UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

WASHINGTON, D.C. 20549

SCHEDULE 14A

Proxy Statement Pursuant to Section 14(a)

of the Securities Exchange Act of 1934 (Amendment No.     )

Filed by the Registrant    x

Filed by a Party other than the Registrant    ¨

Check the appropriate box:

OLIN CORPORATION

(Name of Registrant as Specified In Its Charter)

(Name of Person(s) Filing Proxy Statement, if other than the Registrant)

Payment of Filing Fee (Check the appropriate box):

Notes:

Reg. Section 240.14a-101.

SEC 1913 (3-99)

190 CARONDELET PLAZA, SUITE 1530, CLAYTON, MISSOURI 63105

March 9, 2011

Dear Olin Shareholder:

We cordially invite you to attend our 2011 annual meeting of shareholders on April 28, 2011.

This booklet includes the notice and proxy statement, which describes the business we will conduct at the meeting and provides information about Olin that you should consider when you vote your shares. We have not planned a communications segment or any presentations for the 2011 annual meeting.

Whether or not you plan to attend, it is important that your shares are represented and voted at the annual meeting. If you do not plan to attend the annual meeting, you may vote your shares on the Internet, by telephone or by completing and returning the proxy card in the enclosed envelope. If you plan to attend the annual meeting, you will need to bring the upper half of your proxy card to use as your admission ticket for the meeting.

At last year’s annual meeting more than 92% of our shares were represented in person or by proxy. We hope for the same high level of representation at this year’s meeting and we urge you to vote as soon as possible.

Sincerely,

Joseph D. Rupp

Chairman, President and

Chief Executive Officer

YOUR VOTE IS IMPORTANT

We urge you to promptly vote the shares on the Internet, by

telephone or by completing, signing, dating and returning

your proxy card in the enclosed envelope.

OLIN CORPORATION

(Name of Registrant as Specified In Its Charter)

(Name of Person(s) Filing Proxy Statement, if other than the Registrant)

Payment of Filing Fee (Check the appropriate box):

Notes:

Reg. Section 240.14a-101.

SEC 1913 (3-99)

190 CARONDELET PLAZA, SUITE 1530, CLAYTON, MISSOURI 63105

March 12, 2012

Dear Olin Shareholder:

We cordially invite you to attend our 2012 annual meeting of shareholders on April 26, 2012.

This booklet includes the notice and proxy statement, which describes the business we will conduct at the meeting and provides information about Olin that you should consider when you vote your shares. We have not planned a communications segment or any presentations for the 2012 annual meeting.

Whether or not you plan to attend, it is important that your shares are represented and voted at the annual meeting. If you do not plan to attend the annual meeting, you may vote your shares on the Internet, by telephone or by completing and returning the proxy card in the enclosed envelope. If you plan to attend the annual meeting, you will need to bring the upper half of your proxy card to use as your admission ticket for the meeting.

At last year’s annual meeting more than 93% of our shares were represented in person or by proxy. We hope for the same high level of representation at this year’s meeting and we urge you to vote as soon as possible.

Sincerely,

Joseph D. Rupp

Chairman, President and

Chief Executive Officer

YOUR VOTE IS IMPORTANT

We urge you to promptly vote the shares on the Internet, by

telephone or by completing, signing, dating and returning

your proxy card in the enclosed envelope.

OLIN CORPORATION

Notice of Annual Meeting of Shareholders

Clayton, Missouri

March 9, 201112, 2012

OLIN CORPORATION

PROXY STATEMENT

ANNUAL MEETING OF SHAREHOLDERS

To be Held April 28, 201126, 2012

GENERAL QUESTIONS

Why did I receive this proxy statement?

You received this proxy statement because you owned shares of Olin common stock, par value $1 per share, which we sometimes refer to as common stock, at the close of business on February 28, 2011.29, 2012. Olin’s board of directors is asking you to vote at the 20112012 annual meeting FOR each of the director nominees identified in Item 1 and FOR Items 2 and 4 and FOR a one-year frequency under Item 3 listed in the notice of the annual meeting of shareholders. This proxy statement describes the matters on which we would like you to vote and provides information so that you can make an informed decision.

When was this proxy material mailed to shareholders?

We began to mail the proxy statement and form of proxy to shareholders on or about March 9, 2011.12, 2012.

What if I have questions?

If you have questions, please write them down and send them to the Secretary at Olin’s principal executive office at 190 Carondelet Plaza, Suite 1530, Clayton, MO 63105.

What will I be voting on?

You will be voting on:

The proposal to ratify the appointment of KPMG LLP as Olin’s independent registered public accounting firm for 20112012 is considered a discretionary item for which a broker will have discretionary power if you do not give instructions with respect to this proposal. The proposals to elect directors and to conduct a non-bindingan advisory vote on approval ofto approve the compensation for named executive officers and to conduct a non-binding vote on the frequency of a shareholder vote on executive compensation are non-routine matters for which a broker will not have discretionary voting power and for which specific instructions from beneficial owners are required. As a result, a broker will not be allowed to vote on the election of directors or the proposalsproposal to approve the compensation for named executive officers or the

frequency of a shareholder vote on executive compensation on behalf of its beneficial owner customers if the customers do not return specific voting instructions. If you are a shareholder that holds shares through a broker, please provide specific voting instructions to your broker.

Could other matters be voted on at the annual meeting?

As of March 9, 2011,12, 2012, the items listed in the preceding question are the only matters being considered. If any other matters are properly presented for action, the persons named in the accompanying form of proxy will vote the proxy in accordance with their bestgood faith business judgment and opinion as to what is in the best interests of Olin.

How does the board recommend I vote on the proposals?

The board recommends a vote FOR each of the director nominees identified in Item 1 and FOR Items 2 and 4 and FOR a one-year frequency under Item 3.

How can I obtain directions to be able to attend the annual meeting and vote in person?

You may obtain directions to the Ritz-CarltonCrowne Plaza Hotel in Atlanta, GAClayton, MO by contacting the Ritz-CarltonCrowne Plaza Hotel at (404) 659-0400314-726-5400 or by accessing their website at http://www.ritzcarlton.com/www.crowneplaza.com/hotels/us/en/Properties/Atlanta/Information/Directions.clayton/stlcm/hotel detail/directions.

VOTING

Who can vote?

All shareholders of record at the close of business on February 28, 201129, 2012 are entitled to vote at the annual meeting.

How many votes can be cast by all shareholders?

