company and its subsidiaries, taken as a whole, whether or not arising from transactions in the ordinary course of business, except as set forth in or contemplated in the Disclosure Package and the Final Prospectus (exclusive of any amendment or supplement thereto).

(e) At the Execution Time and at the Closing Date, the Company shall have requested and caused Deloitte & Touche LLP to furnish to the Representatives letters, dated respectively as of the Execution Time and as of the Closing Date, in form and substance satisfactory to the Representatives, containing statements and information of the type ordinarily included in accountant’s “comfort letters” to underwriters with respect to the financial statements and certain financial information contained or incorporated by reference in the Disclosure Package and Final Prospectus, and confirming that they are independent accountants within the meaning of the Securities Act and the Exchange Act and the applicable published rules and regulations thereunder.

(f) Subsequent to the Execution Time or, if earlier, the dates as of which information is given in the Registration Statement and the Final Prospectus (exclusive of any amendment or supplement thereto), there shall not have been (i) any change or decrease specified in the letter or letters referred to in paragraph (f) of this Section 6; or (ii) any change, or any development involving a prospective change, in or affecting the condition (financial or otherwise), prospects, earnings, business or results of operations of the Company and its subsidiaries taken as a whole, whether or not arising from transactions in the ordinary course of business, except as set forth in or contemplated in

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the Disclosure Package and the Final Prospectus (exclusive of any amendment or supplement thereto), the effect of which, in any case referred to in clause (i) or (ii) above, is, in the sole judgment of the Representatives, so material and adverse as to make it impractical or inadvisable to proceed with the offering or delivery of the Securities as contemplated by the Registration Statement (exclusive of any amendment thereof), the Disclosure Package and the Final Prospectus (exclusive of any amendment or supplement thereto).

(g) Subsequent to the Execution Time, there shall not have been any decrease in the rating of any of the Company’s or the Guarantor’s debt securities by any “nationally recognized statistical rating organization” (as defined in Section 3(a)(62) under the Exchange Act) or any notice given of any intended or potential decrease in any such rating or of a possible change in any such rating that does not indicate the direction of the possible change.

(h) Prior to the Closing Date, the Company and the Guarantor shall have furnished to the Representatives such further information, certificates and documents as the Representatives may reasonably request.

If any of the conditions specified in this Section 6 shall not have been fulfilled when and as provided in this Agreement, or if any of the opinions and certificates mentioned above or elsewhere in this Agreement shall not be reasonably satisfactory in form and substance to the Representatives and counsel for the Underwriters, this Agreement and all obligations of the Underwriters hereunder may be cancelled at, or at any time prior to, the Closing Date by the Representatives. Notice of such cancellation shall be given to the Company in writing or by telephone or facsimile confirmed in writing.

The documents required to be delivered by this Section 6 will be delivered at the office of counsel for the Underwriters, at 375 Ninth Avenue, New York, NY 10001, on the Closing Date.

7. Reimbursement of Expenses. If the sale of the Securities provided for herein is not consummated because any condition to the obligations of the Underwriters set forth in Section 6 hereof is not satisfied, because of any termination pursuant to Section 10 hereof or because of any refusal, inability or failure on the part of the Company or the Guarantor to perform any agreement herein or comply with any provision hereof other than by reason of a default by any of the Underwriters, the Company and the Guarantor, jointly and severally, will reimburse the Underwriters severally through the Representatives on demand for all out-of-pocket expenses (including reasonable fees and disbursements of counsel) that shall have been incurred by them in connection with the proposed purchase and sale of the Securities.

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8. Indemnification and Contribution.

(a) Each of the Company and the Guarantor, jointly and severally, agrees to indemnify and hold harmless each Underwriter, the directors, officers, employees, affiliates and agents of each Underwriter and each person who controls any Underwriter within the meaning of either the Securities Act or the Exchange Act against any and all losses, claims, damages or liabilities, joint or several, to which they or any of them may become subject under the Securities Act, the Exchange Act or other U.S. federal or state statutory law or regulation, at common law or otherwise, insofar as such losses, claims, damages or liabilities or actions in respect thereof arise out of or are based upon any untrue statement or alleged untrue statement of a material fact contained in the registration statement for the registration of the Securities as originally filed or in any amendment thereof, or in the Base Prospectus, any Preliminary Prospectus or any other preliminary prospectus supplement relating to the Securities, the Final Prospectus, any Issuer Free Writing Prospectus or the information contained in the final term sheet required to be prepared and filed pursuant to Section 5(b) hereto, or in any amendment thereof or supplement thereto, or arise out of or are based upon the omission or alleged omission to state therein a material fact required to be stated therein or necessary to make the statements therein, in the light of the circumstances under which they were made, not misleading, and agrees to reimburse each such indemnified party, as incurred, for any legal or other expenses reasonably incurred by it in connection with investigating or defending any such loss, claim, damage, liability or action; provided, however, that neither the Company nor the Guarantor will be liable in any such case to the extent that any such loss, claim, damage or liability arises out of or is based upon any such untrue statement or alleged untrue statement or omission or alleged omission made therein in reliance upon and in conformity with written information furnished to the Company by or on behalf of any Underwriter through the Representatives specifically for inclusion therein. This indemnity agreement will be in addition to any liability that the Company or the Guarantor may otherwise have.

(b) Each Underwriter severally, and not jointly, agrees to indemnify and hold harmless the Company and the Guarantor, each of their respective directors and officers who signs the Registration Statement, and each person who controls the Company or the Guarantor within the meaning of either the Securities Act or the Exchange Act, to the same extent as the foregoing indemnity to each Underwriter, but only with reference to written information relating to such Underwriter furnished to the Company by or on behalf of such Underwriter through the Representatives specifically for inclusion in the documents referred to in the foregoing indemnity. This indemnity agreement will be in addition to any liability that any Underwriter may otherwise have. Each of the Company and the Guarantor acknowledges that (i) the statements set forth in the last paragraph of the cover page regarding delivery of the Securities and (ii) under the heading “Underwriting,” the tenth paragraph related to stabilization, syndicate covering transactions and penalty bids and the second and third sentences in the fourth paragraph related to concessions and reallowances in any Preliminary Prospectus and the Final Prospectus constitute the only information furnished in writing by or on behalf of the Underwriters for inclusion in the Preliminary Prospectus, the Final Prospectus or any Issuer Free Writing Prospectus.

(c) Promptly after receipt by an indemnified party under this Section 8 of notice of the commencement of any action, such indemnified party will, if a claim in respect thereof is to be made against the indemnifying party under this Section 8, notify the indemnifying party in writing of the commencement thereof; but the failure so to notify the indemnifying party (i) will not relieve it from liability under paragraph (a) or

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(b) above unless and to the extent it did not otherwise learn of such action and such failure results in the forfeiture by the indemnifying party of substantial rights and defenses and (ii) will not, in any event, relieve the indemnifying party from any obligations to any indemnified party other than the indemnification obligation provided in paragraph (a) or (b) above. The indemnifying party shall be entitled to appoint counsel (including local counsel) of the indemnifying party’s choice at the indemnifying party’s expense to represent the indemnified party in any action for which indemnification is sought (in which case the indemnifying party shall not thereafter be responsible for the fees and expenses of any separate counsel, other than local counsel if not appointed by the indemnifying party, retained by the indemnified party or parties except as set forth below); provided, however, that such counsel shall be reasonably satisfactory to the indemnified party. Notwithstanding the indemnifying party’s election to appoint counsel (including local counsel) to represent the indemnified party in an action, the indemnified party shall have the right to employ separate counsel (including local counsel), and the indemnifying party shall bear the reasonable fees, costs and expenses of such separate counsel if (i) the use of counsel chosen by the indemnifying party to represent the indemnified party would present such counsel with a conflict of interest; (ii) the actual or potential defendants in, or targets of, any such action include both the indemnified party and the indemnifying party and the indemnified party shall have reasonably concluded that there may be legal defenses available to it and/or other indemnified parties that are different from or additional to those available to the indemnifying party; (iii) the indemnifying party shall not have employed counsel reasonably satisfactory to the indemnified party to represent the indemnified party within a reasonable time after notice of the institution of such action; or (iv) the indemnifying party shall authorize the indemnified party to employ separate counsel at the expense of the indemnifying party. The indemnifying party shall not be liable for the fees of more than one separate counsel (in addition to one local counsel in any applicable jurisdiction) for all such indemnified parties. An indemnifying party will not, without the prior written consent of the indemnified parties (which consent shall not be unreasonably withheld), settle or compromise or consent to the entry of any judgment with respect to any pending or threatened claim, action, suit or proceeding in respect of which indemnification or contribution may be sought hereunder (whether or not the indemnified parties are actual or potential parties to such claim or action) unless such settlement, compromise or consent includes an unconditional release of each indemnified party from all liability arising out of such claim, action, suit or proceeding.

