SBLK Star Bulk Carriers Corporation

Filed Pursuant to Rule 424(b)(5)
Registration Number 333-197886

SUBJECT TO COMPLETION, DATED JANUARY 8, 2015

PRELIMINARY PROSPECTUS SUPPLEMENT
(To Prospectus dated September 5, 2014)

$200 million of Common Shares

We are offering     common shares to be sold in this offering. Our common shares are listed on the NASDAQ Global Select Market under the symbol “SBLK.” On January 7, 2015, the last reported sales price of our common shares on NASDAQ Global Select Market was $6.07.

We are offering $200 million of our common shares in this offering. As part of this offering, the “Significant Shareholders” described in “Prospectus Summary—The Offering” (the “Significant Shareholders”) have indicated that they intend to purchase approximately $149 million of our common shares at the public offering price per common share listed in the table below. We are offering the remaining approximately $51 million of the $200 million of our common shares to the public at the public offering price listed in the table below.

Investing in our common shares involves a high degree of risk. See the section entitled “Risk Factors” beginning on page S-22 of this prospectus supplement and the section entitled “Risk Factors” of the accompanying prospectus and in our Annual Report on Form 20-F for the fiscal year ended December 31, 2013, filed with the Securities and Exchange Commission on March 21, 2014 and incorporated by reference herein, to read about the risks you should consider before purchasing our common shares.

Neither the Securities and Exchange Commission nor any state securities commission has approved or disapproved of these securities or determined if this prospectus supplement or the accompanying prospectus is truthful or complete. Any representation to the contrary is a criminal offense.

We have granted the underwriters an option to purchase up to an additional        shares within 30 days after the date of this prospectus at the public offering price, less underwriting discounts and commissions. The Significant Shareholders will not participate in such option, if any.

The underwriters expect to deliver the shares to purchasers on or about January   , 2015 through the book−entry facilities of The Depository Trust Company.

The date of this prospectus is             , 2015

TABLE OF CONTENTS

Prospectus Supplement

Prospectus

ABOUT THIS PROSPECTUS SUPPLEMENT

This document is in two parts. The first part is this prospectus supplement, which contains specific information about the terms on which we are offering and selling the common shares. The second part is the accompanying prospectus dated September 5, 2014, which contains and incorporates by reference important business and financial information about us and other information about the offering. If the information set forth in this prospectus supplement differs in any way from the information set forth in the accompanying prospectus or the information contained in any document incorporated by reference herein or therein, the information contained in the most recently dated document shall control. All references in this prospectus supplement to this “prospectus” refer to this prospectus supplement together with the accompanying prospectus.

As permitted under the rules of the Securities and Exchange Commission, or the Commission, this prospectus incorporates important business information about us that is contained in documents that we have previously filed with the Commission but that are not included in or delivered with this prospectus. You may obtain copies of these documents, without charge, from the website maintained by the Commission at www.sec.gov, as well as other sources. You may also obtain copies of the incorporated documents, without charge, upon written or oral request to Star Bulk Carriers Corp., c/o Star Bulk Management Inc., 40 Agiou Konstantinou Str., Maroussi, 15124, Athens, Greece. See “Where You Can Find Additional Information.”

We do not authorize any person to provide information other than that provided in this prospectus and the documents incorporated by reference. We are not making an offer to sell the common shares in any state or other jurisdiction where the offer or sale is not permitted. You should assume that the information contained in this prospectus and the documents incorporated by reference is accurate only as of their respective dates, and you should not consider any information in this prospectus or in the documents incorporated by reference herein to be investment, legal or tax advice. We encourage you to consult your own counsel, accountant and other advisors for legal, tax, business, financial and related advice regarding an investment in our securities.

Unless otherwise indicated or unless the context requires otherwise, all references in this prospectus supplement to “Star Bulk,” the “Company,” “we,” “us,” “our,” or similar references, mean Star Bulk Carriers Corp. and, where applicable, its consolidated subsidiaries. In addition, we use the term deadweight, or dwt, in describing the size of vessels. Dwt expressed in metric tons, each of which is equivalent to 1,000 kilograms, refers to the maximum weight of cargo and supplies that a vessel can carry.

INFORMATION INCORPORATED BY REFERENCE

The Commission allows us to “incorporate by reference” information that we file with it. This means that we can disclose important information to you by referring you to those filed documents. The information incorporated by reference is considered to be a part of this prospectus, and information that we file later with the Commission prior to the termination of this offering will also be considered to be part of this prospectus and will automatically update and supersede previously filed information, including information contained in this document.

We incorporate by reference the documents listed below and any future filings made with the Commission under Section 13(a), 13(c), 14 or 15(d) of the Securities Exchange Act of 1934, as amended (the “Exchange Act”):

We are also incorporating by reference all subsequent Annual Reports on Form 20-F that we file with the Commission and certain reports on Form 6-K that we furnish to the Commission after the date of this prospectus that state that they are incorporated by reference into this prospectus until this offering is terminated. In all cases, you should rely on the later information over different information included in this prospectus. The list of documents incorporated above by reference supersedes the list of documents incorporated by reference by the accompanying prospectus dated September 5, 2014.

We are responsible for the information contained or incorporated by reference in this prospectus. We have not, and the underwriters have not, authorized any other person to provide you with different information, and we take no responsibility for different or inconsistent information that others may give you. We are not, and the underwriters are not, making an offer to sell these securities in any jurisdiction where the offer or sale is not permitted. You should assume that the information appearing in this prospectus as well as the information we previously filed with the Commission and incorporated by reference, is accurate as of the dates on the front cover of those documents only. Our business, financial condition and results of operations and prospects may have changed since those dates.

You may request a free copy of the above mentioned filings or any subsequent filing we incorporated by reference to this prospectus by writing or telephoning us at the following address:

Star Bulk Carriers Corp.
c/o Star Bulk Management Inc.
40 Agiou Konstantinou Str.
Maroussi 15124, Athens, Greece
011-30-210-617-8400 (telephone number)

WHERE YOU CAN FIND ADDITIONAL INFORMATION

As required by the Securities Act, we filed a registration statement relating to the securities offered by this prospectus with the Commission. This prospectus supplement is a part of that registration statement, which includes additional information.

We file annual and special reports with the Commission. You may read and copy any document that we file and obtain copies at prescribed rates from the Commission’s Public Reference Room at 100 F Street, N.E., Washington, D.C. 20549. You may obtain information on the operation of the Public Reference Room by calling 1 (800) SEC-0330. The Commission maintains a website (http://www.sec.gov) that contains reports, proxy and information statements and other information regarding issuers that file electronically with the Commission. Our filings are also available on our website at http://www.starbulk.com. The information on our website, however, is not, and should not be deemed to be, a part of this prospectus.

This prospectus supplement is part of the registration statement and does not contain all of the information in the registration statement. The full registration statement may be obtained from the Commission or us, as indicated below. Documents establishing the terms of the offered securities are filed as exhibits to the registration statement. Statements in this prospectus supplement about these documents are summaries and each statement is qualified in all respects by reference to the document to which it refers. You should refer to the actual documents for a more complete description of the relevant matters. You may inspect a copy of the registration statement at the Commission’s Public Reference Room in Washington, D.C., as well as through the Commission’s website.

CAUTIONARY STATEMENTS REGARDING FORWARD LOOKING STATEMENTS

This prospectus includes “forward-looking statements,” within the meaning of Section 27A of the Securities Act of 1933, as amended (the “Securities Act”), and Section 21E of the Exchange Act, with respect to our financial condition, results of operations and business and our expectations or beliefs concerning future events. Words such as, but not limited to, “believe,” “expect,” “anticipate,” “estimate,” “intend,” “plan,” “targets,” “projects,” “likely,” “would,” “could” and similar expressions or phrases may identify forward-looking statements.

All forward-looking statements involve risks and uncertainties. The occurrence of the events described, and the achievement of the expected results, depend on many events, some or all of which are not predictable or within our control. Actual results may differ materially from expected results.

In addition, important factors that, in our view, could cause actual results to differ materially from those discussed in the forward-looking statements include:

We have based these statements on assumptions and analyses formed by applying our experience and perception of historical trends, current conditions, expected future developments and other factors we believe are appropriate in the circumstances. All future written and verbal forward-looking statements attributable to us or any person acting on our behalf are expressly qualified in their entirety by the cautionary statements contained or referred to in this section. We undertake no obligation, and specifically decline any obligation, except as required by law, to publicly update or revise any forward-looking statements, whether as a result of new information, future events or otherwise. In light of these risks, uncertainties and assumptions, the forward-looking events discussed in this prospectus might not occur.

See the sections entitled “Risk Factors” of this prospectus supplement and the accompanying prospectus and “Item 3. Key Information—D. Risk Factors” in the 2013 20-F, which is incorporated herein by reference,

for a more complete discussion of these risks and uncertainties and for other risks and uncertainties. These factors and the other risk factors described in this prospectus are not necessarily all of the important factors that could cause actual results or developments to differ materially from those expressed in any of our forward-looking statements. Other unknown or unpredictable factors also could harm our results. Consequently, there can be no assurance that actual results or developments anticipated by us will be realized or, even if substantially realized, that they will have the expected consequences to, or effects on, us. Given these uncertainties, prospective investors are cautioned not to place undue reliance on such forward-looking statements.

PROSPECTUS SUMMARY

This summary highlights information contained or incorporated by reference in this prospectus and is qualified in its entirety by the more detailed information and financial statements included or incorporated by reference elsewhere in this prospectus. This summary may not contain all of the information that may be important to you. As an investor or prospective investor, you should carefully review this entire prospectus and the documents incorporated by reference herein, including the section of this prospectus entitled “Risk Factors” and the more detailed information that appears later in this prospectus before making an investment in our common shares. Where we refer to information on a “fully delivered basis,” we are referring to such information after giving effect to the delivery of all newbuilding vessels and all vessels being acquired from Excel Maritime Carriers Ltd. (“Excel”) in the Excel Transactions (as defined below).

OUR BUSINESS

We are an international shipping company with extensive operational experience that owns and operates a fleet of dry bulk carrier vessels. On a fully delivered basis, we will have a fleet of 102 vessels consisting primarily of Capesize as well as Kamsarmax, Ultramax and Supramax vessels with a carrying capacity between 38,900 dwt and 209,000 dwt. Our fleet included, as of December 31, 2014, 62 operating vessels, six vessels to be acquired from Excel during early 2015, and 35 vessels currently under construction at leading shipyards in Japan and China. Our vessels transport a broad range of major and minor bulk commodities, including ores, coal, grains and fertilizers, along worldwide shipping routes. Our highly experienced executive management team, with a combined 120 years of shipping industry experience, is led by Mr. Petros Pappas, who has more than 35 years of shipping industry experience and has managed more than 260 vessel acquisitions and dispositions.