At the close of business on February 28, 2011,29, 2012, the record date for voting, we had outstanding 79,674,29280,135,791 shares of common stock. Each shareholder on the record date may cast one vote for each full share owned. The presence in person or by proxy of the holders of a majority of such outstanding shares constitutes a quorum. If a share is present for any purpose at the meeting, it is deemed to be present for the transaction of all business. Abstentions, withheld votes in the election of directors and shares held in street name that are voted on any matter will be included in determining the number of votes present. Shares held in street name that are not voted on any matter at the meeting will not be included in determining whether a quorum is present.

How do I vote?

You may vote either in person at the annual meeting or by proxy. To vote by proxy, you must select one of the following options:

2

2

If you vote in a timely manner by the Internet or telephone, you donot have to return the proxy card for your vote to count. The Internet and telephone voting procedures appear in the upper right of the enclosed proxy card. You may also log on to change your vote or to confirm that your vote has been properly recorded.

If you want to vote in person at the annual meeting, and you own your common stock through a custodian, broker or other agent, you must obtain a proxy from that party in their capacity as owner of record for your shares and bring the proxy to the annual meeting.

Where can I access an electronic copy of the Proxy Statement and Annual Report on Form 10-K for the year ended December 31, 2010?2011?

Important Notice Regarding Availability of Proxy Materials for the Shareholder Meeting to Be Held on April 28, 201126, 2012

You may access an electronic, searchable copy of the Proxy Statement and the Annual Report on Form 10-K for the year ended December 31, 20102011 at http://wfss.mobular.net/wfss/oln.

How are votes counted?

If you specifically mark the proxy card (or vote by telephone or Internet) and indicate how you want your vote to be cast regarding any matter, your directions will be followed. If you sign and submit the proxy card but do not specifically mark it with your instructions as to how you want to vote, the proxy will be voted for the election of the directors named in this proxy statement in Item 1 and for Items 2 and 4 and for a one-year frequency under Item 3 listed in the proxy.

3

Wells Fargo Shareowner Services tabulates the shareholder votes and provides an independent inspector of election as part of its services as our registrar and transfer agent. If you submit a proxy card marked “abstain” or “withhold” on any item other(other than election of directors,directors), your shares will not be voted on

3

the item so marked and your vote will not be included in determining the number of votes cast on that matter. Shares held in street name that are not voted in the election of directors or on Item 2 will not be included in determining the number of votes cast on those matters.

Can I change my vote?

Yes. Whether you vote by Internet or telephone or submit a proxy card with your voting instructions, you may revoke or change your vote by:

When are the votes due?

Proxies submitted by shareholders by Internet or by telephone will be counted in the vote only if they are received by 11:59 p.m. Central Daylight Time on April 27, 2011.25, 2012. Shares represented by proxies on the enclosed proxy card will be counted in the vote at the annual meeting only if wereceive your proxy card by 11:59 p.m. Central Daylight Time on April 27, 2011.25, 2012. Proxies submitted by CEOP participants will be counted in the vote only if they arereceived by 11:59 p.m. Central Daylight Time on April 26, 2011.24, 2012.

How do I vote my shares held in the Olin Contributing Employee Ownership Plan or the Arch Chemicals, Inc. Contributing Employee Ownership Plan?

On February 28, 2011,29, 2012, the Olin Corporation Contributing Employee Ownership Plan (Olin CEOP)CEOP held 4,140,5293,655,654 shares of our common stock and the Arch Chemicals, Inc. Contributing Employee Ownership Plan (Arch CEOP) held 181,842 shares. We sometimes refer to one or both of these plans as the CEOP.stock. ING National Trust serves as the Trustee of the Olin CEOP and JPMorgan Chase Bank serves as Trustee of the Arch CEOP. If you are a participant in eitherthe CEOP, you may instruct the CEOP Trustee of that CEOPon how to vote shares of common stock credited to you on the items of business listed on the proxy card by voting on the Internet or telephone or by indicating your instructions on your proxy card and returning it to us. The TrusteesTrustee will vote shares of common stock held in the CEOP for which they donot receive voting instructions in the same manner proportionately as they vote the shares of common stock for which theydo receive instructions.

How do I vote my shares held in the Automatic Dividend Reinvestment Plan?

Wells Fargo Shareowner Services is our registrar and transfer agent and administers the Automatic Dividend Reinvestment Plan. If you participate in our Automatic Dividend Reinvestment Plan, Wells Fargo Shareowner Services will vote any shares of common stock that it holds for you in accordance with your instructions indicated on the proxy card you return or the vote you make by Internet or telephone. If you do not submit a proxy card for your shares of record or vote by Internet or telephone, Wells Fargo Shareowner Services will not vote your dividend reinvestment shares.

4

MISCELLANEOUS

Can I contact board members directly?

Our audit committee has established the following methods for shareholders or other interested parties to communicate directly with the board and/or its members.

4

The Olin Board or (Name of the director)

c/o Office of the Secretary

Olin Corporation

190 Carondelet Plaza, Suite 1530

Clayton, MO 63105

Who pays for this proxy solicitation?

Olin will pay the entire expense of this proxy solicitation.

Who solicits the proxies and what is the cost of this proxy solicitation?

Our board is soliciting the proxies. We have hired The Proxy Advisory Group, LLC (Proxy Advisory Group), a proxy solicitation firm, to assist us with the distribution of proxy materials and vote solicitation. We will pay Proxy Advisory Group approximately $10,000 for its services and will reimburse Proxy Advisory Group for payments made to brokers and other nominees for their expenses in forwarding proxy solicitation materials.

How will the proxies be solicited?

Proxy Advisory Group will solicit proxies by personal interview, mail, and telephone, and will request brokerage houses and other custodians, brokers and other agents to forward proxy solicitation materials to the beneficial owners of Olin common stock for whom they hold shares. Our directors, officers and employees may also solicit proxies by personal interview and telephone.

How can I submit a shareholder proposal at the 20122013 annual meeting?

If you want to present a proposal to be considered for inclusion in the 20122013 proxy statement for the 20122013 annual meeting, you must deliver the proposal in writing (and include the information required by Olin’s Bylaws) to the Secretary at Olin Corporation, 190 Carondelet Plaza, Suite 1530, Clayton, MO 63105 no later than November 10, 2011.12, 2012. You must then present your proposal in person at the 20122013 annual meeting.

5

If you want to present a proposal for consideration at the 20122013 annual meeting without including your proposal in the proxy statement, you must deliver a written notice (containing the information required by Olin’s Bylaws) to the Secretary at Olin Corporation, 190 Carondelet Plaza, Suite 1530, Clayton, MO 63105 no later than January 27, 2012.26, 2013. You must also present your proposal in person at the 20122013 annual meeting.

5

How can I directly nominate a director for election to the board at the 20122013 annual meeting?

