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Notice of Special Meeting of Star Maritime Acquisition Corp. Stockholders
To Be Held on                        , 2007

To Star Maritime Stockholders:

        A special meeting of stockholders of Star Maritime Acquisition Corp., a Delaware corporation, or Star Maritime, will be held at the offices of Seward & Kissel LLP, One Battery Park Plaza, 23 ^rd Floor, New York, New York on            , 2007, at 10:00 a.m., for the following purposes:

1.    To consider and vote upon a proposal to approve and authorize the acquisition of eight drybulk carriers by Star Bulk Carriers Corp., or Star Bulk, a wholly-owned Marshall Islands subsidiary of Star Maritime, from certain wholly-owned subsidiaries of TMT Co., Ltd., or TMT, pursuant to definitive agreements, for an aggregate purchase price of $345,237,520, consisting of $224,500,000 in cash and 12,537,645 shares of common stock of Star Bulk to be issued at the time of the Redomiciliation Merger and an additional 1,606,962 shares of common stock of Star Bulk to be issued in two installments, which we refer to as the Asset Acquisition. Star Maritime has also entered into related agreements with TMT in connection with the Asset Acquisition.

2.    To consider and vote upon a proposal to approve and authorize the merger, which we refer to as the Redomiciliation Merger, pursuant to the Agreement and Plan of Merger, dated March 14, 2007, by and between Star Maritime and its wholly-owned Marshall Islands subsidiary, Star Bulk Carriers Corp., or Star Bulk, whereby Star Maritime will merge with and into Star Bulk, with Star Bulk as the surviving corporation. As a result of the Redomiciliation Merger: (i) the separate corporate existence of Star Maritime will cease; (ii) each share of Star Maritime common stock, par value $0.0001 per share, will be converted into the right to receive one share of Star Bulk common stock, par value $0.01 per share; and (iii) each outstanding warrant of Star Maritime will be assumed by Star Bulk with the same terms and restrictions, except that each will be exerciseable for common stock of Star Bulk, all as more particularly described in the joint proxy statement/prospectus. The approval of the Asset Acquisition is conditioned upon the approval of the Redomiciliation Merger. Star Bulk cannot complete the Asset Acquisition unless the Redomiciliation Merger is approved and completed; and

3.    To adjourn the special meeting in the event Star Maritime has not received the requisite shareholder vote to approve the Asset Acquisition and the Redomiciliation Merger.

        As of October 9, 2007, there were 29,026,924 shares of Star Maritime common stock issued and outstanding and entitled to vote. Only Star Maritime stockholders who hold shares of record as of the close of business on            , 2007 are entitled to vote at the special meeting or any adjournment or postponement of the special meeting. Approval of the Asset Acquisition is conditioned upon approval of the Redomiciliation Merger. Star Bulk cannot complete the Asset Acquisition unless the Redomiciliation Merger is approved and completed. Star Maritime cannot complete the Redomiciliation Merger unless: (1) the holders of at least a majority of the issued and outstanding shares of Star Maritime entitled to vote at the special meeting vote in favor of the Redomiciliation Merger; (2) holders of at least a majority of the shares of common stock issued in the initial public offering and the private placement vote in favor of the Redomiciliation Merger; and (3) holders of less than 6,600,000 shares of common stock, such number representing 33.0% of the 20,000,000 shares of Star Maritime common stock issued in the initial public offering and private placement, vote against the Redomiciliation Merger and exercise their redemption rights to have their shares redeemed for cash. Holders of shares of Star Maritime common stock have the right to redeem such shares for cash if such stockholder votes against the Redomiciliation Merger and, at the same time, demands that Star Maritime redeem such shares for cash and the Redomiciliation Merger is approved and completed. The actual per share redemption price will be calculated two business days prior to the consummation of

the Redomiciliation Merger. The redemption price would have been $10.39 per share, based on funds in the Trust Account as of June 30, 2007. In order to exercise redemption rights, an eligible stockholder must vote against the Redomiciliation Merger and elect to exercise redemption rights on the enclosed proxy card. If a stockholder votes against the Redomiciliation Merger but fails to properly exercise redemption rights, such stockholder will not be entitled to have its shares redeemed for cash. Any request for redemption, once made, may be withdrawn at any time up to the date of the special meeting.

        Holders of Star Maritime's stock will not be entitled to any appraisal rights under the Delaware General Corporation Law in connection with the Redomiciliation Merger.

        Whether or not you plan to attend the special meeting in person, please submit your proxy card without delay. Voting by proxy will not prevent you from voting your shares in person if you subsequently choose to attend the special meeting. If you fail to return your proxy card, the effect will be that your shares will not be counted for purposes of determining whether a quorum is present at the special meeting and will have the same effect as a vote "against" the approval and authorization of the Asset Acquisition and the Redomiciliation Merger. You may revoke a proxy at any time before it is voted at the special meeting by executing and returning a proxy card dated later than the previous one, by attending the special meeting in person and casting your vote by ballot or by submitting a written revocation to Star Maritime at 103 Foulk Road, Wilmington, Delaware 19803, Attention: Corporate Secretary, before we take the vote at the special meeting. If you hold your shares through a bank or brokerage firm, you should follow the instructions of your bank or brokerage firm regarding revocation of proxies.

         Star Maritime's board of directors unanimously recommends that Star Maritime stockholders vote "FOR" approval of the Asset Acquisition and the Redomiciliation Merger.

Wilmington, Delaware
                        , 2007

TABLE OF CONTENTS

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QUESTIONS AND ANSWERS ABOUT THE STAR MARITIME SPECIAL MEETING

Q:

What is the purpose of this document?

A:

This document serves as Star Maritime's proxy statement and as the prospectus of Star Bulk. As a proxy statement, this document is being provided to Star Maritime stockholders because the Star Maritime board of directors is soliciting their proxies to vote to approve, at a special meeting of stockholders, (i) the acquisition of eight drybulk carriers by Star Bulk, a wholly-owned Marshall Islands subsidiary of Star Maritime, from certain wholly-owned subsidiaries of TMT pursuant to definitive agreements, for an aggregate purchase price of $345,237,520, consisting of $224,500,000 in cash and 12,537,645 shares of common stock of Star Bulk to be issued at the time of Redomiciliation Merger and an additional 1,606,962 shares of common stock of Star Bulk to be issued in two installments; and (ii) the merger of Star Maritime with and into Star Bulk, with Star Bulk as the surviving corporation. The approval of the Asset Acquisition is conditioned upon the approval of the Redomiciliation Merger. As a prospectus, Star Bulk is providing this document to Star Maritime stockholders because Star Bulk is offering its shares in exchange for shares of Star Maritime common stock and Star Bulk is assuming the outstanding warrants of Star Maritime in the Redomiciliation Merger. The registration statement on Form F-1/F-4 of which this joint proxy statement/prospectus is a part is being filed by Star Bulk to register the shares being offered in exchange for shares of Star Maritime, the 20,000,000 warrants of Star Maritime that will be assumed by Star Bulk, the 20,000,000 shares of Star Bulk common stock issuable upon exercise of such warrants and to register an additional 14,144,607 shares of common stock that Star Bulk will issue to TMT or subsequently to TMT's affiliates in respect of the stock consideration portion of the aggregate purchase price of the vessels in the initial fleet. The shares of common stock that Star Bulk will issue in exchange for shares of Star Maritime are referred to herein as the Merger Consideration.

Q:

What matters will we be asked to vote on at the Star Maritime special meeting?