On July 11, 2014, we closed transactions with entities affiliated with Oaktree Capital Management, L.P. and the family of Mr. Pappas, in which we acquired Oceanbulk Carriers LLC and Oceanbulk Shipping LLC (collectively “Oceanbulk”), two entities affiliated with the family of Mr. Pappas, as well as a loan that was converted into a 50% interest in a joint venture, Heron Ventures Limited (“Heron”) on November 5, 2014 (collectively, the “July 2014 Transactions”). As a result of the July 2014 Transactions, as of December 31, 2014 we added to our fleet 15 operating vessels (including two vessels, Peloreus and Leviathan, that were being built and were delivered on July 22, 2014 and September 19, 2014, respectively), with an average age of 4.8 years as of December 31, 2014 and an aggregate capacity of approximately 1.9 million dwt, two vessels distributed to us from Heron in December 2014 (the “Heron Vessels”) with an average age of 8.8 years as of December 31, 2014 and an aggregate capacity of 165,771 dwt, and contracts for the construction of 24 vessels, with an aggregate capacity of approximately 3.4 million dwt. In connection with the July 2014 Transactions, Mr. Pappas became our Chief Executive Officer, and our former Chief Executive Officer, Mr. Spyros Capralos, became our Non-Executive Chairman. See “The Transactions—The July 2014 Transactions.”

On August 19, 2014, we entered into definitive agreements with Excel, pursuant to which we are acquiring 34 operating dry bulk vessels, consisting of six Capesize vessels, 14 sistership Kamsarmax vessels, 12 Panamax vessels and two Handymax vessels (the “Excel Vessels”). The transfers of the Excel Vessels are being completed on a vessel-by-vessel basis, in general upon reaching port after their current voyages and cargoes are discharged. As of December 31, 2014, 28 of the Excel Vessels had been delivered to us, and we expect that the remaining six Excel Vessels will be delivered to us during early 2015. See “The Transactions—The Excel Transactions.” We refer to the foregoing transactions, together, as the “Excel Transactions”, and we refer to the July 2014 Transactions and the Excel Transactions, together, as the “Transactions.”

As of December 31, 2014, our operating fleet of 62 vessels, had an aggregate capacity of approximately 6.3 million dwt, which will be increased by approximately 0.5 million dwt with the addition of the six remaining Excel Vessels. We have also entered into or acquired contracts for the construction of 35 of the latest generation “Eco-type” vessels, which we define as vessels that are designed to be more fuel-efficient than standard vessels of similar size and age. As of December 31, 2014, the total payments for our 35 newbuilding vessels were expected to be $1,506.7 million, of which we had already paid $299.6 million. As of December 31, 2014, we had obtained commitments for $686.7 million of secured debt for 24 newbuilding vessels (which includes the debt drawn to finance the expected delivery of the Indomitable, see “Recent Developments—Payment for Indomitable”), we were in negotiations for an additional $292.5 million of secured debt for nine newbuilding vessels, and we were targeting an additional $65.0 million of secured debt for the remaining two newbuilding vessels. By the end of the second quarter of 2016, we expect our fleet to consist of 102 wholly owned vessels, with an average age of 7.8 years and an aggregate capacity of 11.8 million dwt. As of December 31, 2014, the

average age of our operating fleet was 9.4 years. On a fully delivered basis and based on publicly available information, we believe our fleet will make us the largest U.S. publicly traded dry bulk shipping company by deadweight tonnage.

Our fleet is well-positioned to take advantage of economies of scale in commercial, technical and procurement management, with all the Excel Vessels to be delivered by early 2015 and 28 of our 35 newbuilding vessels expected to be delivered during 2015. For our operating fleet, the Excel Vessels and our newbuildings, we have focused on vessels built at leading Japanese and Chinese shipyards, which, in our experience, are more reliable and less expensive to operate and are accordingly preferred by charterers. Currently, because of prevailing market conditions, we primarily employ our vessels in the spot market, under short term time charters or voyage charters. While employing the vessels under a voyage charter may require more management attention than under time charters, the vessel owner benefits from any fuel savings it can achieve because fuel is paid for by the vessel owner. On a fully-delivered basis, we will have a large, modern, fuel-efficient and high-quality fleet, which emphasizes the largest Eco-type Capesize and Newcastlemax vessels, built at leading shipyards and featuring the latest technology. As a result, we believe we will have an opportunity to capitalize on rising market demand during a period of reduced fleet growth, customer preferences for our ships and economies of scale, while enabling us to capture the benefits of fuel cost savings through spot time charters or voyage charters.

OUR FOUNDER AND HIS TRACK RECORD

Our founder and Chief Executive Officer, Mr. Pappas, has an established track record in the dry bulk industry, with more than 35 years of experience and more than 260 vessel acquisitions and dispositions. Entities under his management and control owned up to 30 vessels in 2001, most of which were acquired during the first quarter of 1997, the second quarter of 1998 and the second quarter of 2001, periods corresponding to low asset values and freight rates. Substantially all of these vessels were sold by the end of 2005, during a period of vessel values and levels of the Baltic Dry Index (“BDI”) (a daily average of charter rates for key dry bulk routes) that were record highs at the time.

As further described in “Management,” Mr. Pappas has extensive experience in operating and investing in shipping, including through his principal shipping operations and investment vehicle, Oceanbulk Maritime S.A. (“Oceanbulk Maritime”).

OUR FLEET

We have built a fleet through timely and selective acquisitions of secondhand and newbuilding vessels. Because of the industry reputation and extensive relationships of Mr. Pappas and the other members of our senior management, we have been able to contract for our newbuilding vessels with leading shipyards at prices that we believe reflect the recent bulk shipping downturn. We believe that owning a modern, well-maintained fleet reduces operating costs, improves the quality of service we deliver and provides us with a competitive advantage in securing favorable spot time charters and voyage charters with high-quality counterparties. Each of our newbuilding vessels will be equipped with a vessel remote monitoring system that will provide data to a central location in order to monitor fuel and lubricant consumption and efficiency on a real-time basis. We expect to retrofit all of our operating vessels and Excel Vessels with a similar monitoring system. While these monitoring systems are generally available in the shipping industry, we believe that they can be cost-effectively employed only by large-scale shipping operators, such as us.

Our fleet, which emphasizes large Capesize vessels, primarily transports minerals from the Americas and Australia to East Asia, particularly China, but also Japan, Korea, Taiwan, Indonesia and Malaysia. Our Supramax vessels carry minerals, grain products and steel between the Americas, Europe, Africa, Australia and Indonesia and from these areas to China, Korea, Japan, Taiwan, the Philippines and Malaysia.

Our newbuilding vessels are being built at leading Japanese and Chinese shipyards. The following tables summarize key information about our fully delivered fleet, as of December 31, 2014:

Operating Fleet

Acquired fleet to be delivered

Newbuilding Vessels

SIGNIFICANT FUEL SAVINGS OF OUR ECO-TYPE VESSELS

We believe that our investment in modern fuel efficient Eco-type newbuilding vessels will help us generate a superior time charter equivalent rate per day (“TCE rate”) compared to standard Baltic description vessels. All of our Eco-type newbuildings have significant technological improvements over the operating dry bulk vessels in their respective size categories, such as electronically controlled engines and optimized hull and propeller designs that have reduced water resistance and helped decrease fuel consumption.

While the shipping industry uses TCE rate as a key performance indicator, cargo owners chartering vessels on a voyage basis generally consider the cost per ton to move their cargo between ports and generally are indifferent to the resulting TCE rate, which depends on fuel costs, port and canal costs and speed. Two ships generating the same gross revenue per ton for the same voyage can therefore earn very different TCE rates based on different fuel consumption, speed and the number of tons of cargo each can carry.

When freight rates are relatively low (leading to low TCE rates), our Eco-type vessels enable us to generate higher TCE rates than non-Eco ships even when both are operated at low “Eco speeds,” which are the lowest speeds typically specified by the owners of vessels for normal operations. As freight rates rise, higher speeds are more profitable but our Eco-ships maintain a fuel cost advantage. The advantage of Eco-ships and lower speeds increases as fuel prices rise.

Assuming that the charter market remains at current levels, we intend to operate our vessels in the spot (or voyage) and short-term time charter market in order to benefit from any future increases in charter rates. If charter market levels rise, we may employ part of our fleet in the long-term time charter market, while we may be able to more advantageously employ our newbuilding fleet in the spot market in order to capture the benefit of available fuel cost savings.

OUR COMPETITIVE STRENGTHS

We believe that we possess a number of competitive strengths in our industry, including:

Track record of fleet growth with an extensive pipeline of attractive newbuilding vessels

Since 2007, assuming completion of the Excel Transactions, we will have successfully acquired 73 on the water modern dry bulk carrier vessels built between 1992 and 2014, with a total capacity of approximately 12.0 million dwt, including 22 Capesize, four Post-Panamax, 20 Kamsarmax, 13 Panamax, two Ultramax, ten Supramax and two Handymax vessels. During the same period we have successfully disposed of six older dry bulk carrier vessels, including four Capesize, one Panamax and one Handymax vessel.

As of December 31, 2014, our operating fleet of 62 modern dry bulk carrier vessels and the six Excel Vessels to be delivered to us during early 2015 were built at leading Japanese, Chinese and Korean shipyards between 1993 and 2014, all of which are serving existing customers. Our management team’s newbuilding philosophy has been to focus on building vessels exclusively at what we believe to be among the leading shipyards in Japan and China rather than simply purchasing available slots at any shipyard. Based on our experience, we believe that charterers will prefer newer, high-quality vessels and that such vessels will help to reduce operating and maintenance expenses and increase utilization rates. Mr. Pappas has leveraged his relationships with the shipyards to carefully plan our 35-vessel newbuilding program, including Capesize ships built at JMU, which we believe are very desirable because of their fuel efficiency and reliability. Our newbuilding program is designed to take advantage of economies of scale as quickly as practicable, adding a total capacity of approximately 5.0 million dwt, with 28 of the 35 vessels to be delivered in 2015. As of December 31, 2014, the average age of our operating fleet, together with the remaining Excel Vessels, was 9.9 years. When our newbuilding program is completed (which we expect in the third quarter of 2016), on a fully delivered basis, our fleet is expected to consist of 102 wholly owned vessels, with an average age of 7.8 years and an aggregate capacity of 11.8 million dwt. We believe that our operating fleet, the Excel Vessels and our expected newbuilding delivery schedule give us a competitive advantage.