According to Olin’s Bylaws, if you are a shareholder you may directly nominate an individual for election to the board if you deliver a written notice of the nomination to Olin’s Secretary no later than January 27, 2012.26, 2013. Your notice must include:

Although a shareholder may directly nominate an individual for election as a director, the board is not required to include such nominee in the proxy statement.

How can I recommend a director for the slate of candidates to be nominated by Olin’s board for election at the 20122013 annual meeting?

In addition to directly nominating an individual for election to the board as discussed above, you can suggest that our directors and corporate governance committee consider a person for inclusion in the slate of candidates to be proposed by the board for election at the 20122013 annual meeting. You can recommend a person by delivering written notice to Olin’s board no later than October 11, 2011.12, 2012. The notice must include the information described under the heading “What is Olin’s director nomination process?” on page 18, and must be sent to the address indicated under that heading. As noted above, the board is not required to include such nominee in the proxy statement.

How can I obtain shareholder information?

Shareholders may contact Wells Fargo Shareowner Services, our registrar and transfer agent, who also manages our Automatic Dividend Reinvestment Plan at:

Wells Fargo Shareowner Services

PO Box 64874

St. Paul, MN 55164-0874

Telephone: (800) 468-9716

Internet: www.shareowneronline.com, click on “contact us”

Shareholders can sign up for online account access through Wells Fargo Shareowner Services for fast, easy and secure access 24 hours a day, 7 days a week for future proxy materials, investment plan statements, tax documents and more. To sign up log on to www.shareowneronline.com where step-by-step instructions will prompt you through enrollment or you may call (800) 468-9716 for customer service.

6

CERTAIN BENEFICIAL OWNERS

Except as listed below, to our knowledge, no person beneficially owned more than five percent of our common stock as of February 28, 2011.29, 2012.

7

ITEM 1—PROPOSAL FOR THE ELECTION OF DIRECTORS

Who are the individuals nominated by the board to serve as directors?

The board of directors is divided into three classes. Each class has a term of office for three years, and the term of each class ends in a different year. Virginia law and Olin’s Bylaws require that any director elected by the board of directors shall serve only until the earlier of the next election of directors by the shareholders or until his or her successor is elected or until his or her earlier death, resignation or removal. The board has nominated Messrs. Benoist, RompalaBogus, Schulz and RuppSmith as Class IIIII directors with terms expiring in 2014.2015. The board expects that all of the nominees will be able to serve as directors. If any nominee is unable to accept election, a proxy voting in favor of such nominee will be voted for the election of a substitute nominee selected by the board, unless the board reduces the number of directors.

Virginia law and Olin’s Bylaws require that any director elected by the board of directors (rather than the shareholders) shall serve only until the earlier of the next election of directors by the shareholders and until his or her successor is elected or until his or her earlier death, resignation or removal.

The board recommends that you vote FOR the election of Messrs. Benoist, RompalaBogus, Schulz and RuppSmith as Class IIIII directors.

How many votes are required to elect a director?

A nominee will be elected as a director if a majority of the votes cast in the election is in favor of the nominee. Abstentions and sharesShares held in street name that are not voted in the election of directors will not be included in determining the number of votes cast and will not affect the outcome of the vote in the election of directors.

Business Experience of Nominees and Continuing Directors

Set forth below is a description of the business experience of each director nominee and each continuing director, including a discussion of the specific experience, qualifications, attributes and skills that led our board to conclude that those individuals should serve as our directors.

8

CLASS IIIII

NOMINEES FOR THREE-YEAR TERMS EXPIRING IN 20142015

		GRAY G. BENOIST, 58, serves as Senior Vice President, Finance, Chief Financial Officer and Chief Accounting Officer of Belden, Inc. (a designer, manufacturer and marketer of signal transmission solutions, including cable, connectivity and active components for mission-critical applications in markets ranging from industrial automation to data centers, broadcast studios, and aerospace). From August 2006 until February 2009 he served as Vice President, Finance and Chief Financial Officer of Belden, Inc. In February 2009, he assumed the title of Senior Vice President, Finance and Chief Financial Officer of Belden, Inc. and in November 2009 added the title of Chief Accounting Officer. Mr. Benoist was previously Senior Vice President, Director of Finance of the Networks Segment of Motorola Inc. (a business unit responsible for the global design, manufacturing, and distribution of wireless and wired telecom system solutions). During more than 25 years with Motorola, Mr. Benoist served in senior financial and general management roles across Motorola’s portfolio of businesses, including the Personal Communications Sector, Integrated and Electronic Systems Sector, Multimedia Group, Wireless Data Group, and Cellular Infrastructure Group. He has a bachelor’s degree in Finance & Accounting from Southern Illinois University and an MBA degree from the University of Chicago. Olin director since 2009; member of the Audit Committee and the Directors and Corporate Governance Committee. Mr. Benoist’s chief financial officer experience provides him with valuable financial and accounting expertise.
		RICHARD M. ROMPALA, 64, retired in July 2005 from his position as Chairman of The Valspar Corporation (a manufacturer and distributor of paints and coatings). Mr. Rompala served as Chairman of Valspar from 1998 until July 2005, Chief Executive Officer from 1995 through February 2005 and President from 1994 through 2001. Prior to 1994, Mr. Rompala served as Group Vice President-Coatings and Resins for two years and Group Vice President-Chemicals for five years at PPG Industries, Inc. (a manufacturer of coatings, glass and industrial and specialty chemicals). Mr. Rompala holds a bachelor’s degree in chemistry and a bachelor’s degree in chemical engineering from Columbia University and an MBA degree from Harvard Business School. Olin director since 1998; Lead Director, Chair of the Compensation Committee and member of the Audit Committee, Directors and Corporate Governance Committee and the Executive Committee. Mr. Rompala’s broad executive management experience provides him with in-depth knowledge of manufacturing and chemicals companies.

9

		JOSEPH D. RUPP, 60, is Chairman, President and Chief Executive Officer of Olin. He has served as Chairman of Olin since July 2005 and held the positions of President and Chief Executive Officer since January 2002. Prior to that and since March 2001, he was Executive Vice President, Operations, and was responsible for all Olin business operations including the former Brass Division (which became part of the former Metals Group in 2002), Winchester and Chlor Alkali Products. He joined Olin’s Brass Division in 1972 and held a number of positions of increasing responsibility in the Brass Division manufacturing and engineering organization. In 1985, he was appointed Vice President, Manufacturing and Engineering. He was appointed President of Olin Brass and a Corporate Vice President in 1996. He holds a bachelor’s degree in metallurgical engineering from the University of Missouri, Rolla. Mr. Rupp serves on the board of directors of Quanex Building Products Corporation (a manufacturer of value-added engineered materials and components serving building products markets). Olin director since 2002; Chair of the Executive Committee. Mr. Rupp’s extensive history at Olin, together with his board service at other companies, provides him with in-depth knowledge of Olin’s business and the industry.