A:

There are three proposals on which you are being asked to vote. At the special meeting, you will be asked to consider and vote upon a proposal to approve and authorize (i) the acquisition of eight drybulk carriers by Star Bulk, a wholly-owned Marshall Islands subsidiary of Star Maritime, from certain wholly-owned subsidiaries of TMT pursuant to definitive agreements, for an aggregate purchase price of $345,237,520, consisting of $224,500,000 in cash and 12,537,645 shares of common stock of Star Bulk to be issued at the time of Redomiciliation Merger and an additional 1,606,962 shares of common stock of Star Bulk to be issued in two installments; (ii) the merger of Star Maritime with and into Star Bulk, with Star Bulk as the surviving corporation and (iii) to approve the adjournment of the special meeting in order to solicit additional proxies in the event that Star Maritime has not obtained the requisite shareholder approval of the Asset Acquisition and the Redomiciliation Merger. As a result of the Redomiciliation Merger (i) the separate corporate existence of Star Maritime will cease; (ii) each outstanding share of Star Maritime common stock, par value $0.0001 per share, will be converted into the right to receive one share of Star Bulk common stock, par value $0.01 per share; and (iii) each outstanding warrant of Star Maritime will be assumed by Star Bulk with the same terms and restrictions, except that each will be exercisable for common stock of Star Bulk. Approval of the Asset Acquisition is conditioned upon approval of the Redomiciliation Merger. Star Maritime cannot complete the Asset Acquisition unless the Redomiciliation Merger is approved and completed.

Q:

Could you tell me more about the definitive agreements to acquire the vessels?

A:

Star Bulk will acquire the fleet of eight drybulk carriers pursuant to separate memoranda of agreement, which we collectively refer to as the MOAs, by and between Star Bulk and the vessel-owning subsidiaries of TMT, each as supplemented by a Supplemental Agreement by and among Star Maritime, Star Bulk and TMT, and a Master Agreement by and among Star Maritime, Star

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Bulk and TMT. We refer to the MOAs, the Supplemental Agreement and the Master Agreement collectively as the Acquisition Agreements. The acquisition of the vessels by Star Bulk is contingent upon, among other things, the approval and consummation of the Redomiciliation Merger. Copies of the MOAs are attached to this joint proxy statement/prospectus as Appendices A-H. A copy of the Supplemental Agreement is attached to this joint proxy statement/prospectus as Appendix I. A copy of the Master Agreement is attached to this joint proxy statement/prospectus as Appendix J.

Q:

Could you tell me more about the parties to the Acquisition Agreements?

A:

Star Maritime was organized under the laws of the State of Delaware on May 13, 2005 and is a Business Combination Company™, or BCC™, which is a blank check company formed to acquire, through a merger, capital stock exchange, asset acquisition or similar business combination, one or more target businesses in the shipping industry. A target business includes one or more entities with agreements to acquire vessels or an operating business in the shipping industry. Following our formation, our officers and directors were the holders of 9,026,924 shares of common stock representing all of our then issued and outstanding capital stock. On December 21, 2005, we consummated our initial public offering of 18,867,500 units, at a price of $10.00 per unit, each unit consisting of one share of Star Maritime common stock and one warrant to purchase one share of Star Maritime common stock. In addition, we completed a private placement of an aggregate of 1,132,500 units, each unit consisting of one share of common stock and one warrant, to Messrs. Tsirigakis and Syllantavos, our senior executive officers and Messrs. Pappas and Erhardt, two of our directors. As of October 9, 2007 the aggregate value of such securities was $24,042,975. The gross proceeds of the private placement of $11,325,500 were used to pay all fees and expenses of the initial public offering. As a result, the entire gross proceeds of the initial public offering of $188,675,000 were deposited in a trust account maintained by American Stock Transfer & Trust Company, as trustee, which we refer to as the Trust Account. If we do not complete the Redomiciliation Merger or another business combination transaction with a target business by December 21, 2007, we will be liquidated and we will distribute to all holders of our shares issued in the initial public offering in proportion to their respective equity interests, an aggregate sum equal to the amount in the Trust Account, including any interest (net of any taxes payable) not previously released to us, plus any remaining net assets. Our officers and directors have agreed to waive their respective rights to participate in any liquidation distribution should we fail to consummate a business combination transaction with respect to the aggregate of 9,026,924 shares of common stock issued to them prior to our initial public offering and with respect to the aggregate of 1,132,500 shares of common stock acquired by certain of our officers and directors in the private placement. In the event of our liquidation, we would not distribute funds from the Trust Account with respect to the Star Maritime warrants, which would expire worthless.

Star Bulk is a recently formed wholly-owned Marshall Islands subsidiary of Star Maritime and is headquartered in Athens, Greece. Pursuant to the Acquisition Agreements, following the Redomiciliation Merger, Star Bulk will acquire a fleet of eight drybulk carriers from certain subsidiaries of TMT. The eight drybulk carriers that Star Bulk has agreed to purchase constitute 12% of TMT's fleet of 63 vessels, including 22 newbuildings. Following the effective date of the Redomiciliation Merger, TMT and its affiliates are expected to own between 30.2% and 35.9% of the outstanding common stock of Star Bulk, depending on the number of shares of Star Maritime common stock redeemed for cash. See "Description of Star Maritime Securities—Common Stock." Star Bulk has applied to have its shares of common stock and warrants listed on the Nasdaq Global Market under the symbols "SBLK" and "SBLKW" respectively.

TMT is a global shipping company with its management headquarters located in Taiwan. TMT has approximately 50 years of experience in the shipping industry. TMT owns and/or operates or

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invests in vessels in several shipping sectors, including crude oil tankers, drybulk carriers and liquefied natural gas, or LNG, carriers.

Q:

When and where is the special meeting of Star Maritime stockholders?

A:

The special meeting of Star Maritime stockholders will take place at the offices of Seward & Kissel LLP, One Battery Park Plaza, 23rd Floor, New York, New York, on                        , 2007, at 10:00 a.m.

Q:

Who may vote at the special meeting?

A:

Only holders of record of shares of Star Maritime common stock as of the close of business on                        , 2007 may vote at the special meeting. As of October 9, 2007, there were 29,026,924 shares of Star Maritime common stock outstanding and entitled to vote.

Q:

What is the required vote to approve and authorize the Asset Acquisition?

A:

The Asset Acquisition must be approved by the holders of a majority of the issued and outstanding shares of common stock of Star Maritime. Adoption and approval of the Asset Acquisition is conditioned upon the adoption and approval of the Redomiciliation Merger. Star Bulk cannot complete the Asset Acquisition unless the Redomiciliation Merger is adopted and approved.

Q:

What is the required vote to approve and authorize the Redomiciliation Merger?

A:

The Delaware General Corporation Law requires that the Redomiciliation Merger must be approved by the holders of a majority of the issued and outstanding shares of common stock of Star Maritime.

In addition, the Redomiciliation Merger must be approved by the holders of at least a majority of the shares of common stock issued in the initial public offering and the private placement, or 10,000,001 shares. Star Maritime may not complete a business combination if the holders of 33% or more of the shares of common stock issued in the initial public offering and the private placement elect to exercise redemption rights in connection with the transaction. A vote in favor of the Redomiciliation Merger is, in effect, a vote in favor of Star Bulk's acquisition of the vessels from TMT.