Focus on fuel efficiency and improving vessel operations

All of our 35 newbuilding vessels are Eco-type vessels, and our Capesize ships being built at JMU in Japan have some of the lowest projected fuel consumption rates in the Capesize market. These fuel-efficient Eco-type vessels will enable us to take advantage of available fuel cost savings and operational efficiencies and give us the

opportunity to generate advantageous TCE rates, particularly in an environment in which fuel costs are high and charterhire rates are relatively low. In addition, each of our newbuilding vessels will be equipped with a sophisticated vessel remote monitoring system that will allow us to collect real-time information on the performance of critical on-board equipment, with a particular focus on fuel consumption and engine performance. Using this information, we will be able to be proactive in identifying potential problems and evaluating optimum operating parameters during various sea passage conditions. We will also be able to compare actual vessel performance to reported vessel performance and provide feedback to crews in real time, thereby reducing the likelihood of errors or omissions by our crews. Similar systems will be retrofitted to all of our operating vessels and most of the Excel Vessels. The vessel remote monitoring system is designed to enhance our ability to manage the operations of our vessels, thereby increasing operational efficiency and reducing maintenance costs and off-hire time. In addition, because 14 of the Excel Vessels and a number of our newbuilding vessels will be sister ships, we can take advantage of efficiencies in crewing, training and spare parts inventory management and can apply technical and operational knowledge of one ship to its sister ships. In addition to our newbuilding Eco-type vessels, 30 of our operating vessels are being equipped with sliding engine valves and alpha lubricators, making them semi-Eco vessels with increased fuel efficiency and decreased lubricant consumption. Most of the Excel Vessels either are equipped or are in the process of being equipped with similar features for increased fuel efficiency and decreased lubricant consumption.

Experienced management team with strong track record in the shipping industry

Our company’s leadership has considerable shipping industry expertise. Our founder and Chief Executive Officer, Mr. Pappas, has an established track record in the dry bulk industry, with more than 35 years of experience and more than 260 vessel acquisitions and dispositions. Mr. Pappas has extensive experience in operating and investing in shipping, including through his principal shipping operations and investment vehicle, Oceanbulk Maritime. Mr. Pappas also has extensive relationships in the shipping industry, and he has leveraged his deep relationships with shipbuilders to formulate our newbuilding program.

Mr. Hamish Norton, our President, is also the Head of Corporate Development and Chief Financial Officer of Oceanbulk Maritime with more than 22 years of experience in the shipping industry. Prior to joining Oceanbulk Maritime, from 2007 through 2012, Mr. Norton was a Managing Director and the Global Head of the Maritime Group at Jefferies LLC, and from 2003 to 2007, he was head of the shipping practice at Bear Stearns. Mr. Norton has advised in numerous capital markets and mergers and acquisitions transactions by shipping companies.

Mr. Christos Begleris, our Co-Chief Financial Officer, has served as Deputy Chief Financial Officer of Oceanbulk Maritime since 2013 and was the Chief Financial Officer of Oceanbulk from January 2014. He has been involved in the shipping industry since 2008 and has considerable banking and capital markets experience, having executed more than $9.0 billion of acquisitions and financings.

Mr. Simos Spyrou, our Co-Chief Financial Officer, has served as Chief Financial Officer of Star Bulk since September 2011. Mr. Spyrou has more than 15 years of experience in the Greek equity and derivative markets at the Hellenic Exchanges Group.

Mr. Nicos Rescos, our Chief Operating Officer, has served as the Chief Operating Officer of Oceanbulk Maritime since April 2010 and the Commercial Director and Chief Operating Officer of Oceanbulk since April 2000. He has been involved in the shipping industry in key commercial positions since 1993 and has strong expertise in the dry bulk, container and product tanker markets, having been responsible for more than 150 vessel acquisitions and dispositions.

Mr. Zenon Kleopas, our Executive Vice-President—Technical & Operations, joined us in July 2011 and has over 30 years of experience in the shipping industry. He was actively involved in the acquisition of our initial fleet in 2007 and 2008. He has extensive experience in ship operations and supervising ship management through his continuous employment in shipping companies in the United Kingdom and Greece since 1980.

Extensive relationships with customers, lenders, shipyards and other shipping industry participants

Through Mr. Pappas and our senior management team, we have strong global relationships with shipping companies, charterers, shipyards, brokers and commercial shipping lenders. Our senior management team has a long track record in the voyage chartering of dry bulk ships (including those that comprise our operating fleet),

which we expect will be of great benefit to us in increasing the profitability of our newbuilding fleet. The chartering team has had long experience in the business of arranging voyage and short-term time charters and can leverage its extensive industry relationships to arrange for favorable and profitable charters. We believe that these relationships with these counterparties and our strong sale and purchase track record and reputation as a creditworthy counterparty should provide us with access to attractive asset acquisitions, chartering and ship financing opportunities. Mr. Pappas has also leveraged his deep relationships with various shipyards to enable us to implement our newbuilding program and obtain attractive slots at those shipyards.

OUR BUSINESS STRATEGIES

Our primary objectives are to grow our business profitably and to continue to grow as a successful owner and operator of dry bulk vessels. The key elements of our strategy are:

Capitalize on expected increases in demand for dry bulk shipping

We have observed a recent downward volatility in dry bulk charterhire rates. Based on our analysis of industry dynamics, we believe that dry bulk charterhire rates will rise for the medium term, coinciding with our expected fleet expansion. While the charter market remains at current levels, we intend to operate our vessels in the spot and short-term time charter market in order to benefit from any future increases in charter rates.

Charter our vessels in an active and sophisticated manner

Our business strategy is centered on arranging voyage and spot time charters for our vessels, an approach that is tailored specifically to the fuel efficiency of our fleet, particularly our newbuilding vessels. While this process is more difficult and labor-intensive than placing our vessels on longer-term time charters, it can lead to greater profitability, particularly for vessels that have lower fuel consumption than typical vessels. We expect to apply the same strategy to employ the Excel Vessels as they are delivered to us, to the extent they are not subject to long-term time charters at delivery. When operating a vessel on a voyage charter, we (as owner of the vessel) will incur fuel costs, and therefore, we are in a position to benefit from fuel savings (particularly for our Eco-type vessels). If charter market levels rise, we may employ part of our fleet in the long-term time charter market, while we may be able to more advantageously employ our newbuilding fleet in the voyage charter market in order to capture the benefit of available fuel cost savings. For a long-term time charter, a rate based in part on the projected fuel consumption of our ship must be negotiated, and we may not be given full credit by the chartering party for the fuel efficiency of our vessels.

Expand our fleet through opportunistic acquisitions of high-quality vessels at attractive prices

As of December 31, 2014, we had contracts for 35 additional newbuilding vessels with an aggregate capacity of approximately 5.0 million dwt. We have also entered into the Excel Transactions, pursuant to which, we agreed to acquire 34 operating vessels with an aggregate capacity of approximately 3.2 million dwt (of which 28 vessels with a capacity of 2.6 million dwt had been delivered to us as of December 31, 2014, one of which, Star Kim, was sold in December 2014 and will be delivered to the new owners in January 2015). We intend to continue to opportunistically acquire high-quality vessels at attractive prices. When evaluating acquisitions, we will consider and analyze, among other things, our expectation of fundamental developments in the dry bulk shipping industry sector, the level of liquidity in the resale and charter market, the cash flow earned by the vessel in relation to its value, its condition and technical specifications with particular regard to fuel consumption, expected remaining useful life, the credit quality of the charterer and duration and terms of charter contracts for vessels acquired with charters attached, as well as the overall diversification of our fleet and customers. We believe that these circumstances combined with our management’s knowledge of the shipping industry may present an opportunity for us to grow our fleet at favorable prices.

Maintain a strong balance sheet through moderate use of leverage

We plan to finance our fleet, including future vessel acquisitions, with a mix of debt and equity, and we intend to maintain moderate levels of leverage over time (as described below), even though we may have the capacity to obtain additional financing. As of September 30, 2014, our debt to total capitalization ratio was approximately 36%. By maintaining moderate levels of leverage, we maintain greater flexibility than our more leveraged competitors to operate our vessels under shorter spot or period charters. Charterers have increasingly

favored financially solid vessel owners, and we believe that our balance sheet strength will enable us to access more favorable chartering opportunities, as well as give us a competitive advantage in pursuing vessel acquisitions from commercial banks and shipyards, which in our experience have recently displayed a preference for contracting with well-capitalized counterparties.

Oaktree

Oaktree is our largest shareholder. Oaktree Capital Management, L.P., together with its affiliates, is a leader among global investment managers specializing in alternative investments, with $93.2 billion in assets under management as of September 30, 2014. The firm emphasizes an opportunistic, value-oriented and risk-controlled approach to investments in distressed debt, corporate debt (including high yield debt and senior loans), control investing, convertible securities, real estate and listed equities. Headquartered in Los Angeles, the firm has over 800 employees and offices in 16 cities worldwide. See “—The Transactions—The July 2014 Transactions” for a discussion on the various limitations on the transfer and voting of our common shares by Oaktree.

Corporate and Other Information

We are a Marshall Islands corporation with principal executive offices at 40 Agiou Konstantinou Street, 15124, Athens Greece. Our telephone number at that address is 011-30-210-617-8400. We maintain a website on the Internet at http://www.starbulk.com. The information on our website is not incorporated by reference into this prospectus and does not constitute a part of this prospectus. We were incorporated in the Marshall Islands on December 13, 2006, as a wholly-owned subsidiary of Star Maritime Acquisition Corp., or Star Maritime, which was a special purpose acquisition corporation. We merged with Star Maritime on November 30, 2007 and commenced operations on December 3, 2007, which was the date we took delivery of our first vessel.

THE TRANSACTIONS

The July 2014 Transactions

In July 2014, we completed a transaction in which we acquired Oceanbulk Shipping LLC (“Oceanbulk Shipping”) and Oceanbulk Carriers LLC, (“Oceanbulk Carriers”, and, together with Oceanbulk Shipping, “Oceanbulk”) from Oaktree Dry Bulk Holdings LLC (including affiliated funds, “Oaktree”) and Millennia Holdings LLC (“Millennia Holdings”, and together with Oaktree, the “Sellers”), through the merger of our wholly-owned subsidiaries into Oceanbulk’s holding companies (the “Merger”). Oceanbulk owned and operated a fleet of 12 dry bulk carrier vessels and owned contracts for the construction of 25 newbuilding dry bulk vessels fuel-efficient Eco-type vessels (two of which, Peloreus and Leviathan, were delivered to us on July 22, 2014 and September 19, 2014, respectively) at shipyards in Japan and China. Millennia Holdings is an entity that is affiliated with the family of Mr. Petros Pappas, who became our Chief Executive Officer in connection with the Merger.

The agreement governing the Merger also provided for the acquisition by us (the “Heron Transaction”) of two Kamsarmax vessels (the “Heron Vessels”), from Heron Ventures Ltd. (“Heron”), a limited liability company incorporated in Malta. We issued 2,115,706 of our common shares into escrow as consideration for the Heron Vessels. The common shares are expected to be released from escrow to the Sellers under the Merger Agreement by early 2015, following the transfer of the Heron Vessels to us on December 5, 2014. In addition to the issued shares, in November 2014, we entered into a loan agreement with CiT Finance LLC for $25.3 million, to finance the cash consideration related to the acquisition of the Heron Vessels. For more information, see “Recent Developments—Heron Vessel Financing.”