(d) In the event that the indemnity provided in paragraph (a) or (b) of this Section 8 is unavailable to or insufficient to hold harmless an indemnified party for any reason, the Company, the Guarantor and the Underwriters severally agree to contribute to the aggregate losses, claims, damages and liabilities (including legal or other expenses reasonably incurred in connection with investigating or defending any loss, claim, damage, liability or action) (collectively “Losses”) to which the Company, the Guarantor and one or more of the Underwriters may be subject in such proportion as is appropriate to reflect the relative benefits received by the Company and the Guarantor, on the one hand, and by the Underwriters on the other from the offering of the Securities; provided, however, that in no case shall any Underwriter be responsible for any amount in excess of the purchase discount or commission applicable to the Securities purchased by such

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Underwriter hereunder. If the allocation provided by the immediately preceding sentence is unavailable for any reason, the Company, the Guarantor and the Underwriters severally shall contribute in such proportion as is appropriate to reflect not only such relative benefits but also the relative fault of the Company and the Guarantor, on the one hand, and the Underwriters on the other in connection with the statements or omissions that resulted in such Losses, as well as any other relevant equitable considerations. Benefits received by the Company and the Guarantor shall be deemed to be equal to the total net proceeds from the offering (before deducting expenses) received by it, and benefits received by the Underwriters shall be deemed to be equal to the total underwriting discounts and commissions, in each case as set forth on the cover page of the Final Prospectus. Relative fault shall be determined by reference to, among other things, whether any untrue or alleged untrue statement of a material fact or the omission or alleged omission to state a material fact relates to information provided by the Company and the Guarantor, on the one hand, or the Underwriters on the other, the intent of the parties and their relative knowledge, access to information and opportunity to correct or prevent such untrue statement or omission. The Company, the Guarantor and the Underwriters agree that it would not be just and equitable if contribution were determined by pro rata allocation or any other method of allocation that does not take account of the equitable considerations referred to above. Notwithstanding the provisions of this paragraph (d), no person guilty of fraudulent misrepresentation (within the meaning of Section 11(f) of the Securities Act) shall be entitled to contribution from any person who was not guilty of such fraudulent misrepresentation. For purposes of this Section 8, each person who controls an Underwriter within the meaning of either the Securities Act or the Exchange Act and each director, officer, employee, affiliate and agent of an Underwriter shall have the same rights to contribution as such Underwriter, and each person who controls the Company or the Guarantor within the meaning of either the Securities Act or the Exchange Act, each officer of the Company and the Guarantor who shall have signed the Registration Statement and each director of the Company and the Guarantor shall have the same rights to contribution as the Company and the Guarantor, subject in each case to the applicable terms and conditions of this paragraph (d).

9. Default by an Underwriter. If any one or more Underwriters shall fail to purchase and pay for any of the Securities agreed to be purchased by such Underwriter hereunder and such failure to purchase shall constitute a default in the performance of its or their obligations under this Agreement, the remaining Underwriters shall be obligated severally to take up and pay for (in the respective proportions which the principal amount of Securities set forth opposite their names in Schedule II hereto bears to the aggregate principal amount of Securities set forth opposite the names of all the remaining Underwriters) the Securities which the defaulting Underwriter or Underwriters agreed but failed to purchase; provided, however, that in the event that the aggregate principal amount of Securities which the defaulting Underwriter or Underwriters agreed but failed to purchase shall exceed 10% of the aggregate principal amount of Securities set forth in Schedule II hereto, the remaining Underwriters shall have the right to purchase all, but shall not be under any obligation to purchase any, of the Securities, and if such nondefaulting Underwriters do not purchase all the Securities, this Agreement will terminate without liability to any nondefaulting Underwriter or the Company and the Guarantor. In the event of a default by any Underwriter as set forth in this Section 9, the Closing Date shall be postponed for such period, not exceeding five Business Days, as the Representatives shall determine in order that the required changes in the Registration Statement and the Final Prospectus or in any other documents or arrangements may be effected. Nothing contained in this Agreement shall relieve any defaulting Underwriter of its liability, if any, to the Company and the Guarantor or any nondefaulting Underwriter for damages occasioned by its default hereunder.

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10. Termination. This Agreement shall be subject to termination in the absolute discretion of the Representatives, by notice given to the Company prior to delivery of and payment for the Securities, if at any time prior to such time (i) trading in securities generally on the New York Stock Exchange shall have been suspended or limited or minimum prices shall have been established on such exchange; (ii) a banking moratorium shall have been declared either by U.S. federal or New York State authorities; or (iii) following the Execution Time, there shall have occurred any outbreak or escalation of hostilities, declaration by the United States of a national emergency or war or other calamity or crisis the effect of which on financial markets is such as to make it, in the sole judgment of the Representatives, impractical or inadvisable to proceed with the offering or delivery of the Securities as contemplated by any Preliminary Prospectus or the Final Prospectus (exclusive of any amendment or supplement thereto).

11. Representations and Indemnities to Survive. The respective agreements, representations, warranties, indemnities and other statements of the Company, the Guarantor, their respective officers and of the Underwriters set forth in or made pursuant to this Agreement will remain in full force and effect, regardless of any investigation made by or on behalf of the Underwriters, the Company, the Guarantor or any of the indemnified persons referred to in Section 8 hereof, and will survive delivery of and payment for the Securities. The provisions of Sections 7 and 8 hereof shall survive the termination or cancellation of this Agreement.

12. Notices. All communications hereunder will be in writing and effective only on receipt, and, if sent to the Representatives, will be mailed, delivered or telefaxed to Citigroup Global Markets Inc. at 388 Greenwich Street, New York, New York 10013, Facsimile: (646) 291-1469, Attention: General Counsel, J.P. Morgan Securities LLC at 383 Madison Avenue, New York, New York 10179, Facsimile: (212) 834-6081, Attention: Investment Grade Syndicate Desk – 3rd floor and to U.S. Bancorp Investments, Inc. at 214 N. Tryon St., 26th Floor Charlotte, North Carolina 28202, Facsimile: (704) 335-2393, Attention: Debt Capital Markets; or, if sent to the Company or the Guarantor, will be mailed, or delivered to Leidos, Inc., 1750 Presidents Street, Reston, Virginia, 20190, Attention: General Counsel.

13. Successors. This Agreement will inure to the benefit of and be binding upon the parties hereto and their respective successors and the indemnified persons referred to in Section 8 hereof and their respective successors, and no other person will have any right or obligation hereunder.

14. Integration. This Agreement supersedes all prior agreements and understandings (whether written or oral) between the Company, the Guarantor and the Underwriters, or any of them, with respect to the subject matter hereof.

15. Applicable Law. This Agreement will be governed by and construed in accordance with the laws of the State of New York applicable to contracts made and to be performed within the State of New York.

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16. Waiver of Jury Trial. Each of the Company and the Guarantor hereby irrevocably waives, to the fullest extent permitted by applicable law, any and all right to trial by jury in any legal proceeding arising out of or relating to this Agreement or the transactions contemplated hereby.

17. No Fiduciary Duty. Each of the Company and the Guarantor hereby acknowledges that (a) the purchase and sale of the Securities pursuant to this Agreement is an arm’s-length commercial transaction between the Company and the Guarantor, on the one hand, and the Underwriters and any affiliate through which it may be acting, on the other, (b) the Underwriters are acting as principal and not as an agent or fiduciary of the Company or the Guarantor and (c) the Company’s and the Guarantor’s engagement of the Underwriters in connection with the offering and the process leading up to the offering is as independent contractors and not in any other capacity. Furthermore, each of the Company and the Guarantor agrees that it is solely responsible for making its own judgments in connection with the offering (irrespective of whether any of the Underwriters has advised or is currently advising the Company or the Guarantor on related or other matters). Each of the Company and the Guarantor agrees that they will not claim that the Underwriters have rendered advisory services of any nature or respect, or owe an agency, fiduciary or similar duty to any of the Company or the Guarantor in connection with such transaction or the process leading thereto.

18. Recognition of the U.S. Special Resolution Regimes.

(a) In the event that any Underwriter that is a Covered Entity becomes subject to a proceeding under a U.S. Special Resolution Regime, the transfer from such Underwriter of this Agreement, and any interest and obligation in or under this Agreement, will be effective to the same extent as the transfer would be effective under the U.S. Special Resolution Regime if this Agreement, and any such interest and obligation, were governed by the laws of the United States or a state of the United States.

(b) In the event that any Underwriter that is a Covered Entity or a BHC Act Affiliate of such Underwriter becomes subject to a proceeding under a U.S. Special Resolution Regime, Default Rights under this Agreement that may be exercised against such Underwriter are permitted to be exercised to no greater extent than such Default Rights could be exercised under the U.S. Special Resolution Regime if this Agreement were governed by the laws of the United States or a state of the United States.

For purposes of Section 18, a “BHC Act Affiliate” has the meaning assigned to the term “affiliate” in, and shall be interpreted in accordance with, 12 U.S.C. § 1841(k); “Covered Entity” means any of the following: (i) a “covered entity” as that term is defined in, and interpreted in accordance with, 12 C.F.R. § 252.82(b), (ii) a “covered bank” as that term is defined in, and interpreted in accordance with, 12 C.F.R. § 47.3(b) or (iii) a “covered FSI” as that term is defined in, and interpreted in accordance with, 12 C.F.R. § 382.2(b); “Default Right” has the meaning assigned to that term in, and shall be interpreted in accordance with, 12 C.F.R. §§ 252.81, 47.2 or 382.1, as applicable; “U.S. Special Resolution Regime” means each of (i) the Federal Deposit Insurance Act and the regulations promulgated thereunder and (ii) Title II of the Dodd-Frank Wall Street Reform and Consumer Protection Act and the regulations promulgated thereunder.

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19. Waiver of Tax Confidentiality. Notwithstanding anything herein to the contrary, purchasers of the Securities (and each employee, representative or other agent of a purchaser) may disclose to any and all persons, without limitation of any kind, the U.S. tax treatment and U.S. tax structure of any transaction contemplated herein and all materials of any kind (including opinions or other tax analyses) that are provided to the purchasers of the Securities relating to such U.S. tax treatment and U.S. tax structure, other than any information for which nondisclosure is reasonably necessary in order to comply with applicable securities laws.

20. Counterparts. This Agreement may be signed in one or more counterparts, each of which shall constitute an original and all of which together shall constitute one and the same agreement.

21. Headings. The section headings used herein are for convenience only and shall not affect the construction hereof.

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If the foregoing is in accordance with your understanding of our agreement, please sign and return to us the enclosed duplicate hereof, whereupon this letter and your acceptance shall represent a binding agreement between the Company, the Guarantor and the several Underwriters.