Messrs. Tsirigakis and Syllantavos, our senior executive officers, and Messrs. Pappas and Erhardt, two of our directors, have agreed to vote an aggregate of 1,132,500 shares of Star Maritime common stock acquired by them in the private placement, which represents 3.9% of Star Maritime's outstanding common stock and 5.7% of the shares issued in the initial public offering and private placement, and any shares of Star Maritime common stock they may acquire in the future in favor of the Redomiciliation Merger and thereby waive redemption rights with respect to such shares. Star Maritime's officers and directors intend to consider the following factors in determining whether to make future purchases of Star Maritime common stock: (i) the trading price of our common stock, (ii) their aggregate investment in our securities, (iii) whether it appears that a substantial number of public stockholders are voting against the proposed Redomiciliation Merger and Asset Acquisition, and (iv) their post-transaction interest in Star Bulk and its business. Because any shares of our common stock acquired by our officers and directors in the aftermarket will be voted in favor of the Redomiciliation Merger and the Asset Acquisition, any such purchases could influence the result of the vote of our shareholders with respect to the Redomiciliation Merger and Asset Acquisition by making it more likely that the Redomiciliation Merger and Asset Acquisition would be approved. In addition, given the interest that our officers and directors have in the Redomiciliation Merger and Asset Acquisition being consummated, it is possible that our officers and directors will acquire securities from public stockholders who have elected to redeem their shares of our common stock in order to change their vote and insure that the Redomiciliation Merger and Asset Acquisition will be approved (which could result in the Redomiciliation Merger and Asset Acquisition being approved even if 33% or more of our public

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stockholders would have elected to exercise their redemption rights, or 51% of our public stockholders would have voted against the Redomiciliation Merger and Asset Acquisition, but for the purchases made by our officers and directors). Since the private placement on December 15, 2005, Star Maritime's officers and directors have not purchased additional shares of common stock and do not intend to purchase additional shares of common stock prior to the Redomiciliation Merger.

All of Star Maritime's officers and directors have agreed to vote an aggregate of 9,026,924 shares of Star Maritime common stock issued to them prior to our initial public offering in accordance with the vote of the holders of a majority of the shares issued in our initial public offering. Our officers and directors have agreed to waive their respective rights to participate in any liquidation distribution should we fail to consummate a business combination transaction with respect to the aggregate of 9,026,924 shares of common stock issued to them prior to our initial public offering and with respect to the aggregate of 1,132,500 shares of common stock acquired by certain of our officers and directors in the private placement.

Star Maritime will not be able to complete the Redomiciliation Merger unless (1) the holders of at least a majority of the issued and outstanding shares of Star Maritime entitled to vote at the special meeting vote in favor of the Redomiciliation Merger; (2) holders of at least 10,000,001 shares of common stock issued in the initial public offering and the private placement vote in favor of the Redomiciliation Merger; and (3) holders of less than 6,600,000 shares of common stock, such number representing 33.0% of the 20,000,000 shares of Star Maritime common stock issued in the initial public offering and private placement, vote against the Redomiciliation Merger and exercise their redemption rights to have their shares redeemed for cash. In order to exercise redemption rights, an eligible stockholder must vote against the Redomiciliation Merger and elect to exercise redemption rights on the enclosed proxy card. If a stockholder votes against the Redomiciliation Merger but fails to properly exercise redemption rights, such stockholder will not be entitled to have its shares redeemed for cash. Any request for redemption, once made, may be withdrawn at any time up to the date of the special meeting. The actual per share redemption price will be calculated two business days prior to the consummation of the Redomiciliation Merger. The redemption price would have been $10.39 per share, based on funds in the Trust Account as of June 30, 2007.

Q:

Has the board of directors of Star Maritime approved the Asset Acquisition?

A:

Yes. Star Maritime's board of directors has unanimously approved and recommended to the stockholders that they vote "FOR" the approval of the Asset Acquisition at the special meeting.

Q:

Has the board of directors of Star Maritime recommended approval of the Redomiciliation Merger?

A:

Yes. Star Maritime's board of directors has unanimously recommended to its stockholders that they vote " FOR " the approval and authorization of the Redomiciliation Merger at the special meeting. For various shipping regulatory and tax reasons, the Republic of the Marshall Islands is an attractive country of incorporation for international shipping companies. The merger of Star Maritime with and into Star Bulk with Star Bulk as the surviving corporation will enable Star Bulk, which will be an operating company, to benefit from such advantages. Please read "Background and Reasons for the Merger—Recommendations of the Board of Directors" for a discussion of the factors that the Star Maritime's board of directors considered in deciding to recommend the approval and authorization of the Redomiciliation Merger.

Q:

What will I receive in the Redomiciliation Merger?

A:

Pursuant to the Merger Agreement, each outstanding share of Star Maritime common stock will be converted into the right to receive one share of Star Bulk common stock and each outstanding

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warrant of Star Maritime will be assumed by Star Bulk and contain the same terms and restrictions except that each will be exercisable for common stock of Star Bulk.

Q:

When will Star Bulk take delivery of the vessels in the initial fleet?

A.

On the effective date of the Redomiciliation merger, at least one vessel will be delivered to Star Bulk. Star Bulk expects to take delivery of the remaining vessels in the initial fleet within 60 days following the effective date of the Redomiciliation Merger.

Q:

What are the tax consequences of the Redomiciliation Merger to me?

A:

In the opinion of Seward & Kissel LLP, counsel to Star Maritime, a holder of Star Maritime stock or warrants will not recognize any taxable gain or loss as a result of the Redomiciliation Merger.

Q:

What are the tax consequences of the Redomiciliation Merger to Star Maritime and Star Bulk?

A:

In the opinion of Seward & Kissel LLP, counsel to Star Maritime, upon completion of the Redomiciliation Merger and issuance of Star Bulk shares to TMT, the stockholders of Star Maritime will own less than 80% of Star Bulk. In the opinion of Seward & Kissel LLP, Star Bulk should not be subject to Section 7874(b) of the U.S. Internal Revenue Code of 1986, as amended, or the Code, after the Redomiciliation Merger if, as it believes should be the case, the Redomiciliation Merger and the subsequent issuance of Star Bulk shares to TMT are treated as part of a single Plan or Series of related transactions, and therefore should not be subject to U.S. federal income tax as a U.S. domestic corporation on its worldwide income after the Redomiciliation Merger. However, Star Maritime has not sought a ruling from the U.S. Internal Revenue Service, or the IRS, on this point. Therefore, there is no assurance that the IRS would not seek to assert that Star Bulk is subject to U.S. federal income tax on its worldwide income after the Redomiciliation Merger, although Star Maritime believes that such an assertion would not be successful.

Even if Section 7874(b) of the Code does not apply to a transaction, Section 7874(a) of the Code, or Section 7874(a), provides that where a corporation organized outside the United States acquires substantially all of the assets of a corporation organized in the United States, the corporation whose assets are being acquired will be subject to U.S. federal income tax on its "inversion gain" if stockholders of the U.S. corporation whose assets are being acquired own at least 60% of the non-U.S. acquiring corporation after the acquisition. "Inversion gain" includes any gain from the transfer of the properties by the corporation organized in the United States to the corporation organized outside the United States as well as certain licensing income. See "Tax Considerations."

Q:

What if I object to the Redomiciliation Merger?