In addition, concurrently with the Merger, we completed a transaction (the “Pappas Transaction”), in which we acquired all of the issued and outstanding shares of Dioriga Shipping Co. and Positive Shipping Company (collectively, the “Pappas Companies”), which were entities owned and controlled by affiliates of the family of Mr. Pappas. The Pappas Companies owned and operated a dry bulk carrier vessel (Tsu Ebisu) and had a contract for the construction of a newbuilding dry bulk carrier vessel, HN 5016 (tbn Indomitable), which was delivered to us on January 8, 2015.

We refer to the Merger, the Heron Transaction and the Pappas Transaction, together, as the “July 2014 Transactions.”

A total of 54,104,200 of our common shares were issued to the various selling parties in the July 2014 Transactions, of which 45,460,324 shares were issued to Oaktree, and 8,643,876 shares were issued to owners of the Pappas Companies and Millennia Holdings.

In connection with the July 2014 Transactions, we increased the number of directors constituting our Board of Directors to nine and, following the resignation of Ms. Milena Pappas as a director, appointed Mr. Rajath Shourie, Ms. Emily Stephens, Ms. Renée Kemp and Mr. Stelios Zavvos as additional directors.

In connection with the July 2014 Transactions, Mr. Petros Pappas became our Chief Executive Officer, Mr. Hamish Norton became our President, Mr. Christos Begleris became our Co-Chief Financial Officer, Mr. Nicos Rescos became our Chief Operating Officer and Ms. Sophia Damigou became our Co-General Counsel. Mr. Spyros Capralos resigned as our Chief Executive Officer but will remain with the Company as our Chairman, and Mr. Zenon Kleopas (our former Chief Operating Officer) will continue as our Executive Vice President—Technical Operations.

Oaktree Agreements. At the closing of the July 2014 Transactions, we and Oaktree entered into a shareholders agreement (the “Oaktree Shareholders Agreement”). Under the Oaktree Shareholders Agreement, Oaktree has the right to nominate four of our nine directors so long as it beneficially owns 40% or more of our outstanding voting securities. The number of directors able to be designated by Oaktree is reduced to three directors if Oaktree beneficially owns 25% or more but less than 40% of our outstanding voting securities, to two directors if Oaktree beneficially owns 15% or more but less than 25% and to one director if Oaktree beneficially owns 5% or more but less than 15%. Oaktree’s designation rights terminate if it beneficially owns less than 5% of our outstanding voting securities. Four individuals designated by Oaktree are currently our directors (Messrs. Pappas and Shourie and Mses. Stephens and Kemp).

Under the Oaktree Shareholders Agreement, with certain limited exceptions, Oaktree effectively cannot vote more than 33% of our outstanding common shares (subject to adjustment under certain circumstances).

Pursuant to the Oaktree Shareholders Agreement, so long as Oaktree and its affiliates beneficially own at least 10% of our outstanding voting securities, Oaktree and its affiliates have agreed not to directly or indirectly acquire beneficial ownership of any additional voting securities of ours or other equity-linked or other derivative securities with respect to our voting securities if such acquisition would result in Oaktree’s beneficial ownership exceeding 63.6%, subject to certain specified exceptions. In addition, pursuant to the Oaktree Shareholders Agreement, subject to various exclusions, so long as Oaktree and its affiliates beneficially own at least 10% of our voting securities, unless specifically invited in writing by our Board of Directors, they may not (i) enter into any tender or exchange offer or various types of merger, business combination, restructuring or extraordinary transactions, (ii) solicit proxies or consents in respect of such transactions, (iii) otherwise act to seek to control or influence our management, Board of Directors or other policies (except with respect to the nomination of Oaktree designees pursuant to the Oaktree Shareholders Agreement and other nominees proposed by the Nominating and Corporate Governance Committee) or (iv) enter into any negotiations, arrangements or understandings with any third party with respect to any of the above.

Pursuant to the Oaktree Shareholders Agreement, Oaktree also agreed to various limitations on the transfer of its common shares.

In addition, at the closing of the July 2014 Transactions, we entered into a registration rights agreement, which grants Oaktree (and certain other significant shareholders) customary demand, shelf and piggyback registration rights.

See Exhibit 99.3 to the Transaction 6-K for more information regarding the Oaktree Shareholders Agreement and the registration rights agreement.

Pappas Shareholders and Related Arrangements. At the closing of the July 2014 Transactions, the Pappas family and their affiliates (collectively, the “Pappas Shareholders”) entered into a shareholders agreement (the “Pappas Shareholders Agreement”) with us. Pursuant to the Pappas Shareholders Agreement, the various Pappas Shareholders agreed to various voting and standstill restrictions that are similar to those applicable to Oaktree and its affiliates under the Oaktree Shareholders Agreement, including a limitation on voting of 15% of our outstanding common shares (subject to adjustment under certain circumstances). The Pappas Shareholders also are parties to the registration rights agreement. See Exhibit 99.3 to the Transaction 6-K for more information regarding the Pappas Shareholders Agreement and the registration rights agreement.

While Mr. Petros Pappas expects that he will spend substantially all of such time as he devotes to the dry bulk shipping industry managing our company, Mr. Pappas is not required to work full-time on our affairs. We expect that the amount of time Mr. Pappas allocates to managing our company will vary from time to time depending on the needs of the business and the level of strategic activity at the time.

The Excel Transactions

In August 2014, we entered into definitive agreements relating to the Excel Transactions with Excel, pursuant to which we are acquiring the 34 Excel Vessels for an aggregate of 29,917,312 common shares (the “Excel Vessel Share Consideration”) and $288.4 million in cash. The Excel Vessels are being transferred to us in a series of closings, on a vessel-by-vessel basis, in general upon reaching port after their current voyages and cargoes are discharged. In the case of three Excel Vessels (Christine (tbr Star Martha), Sandra (tbr Star Pauline) and Lowlands Beilun (tbr Star Despoina)) which were transferred subject to existing charters, we received the outstanding equity interests of the vessel-owning subsidiaries that own those Excel Vessels (although all other assets and liabilities of such vessel-owning subsidiaries remained with Excel). As of December 31, 2014, 28 of the 34 Excel Vessels had been transferred to us, for aggregate consideration of 25,659,425 common shares and $248.9 million of cash. We expect to complete the remaining Excel Vessel closings in early 2015.

Entities affiliated with Oaktree (the “Oaktree Excel Investors”) and entities affiliated with Angelo, Gordon & Co. (“Angelo, Gordon”) are holders of 46.7% and 23.6%, respectively, of the outstanding equity of Excel. The Excel Transactions were approved by the disinterested members of our board of directors, based upon the recommendation of a transaction committee of disinterested directors, which considered the Excel Transactions on our behalf in coordination with our management team. The total consideration was determined based on the average of three vessel appraisals by independent vessel appraisers.

At the transfer of each Excel Vessel, we will pay the cash and share consideration for such Excel Vessel to Excel. We have been using cash on hand, borrowings under other debt facilities and borrowings under a $231.0 million secured bridge loan facility (the “Excel Vessel Bridge Facility”) extended to us by entities affiliated with Oaktree and entities affiliated with Angelo, Gordon to fund the cash consideration for the Excel Vessels. Excel uses the cash consideration to cause an amount of outstanding indebtedness under its senior secured credit agreement to be repaid, such that all liens and obligations with respect to the transferred Excel Vessel (or vessel-owning subsidiary) are released upon the transfer to us. We have been informed that Excel expects to distribute the Excel Vessel Share Consideration to its equityholders, including the Oaktree Excel Investors and Angelo, Gordon.

In connection with the foregoing transactions, we entered into an amendment to our existing registration rights agreement to provide holders of the Excel Vessel Share Consideration with certain customary demand, shelf and piggyback registration rights.

We refer to the Excel Transactions and the July 2014 Transactions as the “Transactions”.

For more information regarding the terms of the Excel Transactions and the amendment to the registration rights agreement, see Exhibit 99.4 to the Transaction 6-K.

Significant Shareholders as a Result of the Transactions

The percentages presented in this section do not give effect to this offering. A total of 54,104,200 of our common shares were issued to the various selling parties in the July 2014 Transactions, of which 45,460,324 shares were issued to Oaktree, and 8,643,876 shares were issued to owners of the Pappas Companies and Millennia Holdings. After the July 2014 Transactions, Oaktree was the beneficial owner of approximately 61.3% of our outstanding common shares, and the Pappas Shareholders were the beneficial owners of approximately 12.6% of our outstanding common shares.

Giving effect to the completion of the Excel Transactions (which we expect to occur in early 2015), and assuming the full distribution of the Excel Vessel Share Consideration to Excel’s equityholders, Oaktree will beneficially own 57.4% of our outstanding common shares, and the Angelo, Gordon will beneficially own 6.2% of our outstanding common shares. As a result of the issuance of the Excel Vessel Share Consideration, the Pappas Shareholders will beneficially own 9.3% of our outstanding common shares.

As noted above, under the Oaktree Shareholders Agreement, with certain limited exceptions, Oaktree effectively cannot vote more than 33% of our outstanding common shares (subject to adjustment under certain

circumstances), and the Pappas Shareholders are subject to a similar limitation under the Pappas Shareholders Agreement of 15% (subject to adjustment under certain circumstances).

Additional Financings and Loan Agreement Amendments Related to the Transactions

In connection with the Excel Transactions, we entered into a $231.0 million Excel Vessel Bridge Facility, which will be secured by 33 of the Excel Vessels, related bank accounts, earnings and issuances, and an equity pledge from each subsidiary that owns the 33 pledged Excel Vessels. It matures in February, 2016 and has various negative and financial maintenance covenants. We are using the proceeds of the Excel Vessel Bridge Facility to pay part of the cash portion of consideration in the Excel Transactions. As of December 31, 2014, we had $56.2 million outstanding under the Excel Vessel Bridge Facility, along with $164.5 million of total financing outstanding under the Citibank Facility, the DVB Facility, and the DNB Facility (each as defined and described below under “Recent Developments”), all of which was drawn to finance the closings of the 28 Excel Vessels that had been delivered as of that date (or refinance amounts originally drawn under the Excel Vessel Bridge Facility in respect of those Excel Vessels). For more information on the Excel Vessel Bridge Facility, see Exhibit 99.4 to the Transaction 6-K.

As a result of the July 2014 Transactions, we assumed an additional $208.2 million aggregate principal amount of vessel financing, representing the outstanding debt of the Oceanbulk Companies and the Pappas Companies as at July 11, 2014, all of which is secured by the vessels financed, some of which is guaranteed either by us or by certain of our subsidiaries. All of the vessels financing agreements have various negative and financial maintenance covenants. In addition, we also assumed bareboat charters with respect to four newbuilding vessels being built at Yangzijiang and five newbuilding vessels being built at SWS. For more information regarding these financing arrangements see Exhibit 99.2 to the Third Quarter 6-K, under Notes 8 and 16 to our unaudited interim condensed consolidated financial statements for the nine month period ended September 30, 2014.