[Signature Page to Underwriting Agreement]

The foregoing Agreement is hereby

confirmed and accepted as of the date

specified in Schedule I hereto.

Citigroup Global Markets Inc.

J.P. Morgan Securities LLC

U.S. Bancorp Investments, Inc.

Citigroup Global Markets Inc.

J.P. Morgan Securities LLC

U.S. Bancorp Investments, Inc.

For themselves and the other several

Underwriters named in Schedule II to

the foregoing Agreement.

[Signature Page to Underwriting Agreement]

SCHEDULE I

Underwriting Agreement dated February 13, 2025

Registration Statement No. 333-269820

J.P. Morgan Securities LLC

U.S. Bancorp Investments, Inc.

Title, Purchase Price and Description of Securities:

Title: 5.400% Notes due 2032 and 5.500% Notes due 2035

Principal amount: $500,000,000 for the 2032 Notes and $500,000,000 for the 2035 Notes

Purchase price: 99.369% for the 2032 Notes and 98.803% for the 2035 Notes, in each case, plus accrued interest, if any, from February 20, 2025 to the Closing Date

Closing Date, Time and Location: February 20, 2025 at 10:00 a.m. at Cravath, Swaine & Moore LLP, 375 Ninth Avenue, New York, NY 10001

I-1

SCHEDULE II

II-1

SCHEDULE III

Schedule of Free Writing Prospectuses included in the Disclosure Package

III-1

SCHEDULE IV

[Final Term Sheet]

IV-1

Filed Pursuant to Rule 433

Registration No. 333-269820

Issuer Free Writing Prospectus dated February 13, 2025

Relating to Preliminary Prospectus Supplement dated February 13, 2025

LEIDOS, INC.

$500,000,000 5.400% NOTES DUE 2032 (the “2032 Notes”)

$500,000,000 5.500% NOTES DUE 2035 (the “2035 Notes”)

PRICING TERM SHEET

February 13, 2025

IV-2

This communication is intended for the sole use of the person to whom it is provided by us.

IV-3

The issuer and guarantor have filed a registration statement (including a prospectus) with the U.S. Securities and Exchange Commission (the “SEC”) for the offering to which this communication relates. Before you invest, you should read the prospectus in that registration statement, and other documents the issuer and guarantor have filed with the SEC for more complete information about the issuer, the guarantor and this offering. You may get these documents for free by visiting EDGAR on the SEC website at www.sec.gov. Alternatively, the issuer, the guarantor, any underwriter or any dealer participating in this offering will arrange to send you a copy of the prospectus if you request it by calling Citigroup Global Markets Inc. toll-free at 1-800-831-9146, J.P. Morgan Securities LLC collect at (212) 834-4533 or U.S. Bancorp Investments, Inc. toll free at 1-877-558-2607.

Any disclaimer or other notice that may appear below is not applicable to this communication and should be disregarded. Such disclaimer or other notice was automatically generated as a result of this communication being sent via Bloomberg or another email system.

IV-4

Annex A

Significant Subsidiaries

Annex A-1

Exhibit 4.1

LEIDOS, INC.

Officers’ Certificate

February 20, 2025

Reference is made to the Indenture, dated as of October 8, 2020 (the “Indenture”), by and between Leidos, Inc. (the “Issuer”), Leidos Holdings, Inc., the Issuer’s parent company (the “Guarantor”) and Citibank, N.A., as trustee (the “Trustee”). The Trustee is the trustee for any and all securities issued under the Indenture. Pursuant to Section 2.01 and Section 3.01 of the Indenture, the undersigned officers do hereby certify, in connection with the issuance of $500,000,000 aggregate principal amount of 5.400% Notes due 2032 (the “2032 Notes”) and $500,000,000 aggregate principal amount of 5.500% Notes due 2035 (the “2035 Notes” and, together with the 2032 Notes, the “Notes”), that the terms of the Notes are as follows:

Capitalized terms used but not otherwise defined herein shall have the meanings specified in the Indenture.

2

3

Subject to the representations, warranties and covenants described in the Indenture, as amended or supplemented from time to time, the Issuer shall be entitled, subject to authorization by the Board of Directors of the Issuer and an Officers’ Certificate, to issue additional notes from time to time under each series of notes issued hereby. Any such additional notes of a series shall have identical terms as the applicable series of Notes, issued on the issue date, other than with respect to the date of issuance and the issue price (together, the “Additional Notes”). Any Additional Notes will be issued in accordance with Section 3.01 of the Indenture and the provisions set forth in the Appendix.

Such officer has read and understands the provisions of the Indenture and the definitions relating thereto. The statements made in this Officers’ Certificate are based upon the examination of the provisions of the Indenture and upon the relevant books and records of the Issuer. In such officer’s opinion, such officer has made such examination or investigation as is necessary to enable such officer to express an informed opinion as to whether or not the covenants and conditions of such Indenture relating to the issuance and authentication of the Notes have been complied with. In such officer’s opinion, such covenants and conditions have been complied with.

[Signature Page Follows]

IN WITNESS WHEREOF, the undersigned officers of the Issuer have duly executed this certificate as of the date first set forth above.

Exhibit A-1

THIS GLOBAL NOTE IS HELD BY THE DEPOSITARY (AS DEFINED IN THE INDENTURE GOVERNING THIS NOTE) OR ITS NOMINEE IN CUSTODY FOR THE BENEFIT OF THE BENEFICIAL OWNERS HEREOF, AND IS NOT TRANSFERABLE TO ANY PERSON UNDER ANY CIRCUMSTANCES EXCEPT THAT (I) THE TRUSTEE MAY MAKE SUCH NOTATIONS HEREON AS MAYBE REQUIRED PURSUANT TO SECTION 305 OF THE INDENTURE, (II) THIS GLOBAL NOTE MAY BE EXCHANGED IN WHOLE BUT NOT IN PART PURSUANT TO SECTION 305 OF THE INDENTURE, (III) THIS GLOBAL NOTE MAY BE DELIVERED TO THE TRUSTEE FOR CANCELLATION PURSUANT TO SECTION 310 OF THE INDENTURE AND (IV) THIS GLOBAL NOTE MAY BE TRANSFERRED TO A SUCCESSOR DEPOSITARY WITH THE PRIOR WRITTEN CONSENT OF THE COMPANY.

UNLESS THIS CERTIFICATE IS PRESENTED BY AN AUTHORIZED REPRESENTATIVE OF THE DEPOSITORY TRUST COMPANY (“DTC”) TO THE COMPANY OR ITS AGENT FOR REGISTRATION OF TRANSFER, EXCHANGE OR PAYMENT, AND ANY CERTIFICATE ISSUED IS REGISTERED IN THE NAME OF CEDE & CO. OR IN SUCH OTHER NAME AS IS REQUESTED BY AN AUTHORIZED REPRESENTATIVE OF DTC (AND ANY PAYMENT IS MADE TO CEDE & CO. OR TO SUCH OTHER ENTITY AS IS REQUESTED BY AN AUTHORIZED REPRESENTATIVE OF DTC), ANY TRANSFER, PLEDGE OR OTHER USE HEREOF FOR VALUE OR OTHERWISE BY OR TO ANY PERSON IS WRONGFUL INASMUCH AS THE REGISTERED OWNER HEREOF, CEDE & CO., HAS AN INTEREST HEREIN.

LEIDOS, INC.

5.400% Notes due 2032

LEIDOS, INC., a Delaware corporation (the “Issuer”), for value received promises to pay to CEDE & CO. or registered assigns the principal sum of [ ] on March 15, 2032.

Interest Payment Dates: March 15 and September 15 (each, an “Interest Payment Date”), commencing on September 15, 2025.

Interest Record Dates: March 1 and September 1 (each, an “Interest Record Date”).

Reference is made to the further provisions of this Note contained herein, which will for all purposes have the same effect as if set forth at this place.

IN WITNESS WHEREOF, the Issuer has caused this Note to be signed manually or by facsimile by its duly authorized officer.

[Company Signature Page to Global Note No. R-[ ]]

This is one of the Notes of the series designated herein and referred to in the within-mentioned Indenture,

Dated: February 20, 2025

[Signature Page to Global Note No. R-[ ]]

Leidos Holdings, Inc. (“Holdings” or the “Guarantor”) unconditionally guarantees, to the extent set forth in the Indenture and subject to the provisions of the Indenture, the due and punctual payment of the principal of, any premium and interest on the Notes, when and as the same shall become due and payable, whether at maturity, redemption, repayment or otherwise, and the other obligations set forth in, and all in accordance with the terms of Article Thirteen of the Indenture.

The obligations of the undersigned to the Holders of the Notes and to the Trustee pursuant to this Guarantee and in the Indenture are expressly set forth in the Indenture and reference is hereby made to the Indenture for the precise terms of the Guarantee and all of the other provisions of the Indenture to which this Guarantee relates.

IN WITNESS WHEREOF, the Guarantor has caused this Note to be signed manually or by facsimile by its duly authorized officer.

[Guarantor Signature Page to Global Note No. R-[ ]]

(REVERSE OF NOTE)

LEIDOS, INC.

5.400% Notes due 2032

1. Interest

LEIDOS, Inc. (the “Issuer”) promises to pay interest on the principal amount of this Note at the rate per annum described above. Cash interest on the Notes will accrue from the most recent date to which interest has been paid; or, if no interest has been paid, from February 20, 2025. Interest on this Note will be paid to but excluding the relevant Interest Payment Date. The Issuer will pay interest semi-annually in arrears on each Interest Payment Date, commencing September 15, 2025. Interest will be computed on the basis of a 360-day year consisting of twelve 30-day months in a manner consistent with Rule 11620(b) of the NASD Uniform Practice Code.