A:

Under Star Maritime's Certificate of Incorporation, holders of shares of Star Maritime common stock have the right to redeem such shares for cash if such stockholder votes against the Redomiciliation Merger, elects to exercise redemption rights and the Redomiciliation Merger is approved and completed. In order to exercise redemption rights, an eligible stockholder must vote against the Redomiciliation Merger and elect to exercise redemption rights on the enclosed proxy card. If a stockholder votes against the Redomiciliation Merger but fails to properly exercise redemption rights, such stockholder will not be entitled to have its shares redeemed for cash. Stockholders exercising redemption rights will be entitled to receive, for each share of common stock redeemed, the pro rata portion of the Trust Account in which the proceeds of the Company's initial public offering are held, plus interest earned thereon (net of taxes). The redemption price would have been $10.39 per share, based on funds in the Trust Account as of June 30, 2007. If you exercise your redemption rights, then you will be exchanging your shares of Star Maritime's common stock for cash and will no longer own these shares. You will only be entitled to receive cash for these shares if you continue to hold these shares through the effective date of the Redomiciliation Merger and then tender your stock certificate to Star Maritime. If the

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Redomiciliation Merger is not completed, then these shares will not be redeemed for cash. A stockholder who exercises redemption rights will continue to own any warrants to acquire Star Maritime common stock owned by such stockholder as such warrants will remain outstanding and unaffected by the exercise of redemption rights. See "Description of Star Maritime Securities—Common Stock."

Q:

How can I vote?

A:

Please vote your shares of Star Maritime common stock as soon as possible after carefully reading and considering the information contained in this joint proxy statement/prospectus. You may vote your shares prior to the special meeting by signing and returning the enclosed proxy card. If you hold your shares in "street name" (which means, in other words, that you hold your shares through a bank, brokerage firm or nominee), you must vote in accordance with the instructions on the voting instruction card that your bank, brokerage firm or nominee provides to you.

Q:

If my shares are held in "street name" by my bank, brokerage firm or nominee, will they automatically vote my shares for me?

A:

No. Your bank, brokerage firm or nominee cannot vote your shares without instructions from you. You should instruct your bank, brokerage firm or nominee how to vote your shares, following the instructions contained in the voting instruction card that your bank, brokerage firm or nominee provides to you.

Q:

What if I abstain from voting or fail to instruct my bank, brokerage firm or nominee?

A:

Abstaining from voting or failing to instruct your bank, brokerage firm or nominee to vote your shares will have the same effect as a vote "against" the Redomiciliation Merger.

Q:

Can I change my vote after I have mailed my proxy card?

A:

Yes. You may change your vote at any time before your proxy is voted at the special meeting. You may revoke your proxy by executing and returning a proxy card dated later than the previous one, by attending the special meeting in person and casting your vote by ballot or by submitting a written revocation stating that you would like to revoke your proxy. If you hold your shares through a bank, brokerage firm or nominee, you should follow the instructions of your bank, brokerage firm or nominee regarding the revocation of proxies. You should send any notice of revocation or your completed new proxy card, as the case may be, to:

Star Maritime Acquisition Corp.
103 Foulk Road
Wilmington, Delaware 19803
Attention: Corporate Secretary

Q:

Should I send in my stock certificates now?

A:

No. After we complete the Redomiciliation Merger, you will receive written instructions for returning your stock certificates. These instructions will tell you how and where to send in your stock certificates in order to receive the Merger Consideration. Star Maritime shareholders who intend to have their shares redeemed, by electing to have those shares redeemed for cash on the proxy card at the same time they vote against the Redomiciliation Merger, should not send their certificate now, but should do so only after the effective date of the Redomiciliation Merger.

Q:

When is the Redomiciliation Merger expected to occur?

A:

Assuming the requisite the stockholder vote, we expect that the Redomiciliation Merger will occur during the fourth quarter of 2007. Our Certificate of Incorporation provides that if we have entered into definitive agreements to effect a business combination prior to June 21, 2007, we must consummate such business combination by December 21, 2007. Our agreements with TMT qualify as definitive agreements for these purposes.

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Q:

May I seek statutory appraisal rights with respect to my shares?

A:

Under applicable Delaware law, you do not have appraisal rights with respect to your shares.

Q:

What happens if the Redomiciliation Merger is not consummated?

A:

The acquisition of the eight drybulk carriers from TMT is contingent upon the approval and consummation of the Redomiciliation Merger. If Star Maritime does not consummate the Redomiciliation Merger or another transaction with a target business by December 21, 2007, then pursuant to Article SIX of its Certificate of Incorporation, Star Maritime's officers must take all actions necessary in accordance with the Delaware General Corporation Law to dissolve and liquidate Star Maritime within 60 days of that date. Following dissolution, Star Maritime would no longer exist as a corporation. In any liquidation, the funds held in the Trust Account, plus any interest earned thereon (net of taxes), together with any remaining out-of-trust net assets will be distributed pro-rata to holders of shares of Star Maritime common stock who acquired such shares of common stock in Star Maritime's initial public offering or in the aftermarket. The estimated consideration that each share of Star Maritime common stock would be paid at liquidation would be $10.39 per common share, based on amounts on deposit in the Trust Account as of June 30, 2007. The closing price of Star Maritime's common stock on the American Stock Exchange ("AMEX") on October 9, 2007 was $14.94 per share. Holders of shares issued prior to our initial public offering including holders of shares purchased in the private placement have waived any right to any liquidation distribution with respect to such shares. Liquidation and dissolution of Star Maritime would be effected pursuant to Delaware law, which would cause a delay in the distribution of proceeds. The proceeds distributed from the Trust Account may be reduced if a third party successfully asserts a claim against Star Maritime or one of its subsidiaries.

Q:

What happens post-Redomiciliation Merger to the funds deposited in the Trust Account?

A:

Following the approval of the Redomiciliation Merger by Star Maritime stockholders, funds in the Trust Account will be released to Star Maritime. Star Maritime stockholders exercising redemption rights will receive their pro rata portion of the Trust Account. The balance of the funds will be utilized to fund a portion of the cash portion of the aggregate purchase price for the eight dry bulk carriers in the initial fleet. As of June 30, 2007 the amount of funds from the Trust Account that will remain to be applied for the cash portion of the aggregate purchase price will be $196,084,213 if no shareholders redeem and $127,510,223 if the maximum 32.99% of shareholders redeem assuming a redemption price of $10.39.

Q:

What other important considerations are there?

A:

You should also be aware that in pursuing the Redomiciliation Merger, Star Maritime has incurred substantial expenses. Star Maritime currently has limited available funds outside the Trust Account and will, therefore, not be required to borrow funds or make arrangements with vendors and service providers in reliance on the expectation that such expenses will be paid by Star Bulk following consummation of the Redomiciliation Merger. Star Bulk intends to drawdown amounts under its credit facility sufficient to fund the balance of the cash portion of the aggregate purchase price of the vessels in the initial fleet to the extent that funds in the Trust Account are used to pay redeeming stockholders. In connection with the acquisition of the eight drybulk carriers, Star Bulk expects to borrow approximately $40.0 million if no shareholders redeem and approximately an additional $70.0 million if 32.99% of the shareholders redeem up to a maximum of $120.0 million. If for any reason the Redomiciliation Merger is not consummated, Star Maritime's creditors may seek to satisfy their claims from funds in the Trust Account. This could result in further depletion of the Trust Account, which would reduce a stockholder's pro rata portion of the Trust Account upon liquidation. As of the date of this joint proxy statement/prospectus, there are no creditor claims against Star Maritime or Star Bulk.

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Q:

Who will manage Star Bulk?

A:

Messrs. Tsirigakis and Syllantavos, who currently serve as the Chief Executive Officer and director and Chief Financial Officer and director of Star Maritime, respectively, will serve in these roles at Star Bulk following the Redomiciliation Merger. In addition, Messrs. Pappas, Erhardt and Søfteland, who currently serve as directors of Star Maritime, as well as Messrs. Nobu Su and Peter Espig, each of whom are nominees of TMT, will serve as directors of Star Bulk.

Q:

What is the anticipated dividend policy of Star Bulk?