In connection with the July 2014 Transactions, we amended our $85.0 million facility with Deutsche Bank AG Filiale Deutschlandgeschäft (the “Deutsche Bank Facility”), which is more fully described in Exhibit 99.2 to the Third Quarter 6-K under Note 8 to our unaudited interim condensed consolidated financial statements for the nine month period ended September 30, 2014, to make Star Bulk Carriers Corp. a guarantor under this facility and have the covenants apply to Star Bulk Carriers Corp., rather than Oceanbulk Shipping.

In connection with July 2014 Transactions, we also amended our $86.6 million facility with HSBC Bank plc. (the “HSBC Facility”), which is more fully described in Exhibit 99.2 to the Third Quarter 6-K under Note 8 to our unaudited interim condensed consolidated financial statements for the nine month period ended September 30, 2014, to make Star Bulk Carriers Corp. a guarantor under this facility and have the covenants apply to Star Bulk Carriers Corp., rather than Oceanbulk Shipping.

During July 2014, we obtained the consent of our lenders to complete the July 2014 Transactions.

RECENT DEVELOPMENTS

Dioriga Facility

In connection with July 2014 Transactions, on October 3, 2014, we amended our $20.0 million facility with HSBC, provided to Dioriga Shipping Co. (the “Dioriga Facility”), which is more fully described in Exhibit 99.2 to the Third Quarter 6-K under Note 8 to our unaudited interim condensed consolidated financial statements, to make Star Bulk Carriers Corp. a guarantor under this facility and to include covenants similar to those of our other vessel financing facilities.

DVB Facility

On October 31, 2014, as part of the Excel Transactions, we acquired 100% of the equity interests of Christine Shipco LLC, which is the owner of the vessel Christine (tbr Star Martha), one of the 34 Excel Vessels. In order to finance this acquisition, we entered into a credit facility with DVB Bank SE, Frankfurt (the “DVB Facility”). Definitive documentation for the DVB Facility was signed on October 30, 2014, and the amount drawn was $24.8 million. The drawn amount will be repaid in 24 quarterly principal payments of $0.9 million for the first four quarters and of $0.4 million for the remaining 20 quarters, with the first quarterly payment due

three months from the drawdown date, with a balloon installment of $12.2 million payable simultaneously with the 24th installment. The DVB Facility is secured by a first priority pledge of the membership interests of the Christine Shipco LLC and general and specific assignments. The DVB Facility is guaranteed by Star Bulk Carriers Corp. and contains negative and financial covenants customary for facilities of this type.

Excel Vessel CiT Facility

In October 2014, we executed a binding term sheet with CiT Finance LLC with respect to a new credit facility (the “Excel Vessel CiT Facility”) for financing to be secured on a first-priority basis by 11 of the older Excel Vessels we have acquired or are acquiring under the Vessel Purchase Agreement, consisting of nine Panamax and two Handymax vessels (the “Excel Collateral Vessels”). Definitive documentation for the Excel Vessel CiT Facility was signed on December 9, 2014, and the amount drawn was $30.0 million. Pursuant to an intercreditor agreement executed among the lenders under the Excel Vessel Bridge Facility and CiT, the Excel Collateral Vessels will also secure the Excel Vessel Bridge Facility on a second-priority basis. The borrowers under the Excel Vessel CiT Facility will be the various vessel-owning subsidiaries that own the Excel Collateral Vessels, and Star Bulk Carriers Corp. will be the guarantor. The Excel Vessel CiT Facility will mature in December 2016 and will be subject to quarterly amortization payments of $0.5 million, commencing on March 31, 2015, with a balloon installment equal to the outstanding amount under the Excel Vessel CiT Facility payable simultaneously with the last quarterly installment. The agreement governing the Excel Vessel CiT Facility contains negative, affirmative and financial maintenance covenants that are customary for facilities of this type.

Sinosure Facility

On December 22, 2014, we executed a term sheet with Deutsche Bank (China) Co., Ltd. Beijing Branch and HSBC Bank plc (the “Sinosure Facility”) for the financing of an aggregate amount of up to the lesser of $156.5 million or 68% of the fair market value of eight of our Ultramax dry bulk carrier vessels (Hulls HN NE 164 (tbn Honey Badger), HN NE 165 (tbn Wolverine), HN NE 196 (tbn Star Antares), HN NE 197 (tbn Star Lutas), HN 1080 (tbn Kennadi), HN 1081 (tbn Mackenzie), HN 1082 (tbn Night Owl), HN 1083 (tbn Early Bird)) (the “Sinosure Financed Vessels”), which are currently under construction by Jiangsu Yangzijiang Shipbuilding Co. Ltd and Nantong COSCO KHI Ship Engineering Co. Ltd., with expected delivery between February 2015 and November 2015. The financing will be available in eight separate tranches, one for each Sinosure Financed Vessel, and will be credit insured (95%) by China Export & Credit Insurance Corporation. The final loan documentation is expected to be executed before the end of February 2015. Each tranche will mature twelve years after each drawdown and will be repaid in 48 equal and consecutive quarterly installments. The Sinosure Facility will be secured by a first priority cross-collateralized mortgage over the Sinosure Financed Vessels and general and specific assignments and will be guaranteed by Star Bulk Carriers Corp. The agreement governing the Sinosure Facility will contain negative, affirmative and financial maintenance covenants that are customary for facilities of this type.

Senior Notes Offering

On November 6, 2014, we issued $50.0 million aggregate principal amount of 8.00% Senior Notes due 2019 (the “2019 Notes”). The 2019 Notes mature in November 2019 and are senior, unsecured obligations of Star Bulk Carriers Corp. The 2019 Notes are not guaranteed by any of our subsidiaries.

The 2019 Notes bear interest at a rate of 8.00% per annum, payable quarterly in arrears on the 15th of February, May, August and November of each year, commencing on February 15, 2015.

The 2019 Notes mature on November 15, 2019. We may redeem the 2019 Notes, in whole or in part, at any time on or after November 15, 2016 at a redemption price equal to 100% of the principal amount to be redeemed, plus accrued and unpaid interest to, but excluding, the redemption date. Prior to November 15, 2016, we may redeem the 2019 Notes, in whole or in part, at a price equal to 100% of their principal amount plus a make-whole premium and accrued interest to the date of redemption. In addition, we may redeem the 2019 Notes in whole, but not in part, at any time, at a redemption price equal to 100% of their principal amount to be redeemed, plus accrued and unpaid interest to, but excluding, the redemption date, if certain events occur involving changes in taxation.

The indenture governing the 2019 Notes requires us to maintain a maximum ratio of net debt to consolidated total assets and a minimum consolidated tangible net worth. The indenture governing the 2019

Notes also contains various negative covenants, including a limitation on asset sales and a limitation on restricted payments. The indenture governing the 2019 Notes also contains other customary terms and covenants, including that upon certain events of default occurring and continuing, either the Trustee or the holders of not less than 25% in aggregate principal amount of the 2019 Notes then outstanding may declare the entire principal amount of all the 2019 Notes plus accrued interest, if any, to be immediately due and payable. Upon certain change of control events, we are required to offer to repurchase the 2019 Notes at a price equal to 101% of their principal amount, plus accrued and unpaid interest to, but not including, the date of redemption. If we receive net cash proceeds from certain asset sales and do not apply them within a specified deadline, we will be required to apply those proceeds to offer to repurchase the 2019 Notes at a price equal to 101% of their principal amount, plus accrued and unpaid interest to, but not including, the date of redemption.

NIBC Facility

On November 7, 2014, we entered into a $32.0 million secured loan facility with NIBC Bank N.V. (the “NIBC Facility”) to partially finance the construction cost of two Ultramax bulk carriers currently under construction by JMU (Hulls HN 5040, tbn Star Acquarius and HN 5043, tbn Star Pisces), with expected delivery in May 2015 and July 2015, respectively. The NIBC Facility will be available in two tranches of $16.0 million and will mature six years after the signing date. Each tranche is expected to be drawn with the delivery of the relevant vessel and will be repayable in consecutive quarterly installments of $0.3 million, commencing three months after the drawdown, plus a balloon payment of $10.4 million for each of the two newbuilding vessels, both due in November 2020. The NIBC Facility is secured by a first priority cross collateralized mortgage over the financed vessels and general and specific assignments and is guaranteed by Star Bulk Carriers Corp. The NIBC Facility contains negative, affirmative and financial covenants customary for facilities of this type.

Citibank Facility

On November 20, 2014, we executed a binding term sheet with Citibank, N.A., London Branch (the “Citi Facility”) to provide financing in an amount of up to $100.0 million, in lieu of the Excel Vessel Bridge Facility, in connection with the acquisition of vessels Sandra (tbr Star Pauline), Lowlands Beilun (tbr Star Despoina), Star Angie, Star Sophia, Star Georgia, Star Kamila and Iron Kalypso (tbr Star Nina), which are seven of the Excel Vessels we have acquired or are acquiring (the “Citi Financed Excel Vessels”). Execution of the definitive documentation for Citi Facility was signed on December 22, 2014. The first tranche of $51.5 million was drawn on December 24, 2014, and the second tranche of $42.6 million is expected to be drawn in early 2015. We will use amounts drawn under the Citi Facility for the cash consideration of any Citi Financed Vessels that have not yet been delivered. For the Citi Financed Excel Vessels that we have already acquired, we will use amounts drawn under the Citi Facility to repay the amounts drawn under the Excel Vessel Bridge Facility in respect of those Citi Financed Excel Vessels. The Citi Facility matures at the earlier of (a) 60 months after the final drawdown and (b) December 30, 2019. The Citi Facility will be repaid in 20 equal, consecutive, quarterly principal payments of $3.4 million each, with the first installment due at the earlier of (i) three months after the drawdown of the second tranche and (ii) March 30, 2015, with a balloon installment of $26.3 million payable simultaneously with the 20th installment. The Citi Facility is secured by a first priority mortgage over the Citi Financed Excel Vessels and general and specific assignments and is guaranteed by Star Bulk Carriers Corp. The agreement governing the Citi Facility contains negative, affirmative and financial maintenance covenants that are customary for facilities of this type.

Heron Vessel Financing

In November 2014, we entered into a secured term loan agreement with CiT Finance LLC in order to partially finance the acquisition cost of the two Heron Vessels. The loan provides for up to $25.3 million of financing, which we drew in December 2014, when we took delivery of the Heron Vessels. The facility matures on June 30, 2019 and is repayable in 18 equal quarterly principal payments of $0.4 million per vessel. The first payment becomes due and payable on December 31, 2014. There is a balloon installment payable at maturity equal to the then outstanding amount of the loan. The facility is secured by a first priority mortgage over the financed vessels and general and specific assignments and will be guaranteed by Star Bulk Carriers Corp.