The terms of the following directors will continue after the 20112012 annual meeting, as indicated below.

CLASS I

DIRECTORS WHOSE TERMS CONTINUE UNTIL 2013

		C. ROBERT BUNCH, 56, is Chairman of the Board and Chief Executive Officer of Global Tubing, LLC (a privately held company formed in April 2007 to manufacture and sell coiled tubing and related products and services to the energy industry), a position he has held since May 2007. Mr. Bunch served as Chairman of Maverick Tube Corporation (a producer of welded tubular steel products used in energy and industrial applications which was acquired by Tenaris, S.A. in October 2006) from January 2005 until October 2006 and as President and Chief Executive Officer from October 2004 until October 2006. Prior to joining Maverick, he was an independent oil service consultant from 2003 until 2004, and from 2002 to 2003 he served as President and Chief Operating Officer at Input/Output, Inc. (an independent provider of seismic imaging technologies and digital, full-wave imaging solutions for the oil and gas industry). From 1999 to 2002, he served as Vice President and Chief Administrative Officer of Input/Output, Inc. Mr. Bunch earned a bachelor’s degree in economics and a master’s degree in accounting from Rice University and a juris doctorate degree from the University of Houston. In addition to serving on the board of Global Tubing, LLC, he is Chairman of the board of directors of Sub-One Technology, Inc. (a privately held company with proprietary technology for depositing hard, smooth, pure coatings on the internal surfaces of a broad spectrum of products) and a member of the board of directors of Smith InnerArmor Technologies (an affiliate of Sub-One Technology, Inc.). From May 2004 until August 2008, Mr. Bunch served on the board of directors (and as Chairman from January 2007 to August 2008) of Pioneer Drilling Company (a provider of land contract drilling services to independent and major oil and gas exploration and production companies). Olin director since 2005; member of the Compensation Committee and the Directors and Corporate Governance Committee. Mr. Bunch’s broad management responsibilities provide relevant experience in a number of strategic and operational areas.

10

		RANDALL W. LARRIMORE, 63, served as the Chairman of Olin from April 2003 through June 2005. From 1997 until his retirement in December 2002, he served as President and Chief Executive Officer of United Stationers Inc. (a $4 billion wholesaler/distributor of office products). From 1988 until 1997, he was President and Chief Executive Officer of MasterBrand Industries, Inc., a subsidiary of Fortune Brands, Inc. (a consumer products company). He holds a bachelor’s degree from Swarthmore College where he was trained as a chemist and an MBA degree from Harvard Business School. He is co-chair of the governance committee and a member of the board of directors and audit committee of Campbell Soup Company (a manufacturer and marketer of soup and other food products) and a member of the board of directors of Nixon Uniform Service and Medical Wear (a privately held company that provides, launders, and delivers medical apparel, linens, and other reusable products, primarily to healthcare providers). Olin director since 1998; Chair of the Directors and Corporate Governance Committee and a member of the Audit Committee, Compensation Committee and the Executive Committee. Mr. Larrimore brings expertise in marketing, sales, strategic planning and general management, as well as substantial experience in mergers and acquisitions.

		JOHN M. B. O’CONNOR, 56, is Chairman and Chief Executive Officer of Tactronics Holdings, LLC (a privately held company that provides tactical integrated electronic systems to the military, civil service, Homeland Security and manufacturing markets). He also serves as Chairman of J.H. Whitney Investment Management, LLC (a firm which specializes in Asian Markets investment strategies), a position he has held since January 2009, and on the board of managers of JHW Pan Asia Strategies Fund, LLC, a registered investment company. From June 2004 to January 2009, he served as Chief Executive Officer of J.H. Whitney Investment Management, LLC. Previously, Mr. O’Connor was Chairman of JP Morgan Alternative Asset Management, Inc. (part of the investment manager arm of JP Morgan), Chairman of JP Morgan Incubator Strategies, Inc. (a hedge fund investment arm of JP Morgan) and an Executive Partner of JP Morgan Partners (a private equity firm) and responsible for all proprietary and client Hedge Fund and Fund of Fund activities of JP Morgan, in addition to his responsibilities as a Senior Private Equity Manager. He was also a member of the Risk Management Committee of JP Morgan Chase, which is responsible for policy formulation and oversight of all market and credit risk taking activities globally. Mr. O’Connor earned a bachelor’s degree in economics from Tulane University and an MBA degree from Columbia University Graduate School of Business. Mr. O’Connor serves as a Director of the Fund for Public Health in the City of New York (a public-private partnership which manages the City’s healthcare preparedness for bioterrorism threats) and is a trustee of the China Institute (the oldest institution in America focused on the U.S.-China relationship). Mr. O’Connor also serves on the boards of the Fund for the City of New York (an organization which develops and helps implement innovations in policy, programs, practices and technology in order to advance the functioning of government and nonprofit organizations) and The Animal Care and Control Center in the City of New York as well as North Carolina Outward Bound. Mr. O’Connor serves in a pro-bono capacity for the U.S. Department of Defense. He is a member of the Command Advisory Group of both the United States European Command and the United States Southern Command and a member of the Highland Forum which supports the Under

11

CLASS III

DIRECTORS WHOSE TERMS CONTINUE UNTIL 2012

		DONALD W. BOGUS, 64,65, retired in January 2009 from his position as Senior Vice President of The Lubrizol Corporation and President of Lubrizol Advanced Materials, Inc., a wholly-owned subsidiary of The Lubrizol Corporation (a global supplier of high performance specialty products for personal care, coatings, plastics, and various industrial products), a position he had held since June 2004. Mr. Bogus joined Lubrizol in April 2000 as Vice President and his duties included responsibility for the Fluid Technologies for Industry business section and he served as the head of mergers and acquisitions. Prior to joining Lubrizol, he was an Executive Officer at PPG Industries, Inc. (a manufacturer of coatings, glass and industrial and specialty chemicals) where he served as Vice President of Specialty Chemicals and Vice President of Industrial Coatings. Mr. Bogus earned a bachelor’s degree in biology and chemistry from Baldwin Wallace College. He serves on the Board of Trustees for Baldwin Wallace College and on their Business Division’s Business Advisory Board. Olin director since 2005; member of the Compensation Committee and the Directors and Corporate Governance Committee. Mr. Bogus’ executive management positions have provided him with expertise in the chemicals industry, as well as merger and acquisition experience.