A:

Star Bulk currently intends to pay quarterly dividends to the holders of its common shares in February, May, August and November, in amounts that will allow it to retain a portion of its cash flows to fund vessel or fleet acquisitions, and for debt repayment and other corporate purposes, as determined by its management and board of directors. Star Bulk intends to pay a dividend of $0.325 per share for the first full operating quarter following the Redomiciliation Merger. Star Bulk intends to pay a partial dividend in February 2008 which it estimates will be in an amount of $0.325 per common share pro rated for the number of ownership days during the fourth quarter of 2007. The payment of dividends is not guaranteed or assured and may be discontinued at the sole discretion of Star Bulk's board of directors and may not be paid in the anticipated amounts and frequency set forth in this joint proxy statement/prospectus. Star Bulk's board of directors will continually review its dividend policy and make adjustments that it believes appropriate. See "Dividend Policy of Star Bulk."

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SUMMARY

         This summary highlights selected information from this joint proxy statement/prospectus but may not contain all of the information that may be important to you. Accordingly, we encourage you to read carefully this entire joint proxy statement/prospectus, including eight Memoranda of Agreement attached as Appendix A through Appendix H, the Supplemental Agreement attached as Appendix I, the Master Agreement attached as Appendix J and the Agreement and Plan of Merger attached as Appendix K. Please read these documents carefully as they are the legal documents that govern the Redomiciliation Merger and your rights in the Redomiciliation Merger. We have included page references in parentheses to direct you to a more detailed description of the items presented in this summary. Unless the context otherwise requires, references to "we," "us" or "our" refers to Star Maritime.

The Parties to the Redomiciliation Merger (page 66)

Star Maritime Acquisition Corp.
103 Foulk Road
Wilmington, Delaware 19803
Telephone: (302) 656-1950

        Star Maritime is a blank check company, also known as a Business Combination Company™, or BCC™, organized under the laws of the State of Delaware on May 13, 2005. "Business Combination Company™" and "BCC™" are service marks of Maxim Group LLC. Star Maritime was formed to acquire, through a merger, capital stock exchange, asset acquisition or other similar business combination, one or more target businesses in the shipping industry. On December 15, 2005, Star Maritime consummated a private placement whereby certain of Star Maritime's officers and directors purchased an aggregate of 1,132,500 units at a purchase price of $10.00 per unit. On December 21, 2005, Star Maritime completed an initial public offering of 18,867,500 units at a purchase price of $10.00 per unit. Each unit consisted of one share of Star Maritime's common stock and one warrant. Each warrant entitles the holder to purchase one share of Star Maritime's common stock at an exercise price of $8.00 per share. Star Maritime's common stock and warrants currently trade on the American Stock Exchange under the symbols SEA and SEA.WS, respectively. Other than activities incident to its initial public offering and the pursuit of a business combination, Star Maritime has not engaged in any operations to date. If Star Maritime does not consummate the Redomiciliation Merger or another a business combination by December 21, 2007, then, pursuant to Article SIXTH of its Certificate of Incorporation, Star Maritime's officers must take all actions necessary in accordance with the Delaware General Corporation Law to dissolve and liquidate Star Maritime within 60 days of that date.

Star Bulk Carriers Corp.
40 Ag. Konstantinou Avenue
Aethrion Center, Suite B34
Maroussi 15124
Athens, Greece
Telephone: 011-30-210-638-7399

        Star Bulk is a wholly-owned Marshall Islands subsidiary of Star Maritime incorporated on December 13, 2006 with no history of operations, and is headquartered in Athens, Greece. Pursuant to the Acquisition Agreements, following the Redomiciliation Merger, Star Bulk will acquire a fleet of eight drybulk carriers from certain subsidiaries of TMT. Following the effective date of the Redomiciliation Merger, TMT and its affiliates are expected to own between 30.2% and 35.9% of the outstanding common stock of Star Bulk, depending on the number of shares redeemed for cash. See "Description of Star Maritime Securities—Common Stock."

        Mr. Akis Tsirigakis, the Chairman, Chief Executive Officer and President of Star Maritime, will serve as the Chief Executive Officer and President of Star Bulk. Mr. George Syllantavos, the Chief

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Financial Officer of Star Maritime will serve as the Chief Financial Officer of Star Bulk. The board of directors of Star Bulk will be comprised of seven directors. Each of the five current directors of Star Maritime will serve as directors of Star Bulk. In addition, Mr. Nobu Su and Mr. Peter Espig, each nominees of TMT, will serve as directors of Star Bulk. Mr. Petros Pappas and Mr. Nobu Su will each serve as non-executive Co-Chairman.

        Star Bulk has applied to have its shares of common stock and warrants listed on the Nasdaq Global Market under the symbols "SBLK" and "SBLKW" respectively.

The Seller of the Vessels in the Initial Fleet (page 60)

TMT Co., Ltd.
12 Floor 167 FU HSIN NORTH ROAD
Taipei 105
Taiwan, Republic of China
Attention: Corporate Secretary
011 886 2 221750229

        Star Bulk has entered into definitive agreements to acquire the eight drybulk carriers from subsidiaries of TMT. TMT is a global shipping company with its management headquarters located in Taiwan. TMT has approximately 50 years of experience in the shipping industry. TMT owns through companies registered in Panama and/or operates or invests in vessels in several shipping sectors, including crude oil tankers, drybulk carriers and liquified natural gas, or LNG, carriers.

The Redomiciliation Merger (page 66)

        Subject to the terms and conditions of the Merger Agreement, Star Maritime will merge with and into Star Bulk, a corporation organized under the laws of the Republic of the Marshall Islands, the separate corporate existence of Star Maritime will cease and Star Bulk will be the surviving corporation.

        Star Bulk has entered into definitive agreements to acquire a fleet of eight drybulk carriers with a combined cargo-carrying capacity of approximately 691,000 dwt. from certain subsidiaries of TMT. We refer to these eight drybulk carriers as the initial fleet. The aggregate purchase price for the initial fleet is $345,237,520, consisting of $224,500,000 in cash and 12,537,645 shares of common stock of Star Bulk to be issued at the time of Redomiciliation Merger and an additional 1,606,962 shares of common stock of Star Bulk to be issued in two installments. Such shares of common stock will be issued concurrently with the Redomiciliation Merger to TMT, as agent for its vessel-owning subsidiaries. Star Maritime has also entered into related agreements with TMT in connection with the acquisition of the vessels. Under the Master Agreement, Star Maritime, in connection with Star Bulk's acquisition of the vessels from TMT, undertook to use commercially reasonable efforts to file a registration/proxy statement with the Securities and Exchange Commission, or SEC, to obtain shareholder approval for the Redomiciliation Merger and to comply, and cause Star Bulk to comply, with all applicable rules and regulations of the SEC, and to obtain on behalf of itself, Star Bulk and TMT all approvals, consents, exemptions, or authorizations from such governmental agencies or authorities as may be necessary in order to effect the merger and transactions contemplated by the Master Agreement, the Supplemental Agreement, and the MOAs. Star Maritime is also a party to the Supplemental Agreement. The purpose of the Supplemental Agreement, generally, is to provide for the timing of the delivery of, and payment of the consideration for, the vessels as provided for under the MOAs. If the Redomiciliation Merger is not approved by the requisite vote of the stockholders of Star Maritime, the MOAs and the Supplemental Agreement shall be deemed terminated, cancelled and of no further force and effect.