DNB Facility

On December 29, 2014, we entered into an agreement with DNB Bank ASA (the “DNB Facility”), to provide financing in an amount of $117.7 million, in lieu of the Excel Vessel Bridge Facility, in connection with the acquisition of vessels Star Nasia, Iron Beauty (tbr Star Monisha), Star Eleonora, Star Danai, Star Renee,

Star Markella, Star Laura, Star Moira, Ore Hansa (tbr Star Jennifer), Star Mariella, Star Helena and Star Maria, which are twelve of the Excel Vessels we have acquired or are acquiring (the “DNB Financed Excel Vessels”). An amount of $88.3 million was drawn on December 30, 2014, and the remaining amount is expected to be drawn in January 2015. We will use amounts drawn under the DNB Facility for the cash consideration of any DNB Financed Vessels that have not yet been delivered. For the DNB Financed Excel Vessels that we have already acquired, we will use amounts drawn under the DNB Facility to repay the amounts drawn under the Excel Vessel Bridge Facility in respect of those DNB Financed Excel Vessels. The DNB Facility matures at the earlier of (a) 60 months after the first drawdown and (b) January 31, 2020. Each tranche under the DNB Facility is repaid in 20 equal, consecutive, quarterly principal payments, with the first installment due three months after the first drawdown, and a balloon installment equal to 25% of the aggregate tranche payable simultaneously with the 20th installment. The DNB Facility is secured by a first priority mortgage over the DNB Financed Excel Vessels and general and specific assignments and is guaranteed by Star Bulk Carriers Corp. The agreement governing the DNB Facility contains customary negative, affirmative and financial maintenance covenants that are customary for facilities of this type.

New Services Agreement with Interchart

In November 2014, we entered into a new services agreement with Interchart Shipping Inc. (“Interchart”) for chartering, brokering and commercial services for all of our vessels for a monthly fee of $0.3 million. The agreement is effective from October 1, 2014 until March 31, 2015. The previous agreement with Interchart, dated February 25, 2014, was terminated when this agreement became effective. See “Certain Relationships and Related Party Transactions—New Services Agreement with Interchart.”

Excel Vessel Deliveries

As of December 31, 2014, 28 of the Excel Vessels had been delivered to us in exchange for 25,659,425 common shares and $248.9 million of cash. As of December 31, 2014, we had drawn approximately $220.7 million to finance the cash consideration paid in connection with the Excel Vessels delivered to us as of that date.

Sale of Vessel

On December 17, 2014, we entered into an agreement with a third party to sell the vessel Star Kim, one of the Excel Vessels, for market value. We expect to deliver this vessel to its new owner in January 2015.

Outsourcing of Certain Procurement Services

As of January 1, 2015, we have engaged Ship Procurement Service, an unaffiliated third party company, to provide to our fleet certain procurement services at a daily fee of $295 per vessel.

Payment for Indomitable

On December 30, 2014, in anticipation of the delivery of the Indomitable to us on January 8, 2015, we made a payment of $34.9 million, which will be held in escrow until the delivery of the vessel to us, of which $32.5 million was drawn under the BNP Facility, which is more fully described in Exhibit 99.2 to the Third Quarter 6-K under Note 8 to our unaudited interim condensed consolidated financial statements for the nine month period ended September 30, 2014, and the remaining amount was financed using existing cash.

Certain Preliminary Financial Information as of December 31, 2014    

As of December 31, 2014, we had total cash of $99.7 million, total debt of $861.8 million and total net book value of vessels on-the-water of $1.44 billion. The foregoing financial information is preliminary and is based on management’s estimates, and has not been subject to our financial statements closing process or any audit or review by our independent accountants. As a result, such financial information may be subject to change due to the completion of our financial statements closing process and audit process. Additionally, the foregoing financial information may differ from future results, see “Risk Factors—Risks Related to Our Industry—Charterhire rates for dry bulk vessels are volatile and have declined significantly since their historic highs and may remain at low levels or decrease in the future, which may adversely affect our earnings, revenue and profitability and our ability to comply with our loan covenants.”

THE OFFERING

These shares do not reflect:

On an as-adjusted basis, giving effect to this offering (assuming the purchases of common shares by the Significant Shareholders occur at the closing price of our common shares of $6.07 on January 7, 2015) and assuming all 29,917,312 common shares comprising the Excel Vessel Share Consideration are distributed by Excel to its equityholders, Oaktree, Angelo, Gordon, Monarch and the Pappas Shareholders, including the Pappas Affiliates, would beneficially own approximately 57.4%, 6.2%, 5.4% and 8.4%, respectively, of our outstanding common shares (or approximately 56.9%, 6.1%, 5.4% and 8.4%, respectively, of our outstanding common shares if the underwriters exercise their option in full). Prior to this offering, giving effect to the distribution of the Excel Vessel Share Consideration to the Excel equityholders, Oaktree, Angelo, Gordon, Monarch and the Pappas Shareholders would beneficially own approximately 57.4%, 6.2%, 5.4% and 9.3%, respectively of our outstanding common shares.

SUMMARY HISTORICAL AND PRO FORMA FINANCIAL AND OPERATING INFORMATION

Set forth below are the summary historical and pro forma consolidated financial and other data of Star Bulk and its consolidated subsidiaries for the periods and as of the dates indicated.

The summary historical consolidated financial data as of and for the years ended December 31, 2012 and 2013 have been derived from our consolidated financial statements as of such dates and for such years, which have been audited by Ernst & Young (Hellas) Certified Auditors Accountants S.A., as indicated in the 2013 20-F. The summary historical consolidated financial data as of and for the year ended December 31, 2011 have been derived from our consolidated financial statements as of such date and for such year, which have been audited by Deloitte Hadjipavlou, Sofianos & Cambanis S.A., as indicated in the 2013 20-F.

The summary historical consolidated financial data as of and for the nine months ended September 30, 2013 and 2014 have been derived from our consolidated financial statements as of such dates and for such periods included in our unaudited interim condensed consolidated financial statements for the nine months ended September 30, 2014 (included in Exhibit 99.2 to the Third Quarter 6-K), which are unaudited but which have been prepared on the same basis as our audited consolidated financial statements and, in the opinion of our management, reflect all adjustments, consisting of normal recurring adjustments, necessary for a fair statement of the information set forth therein.

The summary historical consolidated financial data below should be read in conjunction with the “Management’s Discussion and Analysis of Financial Condition and Results of Operations,” and our consolidated financial statements and related notes included in the 2013 20-F, as well as the “Management’s Discussion and Analysis of Financial Condition and Results of Operations,” and our consolidated financial statements and related notes included in Exhibit 99.1 to the Third Quarter 6-K.

The summary pro forma financial information for the year ended December 31, 2013 and the nine months ended September 30, 2014 have been derived from the unaudited pro forma condensed financial information contained in this prospectus. The acquisition of Oceanbulk and the Pappas Companies has already been reflected in Star Bulk's historical condensed combined balance sheet, and therefore no pro forma balance sheet data is presented. The summary pro forma statements of operations for the year ended December 31, 2013 and the nine months ended September 30, 2014 give effect to the Merger and the Pappas Transaction as if such transactions closed on January 1, 2013. The summary pro forma financial information does not reflect the acquisition of the Heron Vessels, the Excel Vessels or any of the other Excel Transactions, since our financial statements reflect each Excel Vessel and Heron Vessel as the purchase of an asset and therefore the operations of each Excel Vessel and Heron Vessel is reflected in our financial statements from the date it is transferred to us. See “Unaudited Pro Forma Condensed Combined Statement of Operations of Star Bulk.”

The summary pro forma financial information below was derived from and should be read in conjunction with Star Bulk’s audited consolidated financial statements and the related notes included in the 2013 20-F for the year ended December 31, 2013, Star Bulk’s unaudited interim condensed consolidated financial statements for the nine months ended September 30, 2014 (included in Exhibit 99.2 to the Third Quarter 6-K)and in conjunction with Oceanbulk’s audited combined financial statements and the related notes included in Exhibit 99.2 to the Transaction 6-K.

Adjusted EBITDA, is calculated by further adjusting EBITDA to exclude the effects of various items such as non-cash items affecting our earnings, including but not limited to stock based compensation expense, vessel impairment losses, gains or losses recognized upon the sale of vessels, bad debt expenses due to the impairment of receivables, gains or losses on the termination of time charter agreements and changes in fair value of derivatives, and other items such as the costs associated with the July 2014 Transactions. We excluded the above-described items to derive adjusted EBITDA because we believe that these items do not reflect the operational cash inflows and outflows of our business on an ongoing basis. The derivation of adjusted EBITDA is set forth below. Together, we refer to EBITDA and adjusted EBITDA as our “EBITDA-Based Measures.”

Our EBITDA-Based Measures do not represent and should not be considered as alternatives to net income or cash flow from operations, as determined by United States generally accepted accounting principles, or U.S. GAAP, and our calculation of our EBITDA-Based Measures may not be comparable to those reported by other companies. Our EBITDA-based Measures are included in this prospectus because they are tools with which we assess our liquidity position. They are also used by our lenders as measures of our compliance with certain loan covenants.

We believe that our EBITDA-Based Measures are used by investors and other users of our financial statements as supplemental financial measures that, when viewed with our U.S. GAAP financial information and the accompanying reconciliations, provide additional information that is useful to gain an understanding of the factors and trends affecting our ability to incur and service debt and fund dry docking charges and other capital expenditures. We also believe the disclosure of EBITDA-Based Measures helps investors meaningfully evaluate and compare our cash flow generating capacity from quarter to quarter and year to year.

Other companies may calculate their EBITDA and adjusted EBITDA differently, which may limit their usefulness as comparative measures. We view our EBITDA-Based Measures as liquidity measures and, as such, we believe that the U.S. GAAP financial measure most directly comparable to these measures is net cash from operating activities. Because our EBITDA-Based Measures are not measures calculated in accordance with U.S. GAAP, they should not be considered in isolation or as substitutes for operating income, net income or loss, net cash from operating, investing and financing activities or other income or cash flow statement data prepared in accordance with U.S. GAAP. You should therefore not place undue reliance on our EBITDA-Based Measures or ratios calculated using those measures. Our U.S. GAAP-based measures can be found in our financial statements and the related notes thereto included elsewhere in this prospectus.

Our EBITDA-Based Measures have limitations as analytical tools. Some of these limitations are:

We compensate for these limitations by using our EBITDA-Based Measures along with other comparative tools, together with U.S. GAAP measures, to assist in the evaluation of our liquidity and operating performance. Such U.S. GAAP measures include operating income/ (loss), net income/(loss), cash flows from operations and other cash flow data.