The Issuer shall pay interest on overdue principal from time to time on demand at the rate borne by the Notes and on overdue installments of interest (without regard to any applicable grace periods) to the extent lawful.

2. Paying Agent.

Initially, Citibank, N.A. (the “Trustee”) will act as paying agent. The Issuer may change any paying agent without notice to the Holders.

3. Indenture; Defined Terms.

This Note is one of the 5.400% Notes due 2032 (the “Notes”) issued under an indenture dated as of October 8, 2020 (the “Base Indenture”) by and between the Issuer, Leidos Holdings, Inc. (the “Guarantor”) and the Trustee, and established pursuant to an Officers’ Certificate dated February 20, 2025, issued pursuant to Section 2.01 and Section 3.01 thereof (together, the “Indenture”). This Note is a “Security” and the Notes are “Securities” under the Indenture.

For purposes of this Note, unless otherwise defined herein, capitalized terms herein are used as defined in the Indenture. The terms of the Notes include those stated in the Indenture and those made part of the Indenture by reference to the Trust Indenture Act of 1939 (15 U.S.C. Sections 77aaa-77bbbb) (the “TIA”) as in effect on the date on which the Indenture was qualified under the TIA. Notwithstanding anything to the contrary herein, the Notes are subject to all such terms, and Holders of Notes are referred to the Indenture and the TIA for a statement of them. To the extent the terms of the Indenture and this Note are inconsistent, the terms of the Indenture shall govern.

4. Guarantee.

The Guarantor has irrevocably, fully and unconditionally guaranteed, on an unsecured and unsubordinated basis, the full and punctual payment (whether at maturity, upon redemption or otherwise) of the principal of and interest on, and all other amounts payable under, the Notes and the full and punctual payment of all other amounts payable by the Issuer under the Indenture and any other obligations of the Issuer under the Indenture, subject to certain terms and conditions set forth in the Indenture.

5. Denominations; Transfer; Exchange.

The Notes are in registered form, without coupons, in denominations of $2,000 and multiples of $1,000 thereafter. A Holder shall register the transfer or exchange of Notes in accordance with the Indenture. The Issuer may require a Holder, among other things, to furnish appropriate endorsements and transfer documents and to pay certain transfer taxes or similar governmental charges payable in connection therewith as permitted by the Indenture. The Issuer need not issue, authenticate, register the transfer of or exchange any Notes or portions thereof for a period of fifteen (15) days before the mailing of a notice of redemption, nor need the Issuer register the transfer or exchange of any Note selected for redemption in whole or in part.

6. Amendment; Supplement; Waiver.

Subject to certain exceptions, the Notes and the provisions of the Indenture relating to the Notes may be amended or supplemented and any existing default or Event of Default or compliance with certain provisions may be waived with the written consent of the Holders of at least a majority in aggregate principal amount of all of the outstanding Notes. Without notice to or consent of any Holder, the parties thereto may amend or supplement the Indenture and the Notes to, among other things, cure any ambiguity, defect or inconsistency or comply with any requirements of the Commission in connection with the qualification of the Indenture under the TIA, or make any other change that does not adversely affect the rights of any Holder of a Note in any material respect.

8. Redemption.

Prior to January 15, 2032 (the “Par Call Date”), the Issuer may redeem the Notes at its option, in whole or in part at any time, or from time to time, at a redemption price (expressed as a percentage of principal amount and rounded to three decimal places) equal to the greater of:

plus, in each case, accrued interest thereon to the date of redemption.

Notwithstanding the foregoing, installments of interest on Notes that are due and payable on Interest Payment Dates falling on or prior to a redemption date will be payable on the Interest Payment Date to the registered Holders as of the close of business on the relevant Interest Record Date according to the Notes and the Indenture. The Trustee shall have no obligation to calculate or verify any calculation of a redemption price.

On or after the Par Call Date, the Issuer may redeem the Notes, in whole or in part, at any time and from time to time, at a redemption price equal to 100% of the principal amount of the Notes being redeemed plus accrued and unpaid interest thereon to the redemption date.

“Treasury Rate” means, with respect to any redemption date, the yield determined by Leidos in accordance with the following two paragraphs.

The Treasury Rate shall be determined by the Issuer after 4:15 p.m., New York City time (or after such time as yields on U.S. government securities are posted daily by the Board of Governors of the Federal Reserve System), on the third Business Day preceding the redemption date based upon the yield or yields for the most recent day that appear after such time on such day in the most recent statistical release published by the Board of Governors of the Federal Reserve System designated as “Selected Interest Rates (Daily)—H.15” (or any successor designation or publication) (“H.15”) under the caption “U.S. government securities–Treasury constant maturities–Nominal” (or any successor caption or heading) (“H.15 TCM”). In determining the Treasury Rate, the Issuer shall select, as applicable: (1) the yield for the Treasury constant maturity on H.15 exactly equal to the period from the redemption date to the Par Call Date (the “Remaining Life”); or (2) if there is no such Treasury constant maturity on H.15 exactly equal to the Remaining Life, the two yields—one yield corresponding to the Treasury constant maturity on H.15 immediately shorter than and one yield corresponding to the Treasury constant maturity on H.15 immediately longer than the Remaining Life—and shall interpolate to the Par Call Date on a straight-line basis (using the actual number of days) using such yields and rounding the result to three decimal places; or (3) if there is no such Treasury constant maturity on H.15 shorter than or longer than the Remaining Life, the yield for the single Treasury constant maturity on H.15 closest to the Remaining Life. For purposes of this paragraph, the applicable Treasury constant maturity or maturities on H.15 shall be deemed to have a maturity date equal to the relevant number of months or years, as applicable, of such Treasury constant maturity from the redemption date.

2

If on the third Business Day preceding the redemption date H.15 TCM is no longer published, the Issuer shall calculate the Treasury Rate based on the rate per annum equal to the semi-annual equivalent yield to maturity at 11:00 a.m., New York City time, on the second Business Day preceding such redemption date of the United States Treasury security maturing on, or with a maturity that is closest to, the Par Call Date, as applicable. If there is no United States Treasury security maturing on the Par Call Date but there are two or more United States Treasury securities with a maturity date equally distant from the Par Call Date, one with a maturity date preceding the Par Call Date and one with a maturity date following the Par Call Date, the Issuer shall select the United States Treasury security with a maturity date preceding the Par Call Date. If there are two or more United States Treasury securities maturing on the Par Call Date or two or more United States Treasury securities meeting the criteria of the preceding sentence, the Issuer shall select from among these two or more United States Treasury securities the United States Treasury security that is trading closest to par based upon the average of the bid and asked prices for such United States Treasury securities at 11:00 a.m., New York City time. In determining the Treasury Rate in accordance with the terms of this paragraph, the semi-annual yield to maturity of the applicable United States Treasury security shall be based upon the average of the bid and asked prices (expressed as a percentage of principal amount) at 11:00 a.m., New York City time, of such United States Treasury security, and rounded to three decimal places. The Trustee shall have no obligation to calculate or verify the redemption price on the Notes.

The Issuer’s actions and determinations in determining the redemption price shall be conclusive and binding for all purposes, absent manifest error.

Notice of any redemption will be mailed or electronically delivered (or otherwise transmitted in accordance with the depositary’s procedures) at least 10 days but not more than 60 days before the redemption date to each Holder of Notes to be redeemed (with a copy to the Trustee), except that redemption notices may be delivered more than 60 days prior to a redemption date if the notice is issued in connection with a defeasance of the Notes or a satisfaction and discharge of the Indenture.

In the case of a partial redemption, selection of the Notes for redemption will be made pro rata, by lot or by such other method as the Trustee in its sole discretion deems appropriate and fair. No Notes of a principal amount of $2,000 or less will be redeemed in part. If any Note is to be redeemed in part only, the notice of redemption that relates to the Note will state any conditions applicable to the redemption and the portion of the principal amount of the Note to be redeemed. A new Note in a principal amount equal to the unredeemed portion of the Note will be issued in the name of the Holder of the Note upon surrender for cancellation of the original Note. For so long as the Notes are held by DTC, Euroclear, Clearstream (or another Depositary), the redemption of the Notes shall be done in accordance with the policies and procedures of the Depositary.

Unless the Issuer defaults in payment of the redemption price, on and after the redemption date interest will cease to accrue on the Notes or portions thereof called for redemption.

9. Offer to Repurchase Upon Change of Control Triggering Event.

If a Change of Control Triggering Event (as defined below) occurs with respect to the Notes, unless the Issuer shall have exercised its right to redeem the Notes as described above, the Issuer shall be required to make an offer to each Holder of Notes to purchase all or any part (equal to $2,000 or an integral multiple of $1,000 in excess thereof) of that Holder’s Notes at a purchase price in cash equal to 101% of the aggregate principal amount thereof, plus accrued and unpaid interest, if any, to the date of purchase (subject to the right of Holders of record on the relevant record date to receive interest due on the relevant Interest Payment Date); provided that after giving effect to the purchase, any Notes that remain outstanding shall have a denomination of $2,000 and integral multiples of $1,000 above that amount.

Within 30 days following the date upon which the Change of Control Triggering Event has occurred or, at the Issuer’s option, prior to any Change of Control (as defined below), but after the public announcement of the transaction that constitutes or may constitute the Change of Control, except to the extent that the Issuer shall have exercised its right to redeem the Notes pursuant to Section 8 hereof, the Issuer shall deliver a notice (a “Change of Control Offer”) to each Holder of Notes with a copy to the Trustee describing the transaction or transactions that constitute or may constitute a Change of Control Triggering Event and offering to purchase Notes on the date specified in the notice, which date will be no earlier than 10 days nor later than 60 days from the date such notice is delivered (other than as may be required by law) (such date, the “Change of Control Payment Date”). The notice will, if delivered prior to the date of consummation of the Change of Control, state that the Change of Control Offer is conditioned on the Change of Control being consummated on or prior to the Change of Control Payment Date specified in the notice.