        In connection with the acquisition of the vessels in the initial fleet, Star Bulk has also agreed to issue to TMT or its nominated affiliates, additional shares of Star Bulk common stock, which we refer

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to as the Additional Stock. Specifically, Star Bulk will issue (i) 803,481 additional shares of Star Bulk's common stock, no more than 10 business days following Star Bulk's filing of its Annual Report on Form 20-F for the fiscal year ended December 31, 2007, and (ii) 803,481 additional shares of Star Bulk's common stock, no more than 10 business days following Star Bulk's filing of its Annual Report on Form 20-F for the fiscal year ended December 31, 2008.

        Following the effective date of the Redomiciliation Merger, TMT and its affiliates are expected to own between 30.2% and 35.9% of Star Bulk's outstanding common stock, depending on the number of shares redeemed for cash. After giving effect to the issuance of the Additional Stock, TMT and its affiliates are expected to own between 32.8% and 38.7% of the Star Bulk's outstanding common stock, depending on the number of shares redeemed for cash.

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        The following chart illustrates the share ownership of Star Maritime prior to the Redomiciliation Merger and of Star Bulk following the Redomiciliation Merger.

        Upon issuance of the Additional Stock of 1,606,962 shares to TMT the breakdown of share ownership Post-Merger, assuming no redemptions, will be:

        Total 43,171,530 shares, Public : 43.7% - 18,867,500 shares, TMT : 32.8% - 14,144,607 shares, Sponsors : 23.5% - 10,159,424 shares

Redemption Rights (page 47)

        As provided in Star Maritime's Certificate of Incorporation, holders of Star Maritime common stock have the right to redeem their shares for cash by voting against the Redomiciliation Merger and electing to have such shares redeemed for cash. The exercise of redemption rights must be made on the proxy card at the same time that the stockholder votes against the Redomiciliation Merger. With respect to each share of common stock for which stockholders have exercised redemption rights, Star Maritime will redeem each such share for a pro rata portion of the Trust Account in which the proceeds of Star Maritime's initial public offering are held, plus interest earned thereon. As of June 30, 2007 the amount of funds from the Trust Account that will remain to be applied for the cash portion of the aggregate purchase price will be $196,084,213 if no shareholders redeem and $127,510,223 if the maximum 32.99% of shareholders redeem assuming a redemption price of $10.39. The actual per share redemption price will be calculated within two business days of the consummation of the Redomiciliation Merger. If you exercise your redemption rights, then you will be exchanging your shares of Star Maritime common stock for cash and will no longer own these shares. You will only be entitled to receive cash for these shares if you continue to hold these shares through the effective date of the Redomiciliation Merger and then tender your stock certificate to Star Maritime. If the Redomiciliation Merger is not completed, then these shares will not be redeemed for cash. A stockholder who exercises redemption rights will continue to own any warrants to acquire Star Maritime common stock owned by such stockholder as such warrants will remain outstanding and unaffected by the exercise of redemption rights.

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        The approval of the Asset Acquisition is conditioned upon the approval of the Redomiciliation Merger. Star Bulk cannot complete the Asset Acquisition unless the Redomiciliation Merger is approved and completed. Star Maritime cannot complete the Redomiciliation Merger unless (1) the holders of at least a majority of the issued and outstanding shares of Star Maritime entitled to vote at the special meeting vote in favor of the Redomiciliation Merger; (2) holders of at least a majority of the shares of common stock issued in the initial public offering and the private placement vote in favor of the Redomiciliation Merger; and (3) holders of less than 6,600,000 shares of common stock, such number representing 33.0% of the 20,000,000 shares of Star Maritime common stock issued in the initial public offering and private placement, vote against the Redomiciliation Merger and exercise their redemption rights to have their shares redeemed for cash. In order to exercise redemption rights, an eligible stockholder must vote against the Redomiciliation Merger and elect to exercise redemption rights on the enclosed proxy card. If a stockholder votes against the Redomiciliation Merger but fails to properly exercise redemption rights, such stockholder will not be entitled to have its shares redeemed for cash. Any request for redemption, once made, may be withdrawn at any time up to the date of the special meeting.

Merger Consideration (page 66)

        Pursuant to the Merger Agreement, each outstanding share of Star Maritime common stock will be converted into the right to receive one share of Star Bulk common stock and each outstanding warrant of Star Maritime will be assumed by Star Bulk and will contain the same terms and restrictions except that each will be exercisable for common stock of Star Bulk.

Procedure for Receiving Merger Consideration (page 66)

        Promptly after the effective time of the Redomiciliation Merger, an exchange agent appointed by Star Bulk will mail a letter of transmittal and instructions to Star Maritime stockholders. The letter of transmittal and instructions will tell Star Maritime stockholders how to surrender their stock certificates in exchange for the Merger Consideration. Star Maritime stockholders should not return their stock certificates with the enclosed proxy card, and they should not forward their stock certificates to the exchange agent without a letter of transmittal.

The Star Maritime Special Meeting (page 45)

        The special meeting of Star Maritime stockholders will take place at the offices of Seward & Kissel LLP, One Battery Park Plaza, 23rd Floor, New York, New York on                        , 2007, at 10 a.m.

Quorum, Record Date and Voting (page 45)

        A quorum of Star Maritime's stockholders is necessary to hold a valid meeting. A quorum will be present at the Star Maritime special meeting if a majority of the issued and outstanding shares of Star Maritime's common stock entitled to vote at the meeting are present in person or by proxy. Abstentions and broker non-votes will count as present for the purpose of establishing a quorum. Only holders of record of shares of Star Maritime common stock as of the close of business on                        , 2007 may vote at the Star Maritime special meeting. As of October 9, 2007, there were 29,026,924 shares of Star Maritime common stock outstanding and entitled to vote. Holders of shares of Star Maritime common stock will have one vote for each share of Star Maritime common stock owned at the close of business on the record date. Star Maritime warrants do not have voting rights.

Proxies (page 46)

        Proxies may be solicited by mail, telephone or in person. Star Maritime may engage a proxy solicitor to assist it in the solicitation of proxies. If you grant a proxy, you may still vote your shares in person if you revoke your proxy before the special meeting or if you attend the special meeting and vote in person.

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Recommendations of the Boards of Directors and Reasons for the Redomiciliation Merger (page 54)

        In reaching its decision with respect to the Redomiciliation Merger, the board of directors of Star Maritime considered the various regulatory and tax advantages to operating an international shipping company domiciled in the Republic of the Marshall Islands as compared to a corporation domiciled in the United States. The board of directors has unanimously determined that it is advisable and in the best interests of Star Maritime's stockholders to merge with and into Star Bulk, a wholly-owned Marshall Islands subsidiary, with Star Bulk as the surviving corporation, which would acquire vessels and operate as an international shipping company. In reaching its decision with respect to the merger with and into Star Bulk, which has entered into definitive agreements to acquire the vessels in the initial fleet, the board of directors of Star Maritime reviewed various due diligence materials including the vessels' classification society records, records relating to the vessels' physical inspection and vessel valuations prepared by independent purchase and sale brokers recognized in the international shipping industry, as well as advice provided by its financial advisors to Star Maritime's management. The board of directors of Star Maritime has unanimously determined that the Redomiciliation Merger is advisable and in the best interests of Star Maritime's stockholders and that the aggregate purchase price of the initial fleet to be paid by Star Bulk is reasonable. Accordingly, the Star Maritime board of directors unanimously recommends that Star Maritime stockholders vote " FOR " the approval and authorization of the Redomiciliation Merger at the Star Maritime special meeting.