The following table reconciles EBITDA and Adjusted EBITDA to our net cash provided by operating activities, the most directly comparable U.S. GAAP measure, for the periods presented:

RISK FACTORS

An investment in our common shares involves a high degree of risk, including the risks we face described in the accompanying prospectus and the documents incorporated by reference herein. Our business, financial condition, and results of operations could be materially and adversely affected by any of these risks. The trading price of our common shares could decline due to any of these risks, and you may lose all or part of your investment. This prospectus, the accompanying prospectus, and the documents incorporated by reference herein also contain forward-looking statements that involve risks and uncertainties. Our actual results could differ materially from those anticipated in these forward-looking statements as a result of certain factors, including the risks we face described in the accompanying prospectus and the documents incorporated by reference herein.

Before you decide to invest in our common shares, you should carefully consider the risks and the discussion of risks under the heading “Risk Factors” of the accompanying prospectus and in our Annual Report for the year ended December 31, 2013 on Form 20-F, filed with the Commission on March 21, 2014 and incorporated by reference herein, as well as other information included in this prospectus, the accompanying prospectus and the documents we have incorporated by reference in this prospectus that summarize the risks that may materially affect our business. Please refer to the sections entitled “Where You Can Find Additional Information” in this prospectus and in the accompanying prospectus for discussions of these other filings.

Risks Related to Our Industry

Charterhire rates for dry bulk vessels are volatile and have declined significantly since their historic highs and may remain at low levels or decrease in the future, which may adversely affect our earnings, revenue and profitability and our ability to comply with our loan covenants.

The dry bulk shipping industry is cyclical with high volatility in charterhire rates and profitability. The degree of charterhire rate volatility among different types of dry bulk vessels has varied widely; however, the continued downturn in the dry bulk charter market has severely affected the entire dry bulk shipping industry and charterhire rates for dry bulk vessels have declined significantly from historically high levels. In the past, time charter and spot market charter rates for dry bulk carriers have declined below operating costs of vessels. The BDI, a daily average of charter rates for key dry bulk routes published by the Baltic Exchange Limited, which has long been viewed as the main benchmark to monitor the movements of the dry bulk vessel charter market and the performance of the entire dry bulk shipping market, declined 94% in 2008 from a peak of 11,793 in May 2008 to a low of 663 in December 2008 and has remained volatile since then. The BDI recorded a record low of 647 in February 2012. While the BDI has since increased from these low levels and has fluctuated in a range between 698 and 2,337 from December 2012 through and including December 2014, due to recent downward volatility, the BDI has ranged from 782 to 1,137 during December 2014, and the dry bulk market remains volatile.

Fluctuations in charter rates result from changes in the supply of and demand for vessel capacity and changes in the supply of and demand for the major commodities carried by water internationally. Because the factors affecting the supply of and demand for vessels are outside of our control and are unpredictable, the nature, timing, direction and degree of changes in industry conditions are also unpredictable. Since we charter our vessels principally in the spot market, we are exposed to the cyclicality and volatility of the spot market. Spot market charterhire rates may fluctuate significantly based upon available charters and the supply of and demand for seaborne shipping capacity, and we may be unable to keep our vessels fully employed in these short-term markets. Alternatively, charter rates available in the spot market may be insufficient to enable our vessels to operate profitably. A significant decrease in charter rates would also affect asset values and adversely affect our profitability, cash flows and our ability to pay dividends, if any.

Factors that influence demand for dry bulk vessel capacity include:

Factors that influence the supply of vessel capacity include:

In addition to the prevailing and anticipated freight rates, factors that affect the rate of newbuilding, scrapping and laying-up include newbuilding prices, secondhand vessel values in relation to scrap prices, costs of bunkers and other operating costs, costs associated with classification society surveys, normal maintenance and insurance coverage, the efficiency and age profile of the existing dry bulk fleet in the market and government and industry regulation of maritime transportation practices, particularly environmental protection laws and regulations. These factors influencing the supply of and demand for shipping capacity are outside of our control, and we may not be able to correctly assess the nature, timing and degree of changes in industry conditions.

We anticipate that the future demand for our dry bulk vessels will be dependent upon economic growth in the world’s economies, including China and India, seasonal and regional changes in demand, changes in the capacity of the global dry bulk fleet and the sources and supply of dry bulk cargo to be transported by sea. Given the number of new dry bulk carriers currently on order with the shipyards, the capacity of the global dry bulk carrier fleet seems likely to increase and there can be no assurance as to the timing or extent of future economic growth. Adverse economic, political, social or other developments could have a material adverse effect on our business and operating results.

Risks Related to this Offering and Ownership of our Common Shares

We cannot assure you that we will be able to raise equity sufficient to meet our future capital and operating needs.

We expect that the net proceeds of this offering will be approximately $       million, after deducting estimated commissions and offering expenses; however we cannot assure you that we will be able to sell that amount of our common shares. Furthermore, even if we raise the net proceeds discussed above, we cannot assure you that such proceeds will be sufficient to meet our ongoing capital and operating needs. As of December 31, 2014, we had obtained commitments for $686.7 million of secured debt for 24 newbuilding vessels (which includes the debt drawn in relation to the delivery of the Indomitable, see “Recent Developments—Payment for Indomitable”), we were in negotiations for an additional $292.5 million of secured debt for nine newbuilding vessels, and we were targeting an additional $65.0 million of secured debt for the remaining two newbuilding vessels.

Investors may experience significant dilution as a result of this offering and future offerings.

After this offering, the sale of shares of our common stock in the public market, or the perception that such sales could occur, could harm the prevailing market price of shares of our common stock. These sales, or the possibility that these sales may occur, also might make it more difficult for us to sell equity securities in the future at a time and at a price that we deem appropriate.

Based on the offer and sale of        common shares, we would have        common shares outstanding, which as of December 31, 2014 represents an increase of approximately    % in our issued and outstanding common shares. Because the sales of the shares offered hereby will be made directly into the market or in negotiated transactions, the prices at which we sell these shares will vary and these variations may be significant. Purchasers of the shares we sell, as well as our existing shareholders, will experience significant dilution if we sell shares at prices significantly below the price at which they invested.

In connection with this offering we have agreed that we will not, subject to certain exceptions, during the period from the date of the underwriting agreement through the date that is 60 days subsequent to the date thereof, offer, sell, contract or otherwise dispose of, or file any registration statement under the Securities Act in respect of, securities convertible into or exercisable or exchangeable for our common shares. Each of our Significant Shareholders, directors and executive officers has entered into a similar agreement with the representatives of the underwriters, subject to certain exceptions, including, but not limited to, being permitted to pledge their common shares as collateral or security for foreign exchange swaps and custody agreements and to make transfers of pledged common shares as a result of foreclosure thereupon. We have granted equity awards under the 2014 Equity Incentive Plan. As of September 30, 2014, we have granted 424,407 common shares to certain of our directors, officers and employees. We may file one or more registration statements on Form S-8 under the Securities Act to register the shares of common stock subject to issuance under the 2014 Equity Incentive Plan. Any such Form S-8 registration statements will automatically become effective upon filing. Once these shares are registered, they can be sold in the public market upon issuance, subject to restrictions under the securities laws applicable to resales by affiliates.

The market price of our shares of common stock could drop significantly if the holders of our shares sell them or are perceived by the market as intending to sell them. These factors could also make it more difficult for us to raise additional funds through future offerings of our shares of common stock or other securities. In the future, we may also issue our securities in connection with investments or acquisitions. The amount of shares of our common stock issued in connection with an investment or acquisition could constitute a material portion of our then-outstanding shares of our common stock. Any issuance of additional securities in connection with investments or acquisitions may result in additional dilution to you. In addition, we may offer additional common shares in the future, whether or not in connection with investments or acquisitions, which may result in additional significant dilution.

The market price of our common shares has fluctuated widely and may fluctuate widely in the future, or there may be no continuing public market for you to resell our common stock.

The market price of our common stock has fluctuated widely since our common shares began trading on the Nasdaq Global Select Market in December 2007, and may continue to do so as a result of many factors such as actual or anticipated fluctuations in our quarterly and annual results and those of other public companies in our industry, mergers and strategic alliances in the shipping industry, market conditions in the shipping industry, changes in government regulation, shortfalls in our operating results from levels forecast by securities analysts, announcements concerning us or our competitors and the general state of the securities market. Further, there may be no continuing active or liquid public market for our common stock.

If the market price of our common shares decreases below $5.00 per share, under stock exchange rules, our shareholders will not be able to use such shares as collateral for borrowing in margin accounts. This inability to continue to use our common shares as collateral may lead to sales of such shares creating downward pressure on and increased volatility in the market price of our common shares.

The shipping industry has been highly unpredictable and volatile. The market for common shares in this industry may be equally volatile. Therefore, we cannot assure you that you will be able to sell any of our common shares you may have purchased at a price greater than or equal to its original purchase price, or that you will be able to sell them at all.

Beginning in 2015 we have to pay U.S. federal income tax on our U.S. source income.

Under the U.S. Internal Revenue Code of 1986, as amended (the “Code”), 50% of the gross shipping income of a non-U.S. corporation, such as ourselves, that is attributable to transportation that begins or ends, but that does not both begin and end, in the United States is characterized as “United States source gross shipping income,” and such income is subject to a 4% U.S. federal income tax without allowance for any deductions, unless the corporation qualifies for exemption from U.S. federal income taxation under Section 883 of the Code and the Treasury Regulations promulgated thereunder.

We do not expect to qualify for the exemption from U.S. federal income taxation under Section 883 of the Code beginning in 2015 and for the foreseeable future. Accordingly, we will be subject to the 4% U.S. federal income tax on our United States source gross shipping income. If a significant portion of our income is United States source gross shipping income, the imposition of such tax could have a negative effect on our business and would result in decreased earnings available for distribution to our shareholders. In 2013, if we had not qualified for such an exemption, we would have owed approximately $150,000 in U.S. federal income tax. We expect our United States source gross shipping income to increase in 2015 due to an increase in the size of our fleet, and, accordingly, we expect our U.S. federal income tax liability in 2015 to be larger than $150,000. Please see the section of this prospectus supplement entitled “Material United States Federal Income Tax Considerations—U.S. Federal Income Tax Considerations—U.S. Federal Income Taxation of the Company.”

The Internal Revenue Service could treat us as a “passive foreign investment company,” which could have adverse U.S. federal income tax consequences to U.S. shareholders.