3

On each Change of Control Payment Date, the Issuer shall, to the extent lawful:

The paying agent will promptly deliver, to each Holder of Notes so tendered the payment for such Notes, and the Trustee shall promptly authenticate and deliver (or cause to be transferred by book entry) to each holder a new Note equal in principal amount to any unpurchased portion of the Notes surrendered, if any.

The Issuer shall comply, to the extent applicable, with the requirements of Rule 14(e)-1 of the Exchange Act and any other securities laws or regulations in connection with the purchase of Notes pursuant to a Change of Control Triggering Event. To the extent that the provisions of any securities laws or regulations conflict with the terms described in the Notes, the Issuer shall comply with the applicable securities laws and regulations and shall not be deemed to have breached its obligations by virtue thereof.

Holders of Notes electing to have Notes purchased pursuant to a Change of Control Offer will be required to surrender their Notes, with the form entitled “Repurchase Exercise Notice Upon a Change of Control” on the reverse of the Note completed, to the paying agent at the address specified in the notice, or transfer their Notes to the paying agent by book-entry transfer pursuant to the applicable procedures of the paying agent, prior to the close of business on the third business day prior to the Change of Control Payment Date.

The Issuer shall not be required to make a Change of Control Offer with respect to the Notes if a third party makes such an offer in the manner, at the times and otherwise in compliance with the requirements for an offer made by the Issuer and such third party purchases all Notes properly tendered and not withdrawn under its offer.

In addition, the Issuer shall not purchase any Notes if there has occurred and is continuing on the Change of Control Payment Date an Event of Default under the Indenture, other than a default in the payment of the change of control payment upon a Change of Control Triggering Event.

If Holders of not less than 95% in aggregate principal amount of the outstanding Notes validly tender and do not withdraw such Notes in a Change of Control Offer and the Issuer, or any third party making a Change of Control Offer in lieu of the Issuer, as described above, purchases all of the Notes validly tendered and not withdrawn by such Holders, the Issuer shall have the right, upon not less than 10 nor more than 60 days’ prior notice, given not more than 30 days following such purchase pursuant to the Change of Control Offer described above, to redeem all Notes that remain outstanding following such purchase at a redemption price in cash equal to 101% of the principal amount thereof, plus accrued and unpaid interest, if any, to the date of redemption (subject to the right of Holders of record on an Interest Record Date to receive interest on the relevant Interest Payment Date).

For purposes of the Change of Control Offer provisions of the Notes, the following definitions are applicable:

“Change of Control” means the occurrence of any one of the following:

4

Notwithstanding the foregoing, a transaction will not be considered to be a Change of Control if (a) the Guarantor becomes a direct or indirect wholly owned subsidiary of a holding company and (b) immediately following that transaction, (1) the direct or indirect holders of the Voting Stock of the holding company are substantially the same as the holders of the Guarantor’s Voting Stock immediately prior to that transaction or (2) no person or group is the beneficial owner, directly or indirectly, of more than 50% of the total voting power of the Voting Stock of the holding company.

“Change of Control Triggering Event” means the occurrence of both a Change of Control and a Ratings Event.

“Investment Grade” means a rating of Baa3 or better by Moody’s (or its equivalent under any successor rating category of Moody’s); a rating of BBB- or better by S&P (or its equivalent under any successor rating category of S&P); and the equivalent investment grade rating from any replacement Rating Agency or Agencies appointed by the Issuer.

“Moody’s” means Moody’s Investors Service, Inc., a subsidiary of Moody’s Corporation, and its successors.

“Rating Agency” means each of Moody’s and S&P; provided, that if either of Moody’s or S&P ceases to rate the Notes or fails to make a rating of the Notes publicly available, the Issuer shall appoint a replacement for such Rating Agency that is a “nationally recognized statistical rating organization” within the meaning of Rule 15c3-1(c)(2)(vi)(F) under the Exchange Act.

“Ratings Event” means the rating on the Notes is lowered by each of the Rating Agencies and such Notes are rated below an Investment Grade by each of the Rating Agencies on any day within the 60-day period (which 60-day period will be extended so long as the rating of the Notes is under publicly announced consideration for a possible downgrade by either of the Rating Agencies) after the earlier of (a) the occurrence of a Change of Control and (b) public notice of the occurrence of a Change of Control or the Issuer’s intention to effect a Change of Control; provided that a Ratings Event will not be deemed to have occurred in respect of a particular Change of Control (and thus will not be deemed a Ratings Event for purposes of the definition of Change of Control Triggering Event) if each Rating Agency making the reduction in rating does not publicly announce or confirm or inform the Trustee in writing at the Issuer’s request that the reduction was the result, in whole or in part, of any event or circumstance comprised of or arising as a result of, or in respect of, the Change of Control (whether or not the applicable Change of Control has occurred at the time of the Ratings Event). If any Rating Agency that provided a rating of a series of Notes on the day immediately prior to the beginning of such 60-day period (or extension thereof) is not providing a rating of such series of Notes at the end of such 60-day period (or extension thereof) for any reason, such 60-day period (or extension thereof) shall be extended an additional 30 days and, if the Issuer has not selected a replacement Rating Agency on or before the end of such 30-day period, then such Rating Agency shall be deemed to have lowered its rating of such series of Notes at the end of such 30- day period to be below an Investment Grade Rating. The Trustee shall have no obligation to monitor ratings on the Notes.

“S&P” means Standard & Poor’s Financial Services LLC, a division of S&P Global Inc., and its successors.

“Voting Stock” of any specified person as of any date means the capital stock of such person that is at the time entitled to vote generally in the election of the board of directors of such person.

10. Defaults and Remedies.

If an Event of Default (other than certain bankruptcy Events of Default with respect to the Issuer, the Guarantor or any material subsidiary of the Issuer) under the Indenture occurs with respect to the Notes and is continuing, then the Trustee may by notice to the Issuer or, the Holders of not less than 25% in aggregate principal amount of all of the outstanding Notes by notice in writing to the Issuer (and to the Trustee if given by Holders), require the Issuer to repay immediately the entire principal amount of all of the outstanding Securities of all series affected, together with all accrued and unpaid interest and premium, if any. If a bankruptcy Event of Default with respect to the Issuer, the Guarantor or any material subsidiary of the Issuer occurs and is continuing, then the entire principal amount of all of the outstanding Securities (including the Notes) will automatically become due immediately and payable without any declaration or other act on the part of the Trustee or any Holder. Holders of Notes may not enforce the Indenture, the Notes or related Guarantees except as provided in the Indenture. The Trustee is not obligated to

5

enforce the Indenture, the Notes or related Guarantees unless it has received indemnity as it reasonably requires. The Indenture permits, subject to certain limitations therein provided, Holders of a majority in aggregate principal amount of all of the outstanding Notes to direct the Trustee in its exercise of any trust or power. The Trustee may withhold from Holders of Notes notice of certain continuing defaults or Events of Default if it determines that withholding notice is in their interest.

11. Authentication.

This Note shall not be valid until the Trustee manually signs the certificate of authentication on this Note.

12. Abbreviations and Defined Terms.

Customary abbreviations may be used in the name of a Holder of a Note or an assignee, such as: TEN COM (= tenants in common), TEN ENT (= tenants by the entireties), JT TEN (= joint tenants with right of survivorship and not as tenants in common), CUST (= Custodian), and U/G/M/A (= Uniform Gifts to Minors Act).

13. CUSIP Numbers.

Pursuant to a recommendation promulgated by the Committee on Uniform Security Identification Procedures, the Issuer has caused CUSIP numbers to be printed on the Notes as a convenience to the Holders of the Notes. No representation is made as to the accuracy of such numbers as printed on the Notes and reliance may be placed only on the other identification numbers printed hereon.

14. Governing Law.

The laws of the State of New York shall govern the Indenture, including the Guarantee, and this Note thereof.

6

ASSIGNMENT FORM

To assign this Note, fill in the form below:

I or we assign and transfer this Note to

(Print or type assignee’s name, address and zip code)

(Insert assignee’s soc. sec. or tax I.D. No.)

and irrevocably appoint          agent to transfer this Note on the books of the Issuer. The agent may substitute another to act for him.

Sign exactly as your name appears on the other side of this Note.

Signature Guarantee:

Signatures must be guaranteed by an “eligible guarantor institution” meeting the requirements of the Registrar, which requirements include membership or participation in the Security Transfer Agent Medallion Program (“STAMP”) or such other “signature guarantee program” as may be determined by the Registrar in addition to, or in substitution for, STAMP, all in accordance with the United States Securities Exchange Act of 1934, as amended.

7

SCHEDULE OF EXCHANGES OF NOTES

The following exchanges of a part of this Global Note for Physical Notes or a part of another Global Note have been made:

8

REPURCHASE EXERCISE NOTICE UPON A CHANGE OF CONTROL

To: Leidos, Inc.

The undersigned registered owner of this Security hereby acknowledges receipt of a notice from Leidos, Inc. (the “Issuer”) as to the occurrence of a Change of Control Triggering Event with respect to the Issuer and hereby directs the Issuer to pay, or cause the Trustee to pay,       an amount in cash equal to 101% of the aggregate principal amount of the Notes, or the portion thereof (which is a multiple of $1,000, provided that the remaining principal amount, if any, following such repurchase shall be at least $2,000 or a multiple of $1,000 in excess thereof) below designated, to be repurchased plus interest accrued to, but excluding, the repurchase date, except as provided in the Indenture.