Interests of Certain Persons in the Redomiciliation Merger (page 57)

        When you consider the recommendation of Star Maritime's board of directors that you vote in favor of approval of the Redomiciliation Merger, you should keep in mind that certain of Star Maritime's officers and directors have interests in the Redomiciliation Merger that are different from, or in addition to, your interest as a stockholder. These interests currently known to us are:

•

Star Maritime's officers and directors paid $25,000 in cash for a total of 9,026,924 shares of Star Maritime common stock prior to the initial public offering. These shares, without taking into account any discount that may be associated with certain restrictions on these shares, collectively have a market value of approximately $134,862,245 based on Star Maritime's share price of $14.94 as of October 9, 2007. Our initial stockholders have agreed to surrender up to an aggregate of 200,000 of their shares of common stock to us for cancellation upon consummation of a business combination in the event public stockholders exercise their right to have Star Maritime redeem their shares for cash. The number of shares that our initial stockholders will surrender will be determined by calculating the dollar amount of the Trust Account (exclusive of interest) paid to redeeming stockholders above $9.43 per share (which amount consists of $9.23 per share attributable to such stockholders and $0.20 per share attributable to the underwriters' deferred discount) and dividing it by $10.00 (the value attributed to the shares for purposes of this calculation). Accordingly, for each 1,000 shares redeemed up to 3,508,772 shares, our initial stockholders will surrender 57 shares for cancellation. None of the 9,026,924 shares issued prior to the initial public offering to these individuals may be released from escrow until December 15, 2008 during which time the value of the shares may increase or decrease; however, since such shares were acquired for $0.003 per share, the holders are likely to benefit from the Redomiciliation Merger notwithstanding any decrease in the market price of the shares. Further, if the Redomiciliation Merger is not approved and Star Maritime fails to consummate an alternative transaction within the requisite period and we are therefore required to liquidate, such shares do not carry the right to receive any distributions upon liquidation.



•

Messrs. Tsirigakis and Syllantavos, our senior executive officers and Messrs. Pappas and Erhardt, two of our directors, purchased an aggregate of 1,132,500 units in the private placement at a purchase price of $10.00 per unit (comprised of one share of common stock and one warrant to purchase a share of common stock of Star Maritime) or a total of $11,325,500, and as of October 9, 2007, the aggregate market value of such securities was $24,042,975. Star Maritime's officers and directors agreed to vote their common shares included in the units in favor of the

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Redomiciliation Merger and thereby waive redemption rights with respect to those shares. If the Redomiciliation Merger is not approved and Star Maritime fails to consummate an alternative transaction within the requisite period and Star Maritime is therefore required to liquidate, those shares do not carry the right to receive distributions upon liquidation. No officers or directors of Star Maritime or Star Bulk have purchased any securities of Star Maritime in the after market with the exception of 50,000 warrants purchased by Messr. Syllantavos on July 19, 2007 at a purchase price of $4.93 per warrant.

•

After the completion of the Redomiciliation Merger, Mr. Tsirigakis will serve as Star Bulk's Chief Executive Officer and President and Mr. Syllantavos will serve as Star Bulk's Chief Financial Officer. Star Bulk Management Inc., or Star Bulk Management, has entered into employment agreements with Messrs. Tsirigakis and Syllantavos. See "Information Concerning Star Bulk—Compensation of Directors and Senior Management." Star Bulk's board of directors will be comprised of seven directors. Each of the five current directors of Star Maritime will serve as directors of Star Bulk. In addition Mr. Su and Mr. Espig, each a nominee of TMT, will serve as directors. Mr. Pappas and Mr. Su will each serve as non-executive Co-Chairman of the board of Star Bulk. Such individuals will, following the Redomiciliation Merger, be compensated in such manner, and in such amounts, as Star Bulk's board of directors may determine to be appropriate. See "Information Concerning Star Bulk—Compensation of Directors and Senior Management."



•

Maxim Group LLC, the underwriters of our initial public offering, has an interest in the Redomiciliation Merger which consists of the $3,773,500 in contingent underwriting compensation and $226,500 of contingent placement fees held in the Trust Account as of March 31, 2007 that it will receive upon the consummation of a business combination as well as the $800,000 that it will receive in its financial advisory role with respect to the Redomiciliation Merger. In addition, Maxim has an interest in having as few shareholders as possible exercise their redemption rights because Maxim has agreed that it will forfeit $0.20 per share (up to a maximum of $1,286,730) plus interest thereon of its contingent underwriting compensation for each share redeemed by a shareholder in connection with a business combination transaction.



•

Mr. Nobu Su and Mr. Peter Espig, who are affiliates of TMT, will each join the board of directors of Star Bulk following the Redomiciliation Merger. Star Bulk has entered into one year time charters for two vessels in the initial fleet, the Star Gamma and the Star Iota, with TMT as the charterer. The estimated TMT payments and corresponding Star Bulk gross revenues from these charters will be $10,203,000 and $6,444,000 respectively for the two vessels for the duration of the time charter agreements.

Acquisition Financing (page 65)

        On May 10, 2007 Star Bulk entered into a commitment letter with Commerzbank AG that will, subject to the approval of the Redomiciliation Merger, provide Star Bulk with a credit facility of up to $120,000,000 with a minimum nine-year term and secured by the vessels that Star Bulk has agreed to acquire from TMT. Star Bulk intends to drawdown amounts under its credit facility sufficient to fund the balance of the cash portion of the aggregate purchase price of the vessels in the initial fleet to the extent that funds in the Trust Account are used to pay redeeming stockholders. Following the acquisition of the eight drybulk carriers, Star Bulk expects to have working capital of approximately $1.6 million. Any excess un-drawn funds under the credit facility will be used for additional vessel acquisitions and to provide working capital.

Conditions to the Redomiciliation Merger (page 68)

        The completion of the Redomiciliation Merger is subject to the satisfaction or, if permissible, waiver of a number of conditions, comprising of (i) Star Maritime obtaining the requisite approval of its shareholders; (ii) Star Maritime receiving an opinion of counsel that (x) the Redomiciliation Merger will be treated as a "reorganization" within the meaning of Section 368(a) of the Code; (y) each of Star

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Bulk and Star Maritime will be treated as a "party to a reorganization" within the meaning of Section 368(b) of the Code; and (z) neither Star Maritime nor the stockholders of Star Maritime will recognize any taxable gain or loss for U.S. federal income tax purposes upon the consummation of the Redomiciliation Merger; (iii) Star Maritime receiving certificates from officers of Star Bulk and from the Registrar of Corporations of the Republic of the Marshall Islands; and (iv) the absence of any Material Adverse Effect, as defined in the Merger Agreement, with respect to Star Bulk, the likelihood of which was not previously disclosed to Star Maritime by Star Bulk. Each condition to the completion of the Redomiciliation Merger may be waived other than obtaining the requisite vote of shareholders of Star Maritime. We expect to complete the Redomiciliation Merger during the third quarter of 2007, but we cannot be certain when or if the conditions will be satisfied or, if permissible, waived. Star Maritime believes that the only material condition to the completion of the Redomiciliation Merger is obtaining the requisite shareholder vote. Accordingly, Star Maritime does not anticipate resoliciting shareholder approval if any of the other conditions to the Redomiciliation Merger are waived. Star Maritime does not currently expect to waive any conditions of the Redomiciliation Merger.

        Star Maritime cannot complete the Redomiciliation Merger unless (1) the holders of at least a majority of the issued and outstanding shares of Star Maritime entitled to vote at the special meeting vote in favor of the Redomiciliation Merger; (2) holders of at least a majority of the shares of common stock issued in the initial public offering and the private placement vote in favor of the Redomiciliation Merger; and (3) holders of less than 6,600,000 shares of common stock, such number representing 33.0% of the 20,000,000 shares of Star Maritime common stock issued in the initial public offering and private placement, vote against the Redomiciliation Merger and exercise their redemption rights to have their shares redeemed for cash.