		PHILIP J. SCHULZ, 66,67, was Managing Partner of PricewaterhouseCoopers (a registered public accounting firm) Hartford, Connecticut office until his retirement in July 2003. Mr. Schulz also served as the Hartford office leader of PwC’s Consumer & Industrial Products & Services industry group. He joined Coopers & Lybrand in 1967 and was Managing Partner of the Hartford office at the time of the merger of Coopers & Lybrand and Price Waterhouse in 1998. He was a member of the Firm Council and was a trustee of the PwC Foundation. He also served as a regional technical consultant and SEC reviewer and was assigned to the firm’s national office for two years. Olin’s board of directors has determined that Mr. Schulz qualifies as an “audit committee financial expert” for Olin under applicable SEC rules. Mr. Schulz earned a bachelor’s degree in accounting from Niagara University and also completed the Tuck Executive Program at Dartmouth College. He is a director and audit committee chair of The Connecticut Bank & Trust Company (a state banking institution). Mr. Schulz is also trustee emeritus of St. Joseph College; a director of St. Francis Hospital; a director of the Lake Sunapee Protective Association and is on the board of trustees of The McLean Fund. Olin director since 2003; Chair of the Audit Committee and a member of the Directors and Corporate Governance Committee and the Executive Committee. Mr. Schulz’s public accounting background provides him with invaluable financial and accounting expertise.

129

		VINCENT J. SMITH, 61,62, served as President and Chief Executive Officer of Dow Chemical Canada, a subsidiary of The Dow Chemical Co. (a diversified chemical manufacturing company) from 2001 until his retirement in 2004. From 1972 to 2000, he held positions of increasing responsibility in engineering, manufacturing and management, including the position of Business Director for Dow’s global chlor alkali assets. Mr. Smith earned a bachelor’s degree in chemical engineering from McMaster University. He is a member and is Co-Chairman of the board of directors of Climate Change Central (a not-for-profit organization that brings private and public sector leaders together to find an effective way to manage climate change challenges in the province of Alberta, Canada). Olin director since 2008; member of the Compensation Committee and the Directors and Corporate Governance Committee. Mr. Smith’s executive service has provided him with valuable international and manufacturing experience, together with extensive knowledge of the Chlor Alkali industry.

CLASS I

DIRECTORS WHOSE TERMS CONTINUE UNTIL 2013

		C. ROBERT BUNCH, 57, is Chairman of the Board and Chief Executive Officer of Global Tubing, LLC (a privately held company formed in April 2007 to manufacture and sell coiled tubing and related products and services to the energy industry), a position he has held since May 2007. Mr. Bunch served as Chairman of Maverick Tube Corporation (a producer of welded tubular steel products used in energy and industrial applications which was acquired by Tenaris, S.A. in October 2006) from January 2005 until October 2006 and as President and Chief Executive Officer from October 2004 until October 2006. Prior to joining Maverick, he was an independent oil service consultant from 2003 until 2004, and from 2002 to 2003 he served as President and Chief Operating Officer at Input/Output, Inc. (an independent provider of seismic imaging technologies and digital, full-wave imaging solutions for the oil and gas industry). From 1999 to 2002, he served as Vice President and Chief Administrative Officer of Input/Output, Inc. Mr. Bunch earned a bachelor’s degree in economics and a master’s degree in accounting from Rice University and a juris doctorate degree from the University of Houston. From May 2004 until August 2008, Mr. Bunch served on the board of directors (and as Chairman from January 2007 to August 2008) of Pioneer Drilling Company (a provider of land contract drilling services to independent and major oil and gas exploration and production companies). Olin director since 2005; member of the Compensation Committee and the Directors and Corporate Governance Committee. Mr. Bunch’s broad management responsibilities provide relevant experience in a number of strategic and operational areas.
		RANDALL W. LARRIMORE, 64, served as the Chairman of Olin from April 2003 through June 2005. From 1997 until his retirement in December 2002, he served as President and Chief Executive Officer of United Stationers Inc. (a $4 billion wholesaler/distributor of office products). From 1988 until 1997, he was President and Chief Executive Officer of MasterBrand Industries, Inc., now called Fortune Brands Home & Security LLC (FBHS) (a consumer products company). He holds a bachelor’s degree from Swarthmore College where he was trained as a chemist and an MBA degree from Harvard Business School. He is co-chair of the governance committee and a member of the board of

10

		directors and compensation committee of Campbell Soup Company (a manufacturer and marketer of soup and other food products) and a member of the board of directors of Nixon Uniform Service and Medical Wear (a privately held company that provides, launders, and delivers medical apparel, linens, and other reusable products, primarily to healthcare providers). Olin director since 1998; Chair of the Directors and Corporate Governance Committee and a member of the Audit Committee, Compensation Committee and the Executive Committee. Mr. Larrimore brings expertise in marketing, sales, strategic planning and general management, as well as substantial experience in mergers and acquisitions.
		JOHN M. B. O’CONNOR, 57, is Chairman of J.H. Whitney Investment Management, LLC (a firm which specializes in Asian Markets investment strategies), a position he has held since January 2005, and on the board of managers of JHW Pan Asia Strategies Fund, LLC, a registered investment company. From January 2009 through March 2011, he served as Chief Executive Officer of Tactronics Holdings, LLC (a privately held company that provides tactical integrated electronic systems to the military, civil service, Homeland Security and manufacturing markets). Previously, Mr. O’Connor was Chairman of JP Morgan Alternative Asset Management, Inc. (part of the investment manager arm of JP Morgan), Chairman of JP Morgan Incubator Strategies, Inc. (a hedge fund investment arm of JP Morgan) and an Executive Partner of JP Morgan Partners (a private equity firm) and responsible for all proprietary and client Hedge Fund and Fund of Fund activities of JP Morgan, in addition to his responsibilities as a Senior Private Equity Manager. He was also a member of the Risk Management Committee of JP Morgan Chase, which is responsible for policy formulation and oversight of all market and credit risk taking activities globally. Mr. O’Connor earned a bachelor’s degree in economics from Tulane University and an MBA degree from Columbia University Graduate School of Business. Mr. O’Connor serves as a special consultant in a pro-bono capacity for the U.S. Department of Defense and is an appointed special consultant to the Department of Defense Business Board. He is a member of the Senior Advisors Panel of both the United States European Command and the United States Southern Command and a member of the Highland Forum which supports the Under Secretary of Defense for Intelligence. Mr. O’Connor also serves on the boards of the Fund for the City of New York (an organization which develops and helps implement innovations in policy, programs, practices and technology in order to advance the functioning of government and nonprofit organizations) and The Animal Care and Control Center in the City of New York as well as North Carolina Outward Bound. He is a trustee of the China Institute (the oldest institution in America focused on the U.S.—China relationship). Olin director since 2006; member of the Audit Committee and the Directors and Corporate Governance Committee. Mr. O’Connor’s hedge fund and investment banking experience allow him to contribute broad financial and global expertise.