A non-U.S. corporation will be treated as a “passive foreign investment company” (a “PFIC”) for U.S. federal income tax purposes if either (1) at least 75% of its gross income for any taxable year consists of certain types of “passive income” (e.g., dividends, interest, capital gains and rents derived other than in the active conduct of a rental business) or (2) at least 50% of the average value of the corporation’s assets produce or are held for the production of passive income. For purposes of determining the PFIC status of a non-U.S. corporation, income earned in connection with the performance of services does not constitute passive income, but rental income generally is treated as passive income unless the non-U.S. corporation is treated under specific rules as deriving its rental income in the active conduct of a trade or business. We intend to take the position that income we derive from our voyage and time chartering activities is services income, rather than rental income, and accordingly, that such income is not passive income for purposes of determining our PFIC status. Based on this characterization of income from voyage and time charters and the expected composition of our income and assets, we believe that we currently are not a PFIC, and we do not expect to become a PFIC in the future. Additionally, we believe that our contracts for newbuilding vessels are not assets held for the production of passive income, because we intend to use these vessels for voyage and time chartering activities. However, there is no direct legal authority under the PFIC rules addressing our characterization of income from our voyage and time chartering activities nor our characterization of contracts for newbuilding vessels. Moreover, the determination of PFIC status for any year can only be made on an annual basis after the end of such taxable year and will depend on the composition of our income, assets and operations from time to time. Because of the above described uncertainties, there can be no assurance that the Internal Revenue Service will not challenge the determination made by us concerning our PFIC status or that we will not be a PFIC for any taxable year.

If we were classified as a PFIC for any taxable year during which a U.S. shareholder owns common shares (regardless of whether we continue to be a PFIC), the U.S. shareholder would be subject to special adverse rules, including taxation at maximum ordinary income rates plus an interest charge on both gains on sale and certain dividends, unless the U.S. shareholder makes an election to be taxed under an alternative regime. Certain elections may be available to U.S. shareholders if we were classified as a PFIC. Please see the section of this prospectus supplement entitled “Material United States Federal Income Tax Considerations — U.S. Federal Income Tax Considerations — U.S. Federal Income Taxation of U.S. Holders — Passive Foreign Investment Company Considerations” for a more comprehensive discussion of the U.S. federal income tax consequences to U.S. shareholders if we are treated as a PFIC.

USE OF PROCEEDS

We estimate that the net proceeds of this offering to us will be approximately $    million, or $    million if the underwriters exercise in full their option to purchase additional shares after deducting the underwriting discounts and commissions and our estimated offering expenses. We will use the net proceeds from the sale of the common shares offered by this prospectus for general corporate purposes. These general corporate purposes may include, among other things, additions to our working capital, capital expenditures (which includes our newbuilding program), research and development, repayment of debt, repurchases of stock or the financing of possible acquisitions and investments.

CAPITALIZATION

The following table sets forth our capitalization table as of September 30, 2014, on:

Other than the adjustments described above, there have been no significant adjustments to our capitalization since September 30, 2014. This table should be read in conjunction with the unaudited interim condensed consolidated financial statements and the related notes for the nine months ended September 30, 2014, included in Exhibit 99.2 to the Third Quarter 6-K, which is incorporated by reference herein, and the consolidated financial statements and related notes included in our annual report for the year ended December 31, 2013, on Form 20-F filed with the Commission on March 21, 2014 and incorporated by reference herein.

PER SHARE MARKET PRICE INFORMATION

Since December 3, 2007 our common shares have traded on the Nasdaq Global Select Market under the symbol “SBLK”. You should carefully review the high and low prices of Star Bulk common shares in the table below and under the heading Item 9. “The Offer and Listing” in our annual report on Form 20-F for the year ended December 31, 2013, which is incorporated by reference herein. As of December 31, 2014, there were 113 holders of record of our common stock.

The table below sets forth the high and low prices for each of the periods indicated for our shares of common stock as reported by the NASDAQ Global Select Market.

DIVIDEND POLICY

Initially, we do not intend to pay dividends to the holders of our common shares but rather to invest our available cash in the growth of our fleet and development of our business. We will continue to assess our dividend policy and our Board of Directors may determine it is in the best interest of the Company to pay dividends in the future. Our Board of Directors may review and amend our dividend policy from time to time in light of our plans for future growth and other factors. Any dividends paid by us will be income to a U.S. shareholder.

We are a holding company with no material assets other than the equity interests in our wholly owned subsidiaries. As a result, our ability to pay dividends depends on our subsidiaries and their ability to distribute funds to us. Our credit facilities and the indenture governing the 2019 Notes have restrictions on our ability, and the ability of certain of our subsidiaries, to pay dividends in the event of a default or breach of covenants under the relevant credit facility agreement, and some of our credit facilities prohibit our subsidiaries from paying any dividends until March 31, 2015. Under such circumstances, certain of our subsidiaries may not be able to pay dividends so long as we are in default or have breached certain covenants of the credit facility without our lender’s consent or waiver of the default or breach. In addition, Marshall Islands law generally prohibits the payment of dividends (i) other than from surplus (retained earnings and the excess of consideration received for the sale of shares above the par value of the shares) or (ii) when a company is insolvent or (iii) if the payment of the dividend would render the company insolvent.

UNAUDITED PRO FORMA CONDENSED COMBINED STATEMENTS OF
OPERATIONS OF STAR BULK

On July 11, 2014, pursuant to an Agreement and Plan of Merger, dated as of June 16, 2014 (as amended from time to time, the “Merger Agreement”), Star Bulk Carriers Corp. (“Star Bulk”) completed a transaction with Oaktree Dry Bulk Holdings LLC (including affiliated funds, “Oaktree”) and Millennia Holdings LLC (“Millennia Holdings”, and together with Oaktree, the “Sellers”) that resulted in a merger of two of Star Bulk’s subsidiaries with Oceanbulk Shipping LLC (“Oceanbulk Shipping”) and Oceanbulk Carriers LLC (“Oceanbulk Carriers” and, together with Oceanbulk Shipping, “Oceanbulk”) (the “Merger”). At the time of the Merger, Oceanbulk owned and operated a fleet of 12 dry bulk carrier vessels and owned contracts for the construction of 25 newbuilding dry bulk vessels fuel-efficient Eco-type vessels (two of which, Peloreus and Leviathan were delivered on July 22, 2014 and September 19, 2014, respectively) at shipyards in Japan and China. The consideration paid by Star Bulk in the Merger was 48,395,766 common shares.

The agreement governing the Merger also provides for the acquisition (the “Heron Transaction”) of two Kamsarmax vessels (the “Heron Vessels”), from Heron Ventures Ltd. (“Heron”), a limited liability company incorporated in Malta. Star Bulk issued 2,115,706 of its common shares into escrow as consideration for the Heron Vessels. The common shares are expected to be released by early 2015 from escrow to the Sellers under the Merger Agreement following the delivery of the Heron Vessels to Star Bulk on December 5, 2014. In addition to the issued shares, in November 2014, Star Bulk entered into a loan agreement with CiT Finance LLC for $25.3 million, to finance the cash consideration related to the acquisition of the Heron Vessels. Pursuant to the agreement governing the Merger Agreement, Star Bulk is to have final net indebtedness in connection with the Heron Vessels of $25.0 million, with any deficit or surplus being settled with the Sellers after distribution of the Heron Vessels to Star Bulk.

In addition, concurrently with the Merger, Star Bulk completed a transaction (the “Pappas Transaction”), in which it acquired all of the issued and outstanding shares of Dioriga Shipping Co. and Positive Shipping Company (collectively, the “Pappas Companies”), which were entities owned and controlled by affiliates of the family of Mr. Pappas. At the time of the Merger, the Pappas Companies owned and operated a dry bulk carrier vessel (Tsu Ebisu) and had a contract for the construction of a newbuilding dry bulk carrier vessel, HN 5016 (tbn Indomitable) which was delivered to us on January 8, 2015. The consideration paid by Star Bulk in the Pappas Transaction was 3,592,728 common shares.

The accompanying unaudited pro forma condensed combined statements of operations of Star Bulk reflect:

All of the foregoing transactions are referred to as the “Pro Forma Transactions.”

The Merger and the Pappas Transaction have been reflected in the unaudited pro forma condensed combined financial information as purchases of businesses pursuant to Financial Accounting Standards Board (FASB) Accounting Standards Codification Topic 805, “Business Combinations” (“ASC Topic 805”). In addition, on December 5, 2014 Star Bulk took delivery of the Heron Vessels, for which, as of September 30, 2014, Star Bulk had issued 2,115,706 common shares into escrow and recorded a value of $25.1 million under Advances for vessels under construction and acquisition of vessels.

The accompanying unaudited pro forma condensed combined statements of operations of Star Bulk do not reflect the acquisition of the Heron Vessels or the Excel Vessels, since the financial statements of Star Bulk reflect each Excel Vessel and Heron Vessel as the purchase of an asset and therefore the operations of each Excel Vessel and Heron Vessel are reflected in Star Bulk’s financial statements from the date it is transferred to Star Bulk.

The unaudited pro forma condensed combined statements of operations for the year ended December 31, 2013, and nine months ended September 30, 2014, are presented in thousands of U.S. dollars and give effect to the Pro Forma Transactions as if such transactions closed on January 1, 2013. The acquisition of Oceanbulk and the Pappas Companies has already been reflected in Star Bulk's historical condensed combined balance sheet, and therefore no pro forma balance sheet data is presented.

These unaudited pro forma condensed combined statements of operations are being presented for illustrative purposes only and, therefore, are not necessarily indicative of the financial position or results of operations that might have been achieved had the Pro Forma Transactions actually occurred on January 1, 2013. They are not necessarily indicative of the results of operations of Star Bulk that may, or may not be expected to occur in the future. The unaudited pro forma condensed combined statements of operations do not reflect any special items such as payments pursuant to change-of-control provisions or restructuring and integration costs that may be incurred as a result of the Pro Forma Transactions.

The following unaudited pro forma condensed combined statements of operations were derived from and should be read in conjunction with Star Bulk’s audited consolidated financial statements and the related notes included in Star Bulk’s Annual Report on Form 20-F for the year ended December 31, 2013, filed with the SEC on March 21, 2014 and Star Bulk’s unaudited interim condensed consolidated financial statements as of and for the nine months ended September 30, 2014, which are contained in Exhibit 99.2 to the Third Quarter 6-K.

The cost of the acquisition of the Oceanbulk Companies and the Pappas Companies has been allocated to the estimated fair values of the identifiable assets and liabilities of the Oceanbulk Companies and the Pappas Companies pursuant to the acquisition method of accounting prescribed by ASC Topic 805, as further discussed in Note 1 to Star Bulk’s unaudited condensed consolidated statement of operations for the nine-month period ended September 30, 2014. The acquisition cost of the Pro Forma Transactions and the value of the advance, provided concurrently with the Merger, for the acquisition of the Heron Vessels through the issuance, in escrow, of 2,115,706 of Star Bulk’s common shares are based on the average closing market price of Star Bulk’s common shares, as determined over a period of two trading days before and two trading days after, and inclusive, of July 11, 2014.

STAR BULK CARRIERS CORP
UNAUDITED PRO FORMA CONDENSED COMBINED STATEMENT OF OPERATIONS
FOR THE NINE MONTHS ENDED SEPTEMBER 30, 2014