        The obligations of Star Bulk to purchase the vessels in the initial fleet and the obligations of TMT to sell the vessels in the initial fleet are subject to the approval of the Redomiciliation Merger and the Asset Acquisition by Star Maritime's stockholders in addition to customary closing conditions.

Termination of the Merger Agreement (page 68)

        The Merger Agreement may be terminated (i) at any time prior to the effective time of the Redomiciliation Merger by mutual consent in writing of Star Maritime and Star Bulk; or (ii) unilaterally upon written notice by either Star Maritime or Star Bulk, in the event of such other parties' material breach of any representation or warranty contained in the Merger Agreement.

Termination of the Master Agreement (page 62)

        The Master Agreement will terminate and be of no further force or effect in the event that the Redomiciliation Merger is not authorized and approved by the requisite vote of Star Maritimes' stockholders.

Liquidation if No Business Combination (page 70)

        You should also be aware that in pursuing the Redomiciliation Merger, Star Maritime has incurred substantial expenses. Star Maritime currently has limited available funds outside the Trust Account, and will therefore be required to borrow funds or make arrangements with vendors and service providers in reliance on the expectation that such expenses will be paid by Star Bulk following consummation of the Redomiciliation Merger. If for any reason the Redomiciliation Merger is not consummated, Star Maritime's creditors may also seek to satisfy their claims from funds in the Trust Account. This could result in depletion of the Trust Account, which would reduce a stockholder's pro rata portion of the Trust Account upon liquidation.

Material U.S. Federal Income Tax Consequences (page 58)

        Star Maritime has obtained the opinion of its counsel, Seward & Kissel LLP, that the Redomiciliation Merger will be treated as a nontaxable reorganization for U.S. federal income tax purposes. The opinion of Seward & Kissel LLP is subject to the limitations and qualifications set forth in the discussion of "Material

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U.S. Federal Income Tax Consequences." Because the Redomiciliation Merger will be treated as a nontaxable reorganization for U.S. federal income tax purposes, Star Bulk will not recognize gain or loss as a result of the Redomiciliation Merger. In addition, Star Maritime stockholders will not recognize gain or loss upon the exchange of their shares of Star Maritime common stock solely for shares of Star Bulk common stock pursuant to the Redomiciliation Merger. However, a Star Maritime stockholder who receives solely cash in exchange for his or her shares of Star Maritime common stock generally will recognize gain or loss for U.S. federal income tax purposes in an amount equal to the difference between his basis for U.S. federal income tax purposes in such shares and the cash received. The federal income tax consequences of the Redomiciliation Merger are complicated and may differ between individual stockholders. We strongly urge each Star Maritime stockholder to consult his or her own tax advisor regarding the federal income tax consequences of the Redomiciliation Merger in light of his or her own personal tax situation and also as to any state, local, foreign or other tax consequences arising out of the Redomiciliation Merger. Further, we do not give any opinion regarding the tax impact in the event that Star Maritime stockholders exercise redemption rights.

Accounting Treatment (page 59)

        The Redomiciliation Merger will be accounted for as a business combination between companies under common control with Star Bulk as the accounting acquirer. The assets and liabilities of Star Maritime acquired by Star Bulk will be recorded as of the acquisition date at their respective costs and added to those of Star Bulk. Following the effective date of the Redomiciliation Merger, Star Bulk will continue as the surviving company and the separate corporate existence of Star Maritime shall cease. Accordingly, the results of operations after completion of the acquisition will be those of Star Bulk.

Comparison of Star Maritime and Star Bulk Stockholder Rights (page 141)

        Star Maritime is incorporated under the laws of the State of Delaware. Star Bulk is incorporated under the laws of the Republic of the Marshall Islands. Upon consummation of the Redomiciliation Merger, the stockholders of Star Maritime will become shareholders of Star Bulk. Star Bulk's amended and restated articles of incorporation and by-laws differ from the organizational documents governing the rights of the former Star Maritime stockholders. In particular, Star Maritime's certificate of incorporation authorizes the issuance of up to 1,000,000 shares of blank check preferred stock by its board of directors. Star Bulk's articles of incorporation authorize the issuance of up to 25,000,000 shares of blank check preferred stock by the board of directors. Star Maritime's certificate of incorporation provides that a special meeting of stockholders may be called by a majority of the entire board of directors or the Chief Executive Officer, and shall be called by the Secretary at the request in writing of stockholders owning a majority in amount of the entire capital stock of the corporation issued and outstanding and entitled to vote. Star Bulk's organizational documents require that a special meeting of stockholders may only be called by the board of directors, jointly by the Co-Chairmen or the President. In addition, Star Bulk's articles of incorporation include a provision which limits Star Bulk from engaging in a business combination transaction with stockholders owning 20% or more of the outstanding voting stock of Star Bulk.

Regulatory Approvals (page 59)

        Star Maritime and Star Bulk do not expect that the Redomiciliation Merger will be subject to any state or federal regulatory requirements other than filings under applicable securities laws and the effectiveness of the registration statement of Star Bulk of which this joint proxy statement/prospectus is part, and the filing of certain merger documents with the Registrar of Corporations of the Republic of the Marshall Islands and with the Secretary of State of the State of Delaware. Star Maritime and Star Bulk intend to comply with all such requirements. We do not believe that, in connection with the completion of the Redomiciliation Merger, any consent, approval, authorization or permit of, or filing with or notification to, any merger control authority will be required in any jurisdiction.

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STAR MARITIME SUMMARY FINANCIAL INFORMATION

        Star Maritime Acquisition Corp. was incorporated in Delaware on May 13, 2005 to serve as a vehicle for the acquisition through a merger, capital stock exchange, asset acquisition, or other similar business combination with one or more businesses in the shipping industry. Star Maritime has not acquired an entity as of the date of this prospectus. Star Maritime has selected December 31 as its fiscal year end. Star Maritime is considered to be in the development stage and is subject to the risks associated with activities of development stage companies. The summary financial information set forth below should be read in conjunction with the audited financial statements of Star Maritime for the period from inception to December 31, 2006 and for the fiscal years ended December 31, 2005 and 2006 and related notes included elsewhere in this joint proxy statement/prospectus.

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STAR MARITIME ACQUISITION CORP.
UNAUDITED PRO FORMA COMBINED CONSOLIDATED BALANCE SHEET

        The following unaudited pro forma combined consolidated balance sheet presents the financial position of Star Maritime as of June 30, 2007, assuming the acquisition of the vessels had been completed as of June 30, 2007. The historical financial information has been adjusted to give effect to pro forma events that are directly attributable to the Redomiciliation Merger, factually supportable, and expected to have a continuing impact on the combined results.

        We are providing the following information to aid you in your analysis of the financial aspects of the Redomiciliation Merger. We derived this information from the unaudited balance sheet of Star Maritime as of June 30, 2007. This information should be read together with the Star Maritime audited financial statements and related notes and "Management's Discussion and Analysis of Financial Condition and Results of Operations" for Star Maritime and other financial information included elsewhere in this joint proxy statement/prospectus.

        The unaudited pro forma combined information is for illustrative purposes only. You should not rely on the unaudited pro forma combined balance sheet as being indicative of the historical financial position that would have been achieved had the Redomiciliation Merger been consummated as of this date.

See Notes to Unaudited Pro Forma Combined Consolidated Balance Sheet

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