Dated:      

Signature           

Principal amount to be repurchased (a multiple of $1,000):     

Remaining principal amount following such repurchase:      

(zero or at least $2,000 or a multiple of $1,000 in excess thereof)

By:           

Authorized Signatory

Exhibit A-2

THIS GLOBAL NOTE IS HELD BY THE DEPOSITARY (AS DEFINED IN THE INDENTURE GOVERNING THIS NOTE) OR ITS NOMINEE IN CUSTODY FOR THE BENEFIT OF THE BENEFICIAL OWNERS HEREOF, AND IS NOT TRANSFERABLE TO ANY PERSON UNDER ANY CIRCUMSTANCES EXCEPT THAT (I) THE TRUSTEE MAY MAKE SUCH NOTATIONS HEREON AS MAYBE REQUIRED PURSUANT TO SECTION 305 OF THE INDENTURE, (II) THIS GLOBAL NOTE MAY BE EXCHANGED IN WHOLE BUT NOT IN PART PURSUANT TO SECTION 305 OF THE INDENTURE, (III) THIS GLOBAL NOTE MAY BE DELIVERED TO THE TRUSTEE FOR CANCELLATION PURSUANT TO SECTION 310 OF THE INDENTURE AND (IV) THIS GLOBAL NOTE MAY BE TRANSFERRED TO A SUCCESSOR DEPOSITARY WITH THE PRIOR WRITTEN CONSENT OF THE COMPANY.

UNLESS THIS CERTIFICATE IS PRESENTED BY AN AUTHORIZED REPRESENTATIVE OF THE DEPOSITORY TRUST COMPANY (“DTC”) TO THE COMPANY OR ITS AGENT FOR REGISTRATION OF TRANSFER, EXCHANGE OR PAYMENT, AND ANY CERTIFICATE ISSUED IS REGISTERED IN THE NAME OF CEDE & CO. OR IN SUCH OTHER NAME AS IS REQUESTED BY AN AUTHORIZED REPRESENTATIVE OF DTC (AND ANY PAYMENT IS MADE TO CEDE & CO. OR TO SUCH OTHER ENTITY AS IS REQUESTED BY AN AUTHORIZED REPRESENTATIVE OF DTC), ANY TRANSFER, PLEDGE OR OTHER USE HEREOF FOR VALUE OR OTHERWISE BY OR TO ANY PERSON IS WRONGFUL INASMUCH AS THE REGISTERED OWNER HEREOF, CEDE & CO., HAS AN INTEREST HEREIN.

LEIDOS, INC.

5.500% Notes due 2035

LEIDOS, INC., a Delaware corporation (the “Issuer”), for value received promises to pay to CEDE & CO. or registered assigns the principal sum of [ ] on March 15, 2035.

Interest Payment Dates: March 15 and September 15 (each, an “Interest Payment Date”), commencing on September 15, 2025.

Interest Record Dates: March 1 and September 1 (each, an “Interest Record Date”).

Reference is made to the further provisions of this Note contained herein, which will for all purposes have the same effect as if set forth at this place.

IN WITNESS WHEREOF, the Issuer has caused this Note to be signed manually or by facsimile by its duly authorized officer.

[Company Signature Page to Global Note No. R-[ ]]

This is one of the Notes of the series designated herein and referred to in the within-mentioned Indenture,

Dated: February 20, 2025

[Signature Page to Global Note No. R-[ ]]

Leidos Holdings, Inc. (“Holdings” or the “Guarantor”) unconditionally guarantees, to the extent set forth in the Indenture and subject to the provisions of the Indenture, the due and punctual payment of the principal of, any premium and interest on the Notes, when and as the same shall become due and payable, whether at maturity, redemption, repayment or otherwise, and the other obligations set forth in, and all in accordance with the terms of Article Thirteen of the Indenture.

The obligations of the undersigned to the Holders of the Notes and to the Trustee pursuant to this Guarantee and in the Indenture are expressly set forth in the Indenture and reference is hereby made to the Indenture for the precise terms of the Guarantee and all of the other provisions of the Indenture to which this Guarantee relates.

IN WITNESS WHEREOF, the Guarantor has caused this Note to be signed manually or by facsimile by its duly authorized officer.

[Guarantor Signature Page to Global Note No. R-[ ]]

(REVERSE OF NOTE)

LEIDOS, INC.

5.500% Notes due 2035

1. Interest

LEIDOS, Inc. (the “Issuer”) promises to pay interest on the principal amount of this Note at the rate per annum described above. Cash interest on the Notes will accrue from the most recent date to which interest has been paid; or, if no interest has been paid, from February 20, 2025. Interest on this Note will be paid to but excluding the relevant Interest Payment Date. The Issuer will pay interest semi-annually in arrears on each Interest Payment Date, commencing September 15, 2025. Interest will be computed on the basis of a 360-day year consisting of twelve 30-day months in a manner consistent with Rule 11620(b) of the NASD Uniform Practice Code.

The Issuer shall pay interest on overdue principal from time to time on demand at the rate borne by the Notes and on overdue installments of interest (without regard to any applicable grace periods) to the extent lawful.

2. Paying Agent.

Initially, Citibank, N.A. (the “Trustee”) will act as paying agent. The Issuer may change any paying agent without notice to the Holders.

3. Indenture; Defined Terms.

This Note is one of the 5.500% Notes due 2033 (the “Notes”) issued under an indenture dated as of October 8, 2020 (the “Base Indenture”) by and between the Issuer, Leidos Holdings, Inc. (the “Guarantor”) and the Trustee, and established pursuant to an Officers’ Certificate dated February 20, 2025, issued pursuant to Section 2.01 and Section 3.01 thereof (together, the “Indenture”). This Note is a “Security” and the Notes are “Securities” under the Indenture.

For purposes of this Note, unless otherwise defined herein, capitalized terms herein are used as defined in the Indenture. The terms of the Notes include those stated in the Indenture and those made part of the Indenture by reference to the Trust Indenture Act of 1939 (15 U.S.C. Sections 77aaa-77bbbb) (the “TIA”) as in effect on the date on which the Indenture was qualified under the TIA. Notwithstanding anything to the contrary herein, the Notes are subject to all such terms, and Holders of Notes are referred to the Indenture and the TIA for a statement of them. To the extent the terms of the Indenture and this Note are inconsistent, the terms of the Indenture shall govern.

4. Guarantee.

The Guarantor has irrevocably, fully and unconditionally guaranteed, on an unsecured and unsubordinated basis, the full and punctual payment (whether at maturity, upon redemption or otherwise) of the principal of and interest on, and all other amounts payable under, the Notes and the full and punctual payment of all other amounts payable by the Issuer under the Indenture and any other obligations of the Issuer under the Indenture, subject to certain terms and conditions set forth in the Indenture.

5. Denominations; Transfer; Exchange.

The Notes are in registered form, without coupons, in denominations of $2,000 and multiples of $1,000 thereafter. A Holder shall register the transfer or exchange of Notes in accordance with the Indenture. The Issuer may require a Holder, among other things, to furnish appropriate endorsements and transfer documents and to pay certain transfer taxes or similar governmental charges payable in connection therewith as permitted by the Indenture. The Issuer need not issue, authenticate, register the transfer of or exchange any Notes or portions thereof for a period of fifteen (15) days before the mailing of a notice of redemption, nor need the Issuer register the transfer or exchange of any Note selected for redemption in whole or in part.

6. Amendment; Supplement; Waiver.

Subject to certain exceptions, the Notes and the provisions of the Indenture relating to the Notes may be amended or supplemented and any existing default or Event of Default or compliance with certain provisions may be waived with the written consent of the Holders of at least a majority in aggregate principal amount of all of the outstanding Notes. Without notice to or consent of any Holder, the parties thereto may amend or supplement the Indenture and the Notes to, among other things, cure any ambiguity, defect or inconsistency or comply with any requirements of the Commission in connection with the qualification of the Indenture under the TIA, or make any other change that does not adversely affect the rights of any Holder of a Note in any material respect.

8. Redemption.

Prior to December 15, 2034 (the “Par Call Date”), the Issuer may redeem the Notes at its option, in whole or in part at any time, or from time to time, at a redemption price (expressed as a percentage of principal amount and rounded to three decimal places) equal to the greater of:

plus, in each case, accrued interest thereon to the date of redemption.

Notwithstanding the foregoing, installments of interest on Notes that are due and payable on Interest Payment Dates falling on or prior to a redemption date will be payable on the Interest Payment Date to the registered Holders as of the close of business on the relevant Interest Record Date according to the Notes and the Indenture. The Trustee shall have no obligation to calculate or verify any calculation of a redemption price.

On or after the Par Call Date, the Issuer may redeem the Notes, in whole or in part, at any time and from time to time, at a redemption price equal to 100% of the principal amount of the Notes being redeemed plus accrued and unpaid interest thereon to the redemption date.

“Treasury Rate” means, with respect to any redemption date, the yield determined by Leidos in accordance with the following two paragraphs.