11

CLASS II

DIRECTORS WHOSE TERMS CONTINUE UNTIL 2014

		GRAY G. BENOIST, 59, resigned on January 1, 2012 from his position as Senior Vice President, Finance, Chief Financial Officer and Chief Accounting Officer of Belden, Inc. (a designer, manufacturer and marketer of signal transmission solutions, including cable, connectivity and active components for mission-critical applications in markets ranging from industrial automation to data centers, broadcast studios, and aerospace) in anticipation of his retirement. From January 1 through March 4, 2012, he served as an Officer on Special Assignment at Belden and retired on March 15, 2012. From August 2006 until January 1, 2012 he served as Senior Vice President, Finance and Chief Financial Officer of Belden and from November 2009 until January 2012 he also served as Chief Accounting Officer. Prior to that, Mr. Benoist was Senior Vice President, Director of Finance of the Networks Segment of Motorola Inc. (a business unit responsible for the global design, manufacturing, and distribution of wireless and wired telecom system solutions). During more than 25 years with Motorola, Mr. Benoist served in senior financial and general management roles across Motorola’s portfolio of businesses, including the Personal Communications Sector, Integrated and Electronic Systems Sector, Multimedia Group, Wireless Data Group, and Cellular Infrastructure Group. He has a bachelor’s degree in Finance & Accounting from Southern Illinois University and an MBA degree from the University of Chicago. Olin director since 2009; member of the Audit Committee and the Directors and Corporate Governance Committee. Mr. Benoist’s chief financial officer experience provides him with valuable financial and accounting expertise.
		RICHARD M. ROMPALA, 65, retired in July 2005 from his position as Chairman of The Valspar Corporation (a manufacturer and distributor of paints and coatings). Mr. Rompala served as Chairman of Valspar from 1998 until July 2005, Chief Executive Officer from 1995 through February 2005 and President from 1994 through 2001. Prior to 1994, Mr. Rompala served as Group Vice President-Coatings and Resins for two years and Group Vice President-Chemicals for five years at PPG Industries, Inc. (a manufacturer of coatings, glass and industrial and specialty chemicals). Mr. Rompala holds a bachelor’s degree in chemistry and a bachelor’s degree in chemical engineering from Columbia University and an MBA degree from Harvard Business School. Olin director since 1998; Lead Director, Chair of the Compensation Committee and member of the Audit Committee, Directors and Corporate Governance Committee and the Executive Committee. Mr. Rompala’s broad executive management experience provides him with in-depth knowledge of manufacturing and chemicals companies.

12

		JOSEPH D. RUPP, 61, is Chairman, President and Chief Executive Officer of Olin. He has served as Chairman of Olin since July 2005 and held the positions of President and Chief Executive Officer since January 2002. Prior to that and since March 2001, he was Executive Vice President, Operations, and was responsible for all Olin business operations including the former Brass Division (which became part of the former Metals Group in 2002), Winchester and Chlor Alkali Products. He joined Olin’s Brass Division in 1972 and held a number of positions of increasing responsibility in the Brass Division manufacturing and engineering organization. In 1985, he was appointed Vice President, Manufacturing and Engineering. He was appointed President of Olin Brass and a Corporate Vice President in 1996. He holds a bachelor’s degree in metallurgical engineering from the University of Missouri, Rolla. Mr. Rupp serves on the board of directors of Quanex Building Products Corporation (a manufacturer of value-added engineered materials and components serving building products markets). Olin director since 2002; Chair of the Executive Committee. Mr. Rupp’s extensive history at Olin, together with his board service at other companies, provides him with in-depth knowledge of Olin’s business and the industry.

13

CORPORATE GOVERNANCE MATTERS

How many meetings did board members attend?

During 2010,2011, the board held nineten meetings. As part of each regularly scheduled board meeting, the non-executive directors met in executive session. All directors attended at least 75% of the meetings of the board and committees of the board on which they served. All of our directors attended the 20102011 annual shareholders meeting, except Mr. Schulz who was unable to attend as the result of last minute weather-related flight cancellations.meeting. Our policy regarding directors’ attendance at the annual shareholders meeting is that they are required to attend, absent serious extenuating circumstances.

Which board members are independent?

Our board has determined that all of its members, except Mr. Rupp, are independent in accordance with applicable New York Stock Exchange (NYSE) listing standards and applicable provisions of our Principles of Corporate Governance. In determining independence, the board confirms that a director has no relationship with Olin that violates the “bright line” independence standards under the NYSE listing standards. The board also reviews whether a director has any other material relationship with Olin, after consideration of all relevant facts and circumstances. In assessing the materiality of a director’s relationship to Olin, the board considers the issues from the director’s standpoint and from the perspective of the persons or organizations with which the director has an affiliation. The board reviews commercial, industrial, banking, consulting, legal, accounting, charitable and familial relationships.

In 2009, our board of directors adopted a bright line test for the types of de minimis transactions that do not warrant board consideration when making director independence determinations. This policy provides that any transaction or series of transactions between Olin (or its subsidiaries) and a director (or an organization in which he/she serves as a director, partner, shareholder or officer) does not impair that director’s independence if the transactions are for the purchase or sale of products or services that (i) involve less than $50,000 in the aggregate in any 12-month period and (ii) have the same pricing and other terms and conditions as transactions with unrelated and similarly situated customers or suppliers. Accordingly, in making its determination of director independence, the board did not consider transactions that fell within these parameters.

During 2010, a gun club of which2011, one of our directors, John M. B. O’Connor, purchased approximately $6,145 of ammunition from Olin and a gun club of which Mr. O’Connor is a member and director, purchased approximately $91,000$73,350 of ammunition from Olin. Our board determined that these transactions did not impair Mr. O’Connor’s independence because the total amount involved was not significant to Olin and the purchases were on our customary terms and conditions for unrelated third parties. Although Mr. O’Connor serves as an appointee on the Command Advisory Groups, as a member of the Highland Forum and as an appointed special consultant to the Defense Business Board (as noted in his biographical information above), the board did not consider sales of ammunition by our Winchester Division to the service branches of the Department of Defense to be relevant to determining Mr. O’Connor’s independence, given the nature of Mr. O’Connor’s service and the fact that the Command Advisory Groups, the Highland Forum and Defense Business Board have no involvement in sourcing materials.

