NTK Nortek Inc.

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

SCHEDULE TO

(RULE 14d-100)

Tender Offer Statement Pursuant to Section 14(d)(1) or 13(e)(1)

of the Securities Exchange Act of 1934

(Amendment No. 4)

Nortek, Inc.

(Name of Subject Company)

Nevada Corp.

(Offeror)

an indirect wholly owned subsidiary of

Melrose Industries PLC

(Offeror)

(Name of Filing Persons and Offerors)

COMMON STOCK, $0.01 PAR VALUE

(Title of Class of Securities)

656559309

(Cusip Number of Class of Securities)

(Name, Address and Telephone Number of Person Authorized to Receive Notices and Communications on Behalf of Filing Persons)

With copies to:

CALCULATION OF FILING FEE

Check the appropriate boxes below to designate any transactions to which the statement relates:

x           third-party tender offer subject to Rule 14d-1.

o             issue tender offer subject to Rule 13e-4

o             going-private transaction subject to Rule 13e-3

o             amendment to Schedule 13D under Rule 13d-2.

Check the following box if the filing is a final amendment reporting the results of the tender offer.  x

If applicable, check the appropriate box(es) below to designate the appropriate rule provision(s) relied upon:

o             Rule 13e-4(i) (Cross Border Issuer Tender Offer)

o             Rule 14d-1(d) (Cross-Border Third-Party Tender Offer)

This Amendment No. 4 (this “ Amendment ”) amends and supplements the Tender Offer Statement on Schedule TO (together with any previous or subsequent amendments and supplements thereto, the “ Schedule TO ”) filed with the Securities and Exchange Commission on July 8, 2016 by Nevada Corp., a Delaware corporation (“ Purchaser ”) and an indirect wholly owned subsidiary of Melrose Industries PLC (“ Parent ”), a public limited company incorporated under the laws of the United Kingdom and registered in England and Wales with registered number 9800044, in connection with Purchaser’s offer to purchase all of the outstanding shares of common stock, par value $0.01 per share (the “ Shares ”), of Nortek, Inc. (the “ Company ”), a Delaware corporation, at a price of $86.00 per Share, in cash, without interest, subject to any withholding of taxes required by applicable law, upon the terms and subject to the conditions described in the offer to purchase, dated July 8, 2016 (as it may be amended or supplemented from time to time, the “ Offer to Purchase ”), and in the related letter of transmittal (as it may be amended or supplemented from time to time, the “ Letter of Transmittal ”), copies of which are included as Exhibits (a)(1)(i) and (a)(1)(ii), respectively, to the Schedule TO (which, together with any amendments or supplements thereto, collectively constitute the “ Offer ”).

All information in the Offer to Purchase and the related Letter of Transmittal, which were previously filed as Exhibits (a)(1)(i) and (a)(1)(ii), respectively, to the Schedule TO, is hereby expressly incorporated in this Amendment by reference to all of the applicable items in the Schedule TO, except that such information is amended and supplemented to the extent specifically provided in this Amendment.  Capitalized terms used and not otherwise defined in this Amendment shall have the meanings assigned to such terms in the Offer to Purchase or in the Schedule TO.

Items 4.  Terms of the Transaction.

Item 4 of the Schedule TO is hereby amended and supplemented by adding the following at the end of the section entitled “Section 1—Terms of the Offer” of the Offer to Purchase:

“The Offer and withdrawal rights expired as scheduled at 2:00 a.m., Eastern time, on August 31, 2016 and were not extended. On August 31, 2016, Parent issued a press release announcing that the Depositary has advised Parent that, as of the Expiration Date, a total of 14,860,844 Shares were validly tendered into and not withdrawn from the Offer (excluding Shares tendered pursuant to guaranteed delivery instructions for which certificates were not actually delivered prior to the Expiration Date), representing approximately 93% of the currently issued and outstanding Shares. Accordingly, the number of Shares tendered into the Offer has satisfied the Minimum Condition. In addition, Notices of Guaranteed Delivery have been delivered with respect to 188,012 Shares.

All conditions to the Offer having been satisfied, Purchaser has accepted for payment, and has paid for, all Shares validly tendered and not validly withdrawn on or prior to the Expiration Date.

Following the consummation of the Offer, Purchaser effected the Merger of Purchaser with and into the Company in accordance with Section 251(h) of the DGCL, without a vote of the stockholders of the Company.  At the Effective Time, each Share issued and outstanding immediately prior to the Effective Time was converted into the right to receive cash in an amount equal to the Offer Price, without interest, subject to any withholding of taxes required by applicable law, except as provided in the Merger Agreement with respect to Shares owned by Parent or the Purchaser or held in treasury by the Company or Shares held by any stockholder who is entitled to demand and properly has demanded appraisal for such Shares in accordance and full compliance with Section 262 of the DGCL.

Parent intends to promptly cause all Shares of the Company to be delisted from the NASDAQ Stock Market and deregistered under the Exchange Act.

The press release issued by Parent announcing the expiration of the Offer and the acceptance of Shares for payment is filed as Exhibit (a)(5)(iv) to the Schedule TO and is incorporated herein by reference.”

Item 12.  Exhibits.

Item 12 of the Schedule TO is hereby amended and supplemented by adding the following exhibit:

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SIGNATURE

After due inquiry and to the best of my knowledge and belief, I certify that the information set forth in this statement is true, complete and correct.

Dated: August 31, 2016

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