The Treasury Rate shall be determined by the Issuer after 4:15 p.m., New York City time (or after such time as yields on U.S. government securities are posted daily by the Board of Governors of the Federal Reserve System), on the third Business Day preceding the redemption date based upon the yield or yields for the most recent day that appear after such time on such day in the most recent statistical release published by the Board of Governors of the Federal Reserve System designated as “Selected Interest Rates (Daily)—H.15” (or any successor designation or publication) (“H.15”) under the caption “U.S. government securities–Treasury constant maturities–Nominal” (or any successor caption or heading) (“H.15 TCM”). In determining the Treasury Rate, the Issuer shall select, as applicable: (1) the yield for the Treasury constant maturity on H.15 exactly equal to the period from the redemption date to the Par Call Date (the “Remaining Life”); or (2) if there is no such Treasury constant maturity on H.15 exactly equal to the Remaining Life, the two yields—one yield corresponding to the Treasury constant maturity on H.15 immediately shorter than and one yield corresponding to the Treasury constant maturity on H.15 immediately longer than the Remaining Life—and shall interpolate to the Par Call Date on a straight-line basis (using the actual number of days) using such yields and rounding the result to three decimal places; or (3) if there is no such Treasury constant maturity on H.15 shorter than or longer than the Remaining Life, the yield for the single Treasury constant maturity on H.15 closest to the Remaining Life. For purposes of this paragraph, the applicable Treasury constant maturity or maturities on H.15 shall be deemed to have a maturity date equal to the relevant number of months or years, as applicable, of such Treasury constant maturity from the redemption date.

If on the third Business Day preceding the redemption date H.15 TCM is no longer published, the Issuer shall calculate the Treasury Rate based on the rate per annum equal to the semi-annual equivalent yield to maturity at 11:00 a.m., New York City time, on the second Business Day preceding such redemption date of the United States

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Treasury security maturing on, or with a maturity that is closest to, the Par Call Date, as applicable. If there is no United States Treasury security maturing on the Par Call Date but there are two or more United States Treasury securities with a maturity date equally distant from the Par Call Date, one with a maturity date preceding the Par Call Date and one with a maturity date following the Par Call Date, the Issuer shall select the United States Treasury security with a maturity date preceding the Par Call Date. If there are two or more United States Treasury securities maturing on the Par Call Date or two or more United States Treasury securities meeting the criteria of the preceding sentence, the Issuer shall select from among these two or more United States Treasury securities the United States Treasury security that is trading closest to par based upon the average of the bid and asked prices for such United States Treasury securities at 11:00 a.m., New York City time. In determining the Treasury Rate in accordance with the terms of this paragraph, the semi-annual yield to maturity of the applicable United States Treasury security shall be based upon the average of the bid and asked prices (expressed as a percentage of principal amount) at 11:00 a.m., New York City time, of such United States Treasury security, and rounded to three decimal places. The Trustee shall have no obligation to calculate or verify the redemption price on the Notes.

The Issuer’s actions and determinations in determining the redemption price shall be conclusive and binding for all purposes, absent manifest error.

Notice of any redemption will be mailed or electronically delivered (or otherwise transmitted in accordance with the depositary’s procedures) at least 10 days but not more than 60 days before the redemption date to each Holder of Notes to be redeemed (with a copy to the Trustee), except that redemption notices may be delivered more than 60 days prior to a redemption date if the notice is issued in connection with a defeasance of the Notes or a satisfaction and discharge of the Indenture.

In the case of a partial redemption, selection of the Notes for redemption will be made pro rata, by lot or by such other method as the Trustee in its sole discretion deems appropriate and fair. No Notes of a principal amount of $2,000 or less will be redeemed in part. If any Note is to be redeemed in part only, the notice of redemption that relates to the Note will state any conditions applicable to the redemption and the portion of the principal amount of the Note to be redeemed. A new Note in a principal amount equal to the unredeemed portion of the Note will be issued in the name of the Holder of the Note upon surrender for cancellation of the original Note. For so long as the Notes are held by DTC, Euroclear, Clearstream (or another Depositary), the redemption of the Notes shall be done in accordance with the policies and procedures of the Depositary.

Unless the Issuer defaults in payment of the redemption price, on and after the redemption date interest will cease to accrue on the Notes or portions thereof called for redemption.

9. Offer to Repurchase Upon Change of Control Triggering Event.

If a Change of Control Triggering Event (as defined below) occurs with respect to the Notes, unless the Issuer shall have exercised its right to redeem the Notes as described above, the Issuer shall be required to make an offer to each Holder of Notes to purchase all or any part (equal to $2,000 or an integral multiple of $1,000 in excess thereof) of that Holder’s Notes at a purchase price in cash equal to 101% of the aggregate principal amount thereof, plus accrued and unpaid interest, if any, to the date of purchase (subject to the right of Holders of record on the relevant record date to receive interest due on the relevant Interest Payment Date); provided that after giving effect to the purchase, any Notes that remain outstanding shall have a denomination of $2,000 and integral multiples of $1,000 above that amount.

Within 30 days following the date upon which the Change of Control Triggering Event has occurred or, at the Issuer’s option, prior to any Change of Control (as defined below), but after the public announcement of the transaction that constitutes or may constitute the Change of Control, except to the extent that the Issuer shall have exercised its right to redeem the Notes pursuant to Section 8 hereof, the Issuer shall deliver a notice (a “Change of Control Offer”) to each Holder of Notes with a copy to the Trustee describing the transaction or transactions that constitute or may constitute a Change of Control Triggering Event and offering to purchase Notes on the date specified in the notice, which date will be no earlier than 10 days nor later than 60 days from the date such notice is delivered (other than as may be required by law) (such date, the “Change of Control Payment Date”). The notice will, if delivered prior to the date of consummation of the Change of Control, state that the Change of Control Offer is conditioned on the Change of Control being consummated on or prior to the Change of Control Payment Date specified in the notice.

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On each Change of Control Payment Date, the Issuer shall, to the extent lawful:

The paying agent will promptly deliver, to each Holder of Notes so tendered the payment for such Notes, and the Trustee shall promptly authenticate and deliver (or cause to be transferred by book entry) to each holder a new Note equal in principal amount to any unpurchased portion of the Notes surrendered, if any.

The Issuer shall comply, to the extent applicable, with the requirements of Rule 14(e)-1 of the Exchange Act and any other securities laws or regulations in connection with the purchase of Notes pursuant to a Change of Control Triggering Event. To the extent that the provisions of any securities laws or regulations conflict with the terms described in the Notes, the Issuer shall comply with the applicable securities laws and regulations and shall not be deemed to have breached its obligations by virtue thereof.

Holders of Notes electing to have Notes purchased pursuant to a Change of Control Offer will be required to surrender their Notes, with the form entitled “Repurchase Exercise Notice Upon a Change of Control” on the reverse of the Note completed, to the paying agent at the address specified in the notice, or transfer their Notes to the paying agent by book-entry transfer pursuant to the applicable procedures of the paying agent, prior to the close of business on the third business day prior to the Change of Control Payment Date.

The Issuer shall not be required to make a Change of Control Offer with respect to the Notes if a third party makes such an offer in the manner, at the times and otherwise in compliance with the requirements for an offer made by the Issuer and such third party purchases all Notes properly tendered and not withdrawn under its offer.

In addition, the Issuer shall not purchase any Notes if there has occurred and is continuing on the Change of Control Payment Date an Event of Default under the Indenture, other than a default in the payment of the change of control payment upon a Change of Control Triggering Event.

If Holders of not less than 95% in aggregate principal amount of the outstanding Notes validly tender and do not withdraw such Notes in a Change of Control Offer and the Issuer, or any third party making a Change of Control Offer in lieu of the Issuer, as described above, purchases all of the Notes validly tendered and not withdrawn by such Holders, the Issuer shall have the right, upon not less than 10 nor more than 60 days’ prior notice, given not more than 30 days following such purchase pursuant to the Change of Control Offer described above, to redeem all Notes that remain outstanding following such purchase at a redemption price in cash equal to 101% of the principal amount thereof, plus accrued and unpaid interest, if any, to the date of redemption (subject to the right of Holders of record on an Interest Record Date to receive interest on the relevant Interest Payment Date).

For purposes of the Change of Control Offer provisions of the Notes, the following definitions are applicable:

“Change of Control” means the occurrence of any one of the following:

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Notwithstanding the foregoing, a transaction will not be considered to be a Change of Control if (a) the Guarantor becomes a direct or indirect wholly owned subsidiary of a holding company and (b) immediately following that transaction, (1) the direct or indirect holders of the Voting Stock of the holding company are substantially the same as the holders of the Guarantor’s Voting Stock immediately prior to that transaction or (2) no person or group is the beneficial owner, directly or indirectly, of more than 50% of the total voting power of the Voting Stock of the holding company.

“Change of Control Triggering Event” means the occurrence of both a Change of Control and a Ratings Event.

“Investment Grade” means a rating of Baa3 or better by Moody’s (or its equivalent under any successor rating category of Moody’s); a rating of BBB- or better by S&P (or its equivalent under any successor rating category of S&P); and the equivalent investment grade rating from any replacement Rating Agency or Agencies appointed by the Issuer.

“Moody’s” means Moody’s Investors Service, Inc., a subsidiary of Moody’s Corporation, and its successors.

“Rating Agency” means each of Moody’s and S&P; provided, that if either of Moody’s or S&P ceases to rate the Notes or fails to make a rating of the Notes publicly available, the Issuer shall appoint a replacement for such Rating Agency that is a “nationally recognized statistical rating organization” within the meaning of Rule 15c3-1(c)(2)(vi)(F) under the Exchange Act.