In 2010,2011, we matched charitable contributions made by severalsome directors under our 50% matching contribution program, which is available to all employees. None of those amounts exceeded $5,000 and our board determined that such minimal charitable contribution matches do not constitute the type of relationship that could impair a director’s independence.

Does Olin have corporate governance guidelines and a code of conduct?

The board has adopted Principles of Corporate Governance and a Code of Conduct. The Code of Conduct applies to our directors and all of our employees, including our chief executive officer, chief

14

financial officer, and principal accounting officer/controller. We discuss certain provisions of these documents in more detail below under the heading “Review, Approval or Ratification of Transactions with Related Persons.”

Each of our three major standing board committees (Audit, Compensation and Directors and Corporate Governance) acts under a written charter adopted by the board. All of these documents can be viewed on our website at www.olin.com in the Governance section under Governance Documents and Committees. In addition, we will disclose on that website we will disclose any amendment to, or waiver from, a provision of our Code of Conduct for our directors and executive officers, including our chief executive officer, chief financial officer, principal accounting officer/controller or other employees performing similar functions.

Do Olin’s board and committees conduct evaluations?

As required by NYSE rules, Olin’s board of directors as well as its Audit, Compensation and Directors and Corporate Governance Committees each conduct an annual performance evaluation.

What are the committees of the board?

Our committees of the board are:

TheAudit Committee, which held eightsix meetings during 2010,2011, advises the board on internal and external audit matters affecting us. The audit committee acts under a written charter adopted by the board in 1997, and reviewed and updated in 2011. In accordance with NYSE listing standards and applicable provisions of our Principles of Corporate Governance, the audit committee is comprised solely of directors who meet the enhanced independence standards for audit committee members under the Securities Exchange Act of 1934 (Exchange Act) and the related rules as incorporated into the NYSE standard for independence. Its members are: Philip J. Schulz, Chair, Gray G. Benoist, Randall W. Larrimore, John M. B. O’Connor and Richard M. Rompala. The board has determined that Philip J. Schulz meets the SEC definition of an “audit committee financial expert” and that each of the members of the audit committee is financially literate, as such term is interpreted by the board in its business judgment. The audit committee:

15

TheCompensation Committee, which held sixseven meetings during 2010,2011, sets policy, develops and monitors strategies for, and administers, the programs that are used to compensate the chief executive officer and other senior executives. In accordance with NYSE listing standards and applicable provisions of our Principles of Corporate Governance, the compensation committee is comprised solely of directors who meet the NYSE standard for independence. Its members are: Richard M. Rompala, Chair, Donald W. Bogus, C. Robert Bunch, Randall W. Larrimore and Vincent J. Smith. The compensation committee:

The compensation committee is authorized to delegate certain responsibilities to internal and independent accountants, internal and outside lawyers and other internal staff to the extent permitted by applicable law.

16

TheDirectors and Corporate Governance Committee, which held threefour meetings during 2010,2011, assists the board in fulfilling its responsibility to our shareholders relating to the selection and nomination of officers and directors. In accordance with NYSE listing standards and applicable provisions of our Principles of Corporate Governance, the directors and corporate governance committee is comprised solely of directors who meet the NYSE standard for independence. Its

16

members are: Randall W. Larrimore, Chair, Gray G. Benoist, Donald W. Bogus, C. Robert Bunch, John M. B. O’Connor, Richard M. Rompala, Philip J. Schulz and Vincent J. Smith. The directors and corporate governance committee:

TheExecutive Committee meets as needed in accordance with our Bylaws. Between meetings of the board, the executive committee may exercise all the power and authority of the board (including authority and power over our financial affairs) except for matters reserved to the full board by Virginia law and matters for which the board gives specific directions. During 2010,2011, this committee held no meetings. The executive committee members are: Joseph D. Rupp, Chair, Randall W. Larrimore, Richard M. Rompala and Philip J. Schulz.

Compensation Committee Interlocks and Insider Participation

No member of our compensation committee during 20102011 (Messrs. Bogus, Bunch, Larrimore, Rompala and Smith):

17

None of our executive officers:

17

What is Olin’s director nomination process?

Our directors and corporate governance committee acts as our nominating committee. As a policy, the committee considers any director candidates suggested by shareholders if we receive the appropriate information in a timely manner. Our Principles of Corporate Governance provide that the board chair and CEO, lead director, other directors, employees and shareholders may recommend director nominees to the committee. The committee uses the same process to review and evaluate all potential director nominees, regardless of who recommends the candidate. The committee reviews and evaluates each nominee and the committee chair, the board chair and CEO and lead director interview the potential new board candidates selected by the committee. The interview results, along with the committee’s recommended nominees, are submitted to the full board.

Our Principles of Corporate Governance describe criteria for new board members to include recognized achievement plus skills such as a special understanding or ability to contribute to some aspect of Olin’s business. The committee is tasked with seeking board members with the personal qualities and experience that taken together will ensure a strong board of directors. Although we have no formal policy on diversity for board members, our Principles of Corporate Governance provide that racial and gender diversity are important factors in assessing potential board members, but not at the expense of particular qualifications and experience required to meet the needs of the board. Furthermore, as part of the committee’s review of board composition, the board considers diversity of experience and background in an effort to ensure that the composition of our directors ensures a strong and effective board. Our Principles of Corporate Governance cite strength of character, an inquiring and independent mind, practical wisdom, and mature judgment as among the principal qualities of an effective director.

This year, we have three nominees standing for re-election.

A shareholder can suggest a person for nomination as a director by providing the name and address of the candidate, and a detailed description of his or her experience and other qualifications for the position, in writing addressed to the board of directors in care of the Secretary, Olin Corporation, 190 Carondelet Plaza, Suite 1530, Clayton, MO 63105. The notice may be sent at any time, but for a candidate to be considered by the committee as a nominee for an annual shareholder meeting, we must receive the written information at least 150 days before the anniversary of the date of the prior year’s proxy statement. For example, for candidates to be considered for nomination by the committee at the 20122013 annual meeting, we must receive the information from shareholders on or before October 11, 2011.12, 2012.

In addition to shareholders proposing candidates for consideration by the committee, Olin’s Bylaws allow shareholders to directly nominate individuals at the annual shareholder meeting for election to the board by delivering a written notice as described under the heading “How can I directly nominate a director for election to the board at the 20122013 meeting?” on page 6 under the heading “Miscellaneous” above. Although a shareholder may directly nominate an individual for election as a director, the board is not required to include such nominee in the proxy statement.

18

What is your board leadership structure?

Our Principles of Corporate Governance state that our board may select either a combined CEO board chair coupled with a lead director or appoint a board chair who does not also serve as CEO. Currently, our CEO also serves as chairman of the board, and the board selects a separate independent lead director.