“Ratings Event” means the rating on the Notes is lowered by each of the Rating Agencies and such Notes are rated below an Investment Grade by each of the Rating Agencies on any day within the 60-day period (which 60-day period will be extended so long as the rating of the Notes is under publicly announced consideration for a possible downgrade by either of the Rating Agencies) after the earlier of (a) the occurrence of a Change of Control and (b) public notice of the occurrence of a Change of Control or the Issuer’s intention to effect a Change of Control; provided that a Ratings Event will not be deemed to have occurred in respect of a particular Change of Control (and thus will not be deemed a Ratings Event for purposes of the definition of Change of Control Triggering Event) if each Rating Agency making the reduction in rating does not publicly announce or confirm or inform the Trustee in writing at the Issuer’s request that the reduction was the result, in whole or in part, of any event or circumstance comprised of or arising as a result of, or in respect of, the Change of Control (whether or not the applicable Change of Control has occurred at the time of the Ratings Event). If any Rating Agency that provided a rating of a series of Notes on the day immediately prior to the beginning of such 60-day period (or extension thereof) is not providing a rating of such series of Notes at the end of such 60-day period (or extension thereof) for any reason, such 60-day period (or extension thereof) shall be extended an additional 30 days and, if the Issuer has not selected a replacement Rating Agency on or before the end of such 30-day period, then such Rating Agency shall be deemed to have lowered its rating of such series of Notes at the end of such 30- day period to be below an Investment Grade Rating. The Trustee shall have no obligation to monitor ratings on the Notes.

“S&P” means Standard & Poor’s Financial Services LLC, a division of S&P Global Inc., and its successors.

“Voting Stock” of any specified person as of any date means the capital stock of such person that is at the time entitled to vote generally in the election of the board of directors of such person.

10. Defaults and Remedies.

If an Event of Default (other than certain bankruptcy Events of Default with respect to the Issuer, the Guarantor or any material subsidiary of the Issuer) under the Indenture occurs with respect to the Notes and is continuing, then the Trustee may by notice to the Issuer or, the Holders of not less than 25% in aggregate principal amount of all of the outstanding Notes by notice in writing to the Issuer (and to the Trustee if given by Holders), require the Issuer to repay immediately the entire principal amount of all of the outstanding Securities of all series affected, together with all accrued and unpaid interest and premium, if any. If a bankruptcy Event of Default with respect to the Issuer, the Guarantor or any material subsidiary of the Issuer occurs and is continuing, then the entire principal amount of all of the outstanding Securities (including the Notes) will automatically become due immediately and payable without any declaration or other act on the part of the Trustee or any Holder. Holders of Notes may not enforce the Indenture, the Notes or related Guarantees except as provided in the Indenture. The Trustee is not obligated to

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enforce the Indenture, the Notes or related Guarantees unless it has received indemnity as it reasonably requires. The Indenture permits, subject to certain limitations therein provided, Holders of a majority in aggregate principal amount of all of the outstanding Notes to direct the Trustee in its exercise of any trust or power. The Trustee may withhold from Holders of Notes notice of certain continuing defaults or Events of Default if it determines that withholding notice is in their interest.

11. Authentication.

This Note shall not be valid until the Trustee manually signs the certificate of authentication on this Note.

12. Abbreviations and Defined Terms.

Customary abbreviations may be used in the name of a Holder of a Note or an assignee, such as: TEN COM (= tenants in common), TEN ENT (= tenants by the entireties), JT TEN (= joint tenants with right of survivorship and not as tenants in common), CUST (= Custodian), and U/G/M/A (= Uniform Gifts to Minors Act).

13. CUSIP Numbers.

Pursuant to a recommendation promulgated by the Committee on Uniform Security Identification Procedures, the Issuer has caused CUSIP numbers to be printed on the Notes as a convenience to the Holders of the Notes. No representation is made as to the accuracy of such numbers as printed on the Notes and reliance may be placed only on the other identification numbers printed hereon.

14. Governing Law.

The laws of the State of New York shall govern the Indenture, including the Guarantee, and this Note thereof.

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ASSIGNMENT FORM

To assign this Note, fill in the form below:

I or we assign and transfer this Note to

(Print or type assignee’s name, address and zip code)

(Insert assignee’s soc. sec. or tax I.D. No.)

and irrevocably appoint          agent to transfer this Note on the books of the Issuer. The agent may substitute another to act for him.

Sign exactly as your name appears on the other side of this Note.

Signature Guarantee:

Signatures must be guaranteed by an “eligible guarantor institution” meeting the requirements of the Registrar, which requirements include membership or participation in the Security Transfer Agent Medallion Program (“STAMP”) or such other “signature guarantee program” as may be determined by the Registrar in addition to, or in substitution for, STAMP, all in accordance with the United States Securities Exchange Act of 1934, as amended.

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SCHEDULE OF EXCHANGES OF NOTES

The following exchanges of a part of this Global Note for Physical Notes or a part of another Global Note have been made:

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REPURCHASE EXERCISE NOTICE UPON A CHANGE OF CONTROL

To: Leidos, Inc.

The undersigned registered owner of this Security hereby acknowledges receipt of a notice from Leidos, Inc. (the “Issuer”) as to the occurrence of a Change of Control Triggering Event with respect to the Issuer and hereby directs the Issuer to pay, or cause the Trustee to pay,     an amount in cash equal to 101% of the aggregate principal amount of the Notes, or the portion thereof (which is a multiple of $1,000, provided that the remaining principal amount, if any, following such repurchase shall be at least $2,000 or a multiple of $1,000 in excess thereof) below designated, to be repurchased plus interest accrued to, but excluding, the repurchase date, except as provided in the Indenture.

Dated:      

Signature           

Principal amount to be repurchased (a multiple of $1,000):      

Remaining principal amount following such repurchase:       

(zero or at least $2,000 or a multiple of $1,000 in excess thereof)

By:           

Authorized Signatory

Exhibit 5.1

February 20, 2025

Leidos, Inc.

1750 Presidents Street

Reston, VA 20190

Ladies and Gentlemen:

Leidos, Inc., a Delaware corporation (the “Company”) has filed with the Securities and Exchange Commission a Registration Statement on Form S-3 (File No. 333-269820) (the “Registration Statement”) for the purpose of registering under the Securities Act of 1933, as amended (the “Securities Act”), certain securities, including $500,000,000 aggregate principal amount of the Company’s 5.400% Senior Notes due 2032 (the “2032 Notes”) and $500,000,000 aggregate principal amount of the Company’s 5.500% Senior Notes due 2035 (the “2035 Notes” and, together with the 2032 Notes, the “Notes”). The Securities are to be issued pursuant to the provisions of the Indenture dated as of October 8, 2020 (the “Indenture”) between the Company, Leidos Holdings, Inc., a Delaware corporation, as Guarantor (the “Guarantor”), and Citibank, N.A., as trustee (the “Trustee”). The Notes will be guaranteed by the Guarantor (the “Guarantees” and, together with the Notes, the “Securities”). The Securities are to be sold pursuant to the Underwriting Agreement dated February 13, 2025 (the “Underwriting Agreement”) among the Company, the Guarantor and the several underwriters named therein (the “Underwriters”).

We, as your counsel, have examined originals or copies of such documents, corporate records, certificates of public officials and other instruments as we have deemed necessary or advisable for the purpose of rendering this opinion.

In rendering the opinion expressed herein, we have, without independent inquiry or investigation, assumed that (i) all documents submitted to us as originals are authentic and complete, (ii) all documents submitted to us as copies conform to authentic, complete originals, (iii) all signatures on all documents that we reviewed are genuine, (iv) all natural persons executing documents had and have the legal capacity to do so, (v) all statements in certificates of public officials and officers of the Company and the Guarantor that we reviewed were and are accurate and (vi) all representations made by each of the Company and the Guarantors as to matters of fact in the documents that we reviewed were and are accurate.

Based upon the foregoing, and subject to the additional assumptions and qualifications set forth below, we advise you that, in our opinion, when the Notes have been duly executed and authenticated in accordance with the provisions of the Indenture and delivered to and paid for by the Underwriters pursuant to the Underwriting Agreement, the Notes will constitute valid and binding obligations of the Company and the Guarantor, as applicable, enforceable in accordance with their terms, subject to applicable bankruptcy, insolvency and similar laws affecting creditors’ rights generally, concepts of reasonableness and equitable principles of general applicability, provided that we express no opinion as to (x) the effect of fraudulent conveyance, fraudulent transfer or similar provision of applicable law

on the conclusions expressed above or any provision of the Indenture that purports to avoid the effect of fraudulent conveyance, fraudulent transfer or similar provision of applicable law by limiting the amount of any Guarantor’s obligation or (y) the validity, legally binding effect or enforceability of any provision that permits holders to collect any portion of stated principal amount upon acceleration of the Notes to the extent determined to constitute unearned interest.

In connection with the opinion expressed above, we have assumed that the Indenture and the Securities (collectively, the “Documents”) are valid, binding and enforceable agreements of each party thereto (other than as expressly covered above in respect of each of the Company and the Guarantor). We have also assumed that the execution, delivery and performance by each party to each Document to which it is a party (a) are within its corporate powers, (b) do not contravene, or constitute a default under, the certificate of incorporation or bylaws or other constitutive documents of such party, (c) require no action by or in respect of, or filing with, any governmental body, agency or official and (d) do not contravene, or constitute a default under, any provision of applicable law or regulation or any judgment, injunction, order or decree or any agreement or other instrument binding upon such party, provided that we make no such assumption to the extent that we have specifically opined as to such matters with respect to the Company and the Guarantor.

We are members of the Bar of the State of New York and the foregoing opinion is limited to the laws of the State of New York and the General Corporation Law of the State of Delaware, except that we express no opinion as to any law, rule or regulation that is applicable to the Company or the Guarantor, the Documents or such transactions solely because such law, rule or regulation is part of a regulatory regime applicable to any party to any of the Documents or any of its affiliates due to the specific assets or business of such party or such affiliate.

We hereby consent to the filing of this opinion as an exhibit to a report on Form 8-K to be filed by the Company on the date hereof and its incorporation by reference into the Registration Statement and further consent to the reference to our name under the caption “Legal Matters” in the prospectus supplement which is a part of the Registration Statement. In giving this consent, we do not admit that we are in the category of persons whose consent is required under Section 7 of the Securities Act.