The board believes that this leadership structure is best for Olin at the current time, as it appropriately balances the need for the CEO to run the company on a day-to-day basis with significant

18

involvement and authority vested in an outside independent board member—the lead director. The role of our lead director is fundamental to our decision to combine the CEO and board chair positions. Our lead director assumes many functions traditionally within the purview of a chairman of the board. Under our Principles of Corporate Governance, our lead director must be independent, and is responsible for:

How does your board oversee Olin’s risk management process?

Our board is responsible for oversight of Olin’s risk assessment and management process. The board delegated to the compensation committee basic responsibility for oversight of management’s compensation risk assessment, and that committee reports to the board on its review. Our board also delegated tasks related to risk process oversight to our audit committee, which reports the results of its review process to the board. The audit committee’s process includes:

In addition to the reports from the audit and compensation committees, our board periodically discusses risk oversight, including as part of its annual detailed corporate strategy review.

Frank M. O’Brien, Vice President, Internal Audit, reports directly to our audit committee and has direct and unrestricted access to that committee. John E. Fischer,Todd A. Slater, our Senior Vice President, Finance and Chief Financial Officer,Controller, oversees our ERM process and fulfills the responsibilities of a chief risk officer. Mr. FischerSlater reports to the Chairman,our Senior Vice President and CEO of the Corporation,Chief Financial Officer, but has direct access to our audit committee chair. Messrs. FischerSlater and O’Brien, individually or with other members of our management team, periodically meet in executive session with the audit committee.

19

Report of the Audit Committee

The audit committee’s primary responsibility is to assist the board in its oversight of the integrity of the Corporation’s financial reporting process and systems of internal control, to evaluate the independence and performance of the Corporation’s independent registered public accounting firm, KPMG LLP, and internal audit functions and to encourage private communication between the audit committee and KPMG and the internal auditors.

The committee held eightsix meetings during the year. During the second half of 2010,2011, the audit committee also completed a self-assessment.

In discharging its responsibility, the audit committee reviewed and discussed the audited financial statements for fiscal year 20102011 with management and KPMG, including the matters required to be discussed by Statement on Auditing Standards (SAS) No. 61, Communication with Audit Committees, as amended (AICPA, AU Section 380), as adopted by the Public Company Accounting Oversight Board (PCAOB) in Rule 3200T.

In addition, the audit committee has received the written disclosures and the letter from KPMG required by applicable requirements of the PCAOB regarding KPMG’s communications with the audit committee concerning independence. The audit committee discussed with KPMG the issue of its independence from Olin and reviewed KPMG’s reports on the firm’s quality review procedures and findings, results of peer reviews and investigations and inquiries, including corrective actions taken. The audit committee also negotiated the hiring of KPMG for the 20102011 audit and pre-approved all fees which SEC rules require the committee to approve to ensure that the work performed was permissible under applicable standards and would not impair KPMG’s independence.

Based on the audit committee’s discussions with management and KPMG and the audit committee’s review of KPMG’s written report and the other materials discussed above, the audit committee recommended that the board of directors include the audited consolidated financial statements in Olin’s Annual Report on Form 10-K for the year ended December 31, 2010,2011, to be filed with the SEC.

February 17, 201116, 2012

Philip J. Schulz, Chair

Gray G. Benoist

Randall W. Larrimore

John M. B. O’Connor

Richard M. Rompala

20

SECURITY OWNERSHIP OF DIRECTORS AND OFFICERS

How much stock is beneficially owned by each director, director nominee and by the named executive officers in the Summary Compensation Table?

This table shows how many shares of our common stock certain persons beneficially owned on January 15, 2011.2012. Those persons include each director, director nominee, each named executive officer (NEO) in the Summary Compensation Table on page 33,36, and all directors and executive officers as a group. A person has “beneficial ownership” of shares if the person has voting or investment power over the shares or the right to acquire such power within 60 days. “Investment power” means the power to direct the sale or other disposition of the shares. Each person has sole voting and investment power over the number of shares listed, except as noted in the following table.

21

Review, Approval or Ratification of Transactions with Related Persons

Our Principles of Corporate Governance and our Code of Conduct include policies and procedures requiring pre-approval of certain transactions involving our directors and employees and their family members and affiliated organizations if Olin is a direct or indirect participant. The policies define “family member” to mean a spouse, child, sibling, stepchild, parent, stepparent, mother-, father-, son-, daughter-, brother- or sister- in-law, or any other person living with the individual (except tenants and household employees). Affiliated organizations include those entities where the individual or family member serves as a director, executive officer or holder of 5%five percent or more of the equity interests.

Our Principles of Corporate Governance require the directors and corporate governance committee (or, if that committee determines it is appropriate, the board) to pre-approve the following transactions with directors, family members and affiliated organizations:

Our Principles of Corporate Governance require our directors and corporate governance committee to pre-approve service by any senior executive (our CEO and other Section 16 officers) on the board of another public company or on the board of any private company that would represent a material commitment of time. In addition, our Code of Conduct and related Corporate Policy Statement require the approval of the board of directors before an officer may serve as a director or provide services to another organization (as an officer, employee, consultant, etc.). Any such service by other employees must be pre-approved by our President and CEO, if the potential for a conflict of interest exists. These provisions also prohibit any employee or family member from having any direct or indirect interest in, or any involvement with or obligation to, any business organization (including any non-profit entity to which Olin makes contributions) which does or seeks to do business with Olin, or any Olin competitor, without pre-approval from the employee’s department head.

In granting pre-approval, the directors and corporate governance committee, board members and management focus on the best interests of Olin.

In addition to the pre-approval process described above, our Code of Conduct and related Corporate Policy Statements prohibit any director or employee from engaging in a transaction that might conflict with the best interests of Olin.

Section 16(a) Beneficial Ownership Reporting Compliance

Section 16(a) of the Exchange Act requires our officers and directors, and persons who beneficially own more than ten percent of our common stock, to file reports of ownership and changes in ownership with the SEC, and these persons must furnish us with copies of the forms they file. Officers, directors and ten-percent beneficial owners complied with all Section 16(a) filing requirements in 2010.2011.

22

COMPENSATION DISCUSSION AND ANALYSIS

Compensation ObjectivesExecutive Summary

We designOur compensation committee reviews and oversees our executive compensation policies and programs to ensure they enhance our ability to attract, motivate and retain the highest quality executives, with a focus onand maximize attention to shareholder return. Our goal is to compete in the market for people with the talentannual and skills we believe necessary to our success. We construct ourlong-term executive compensation programprograms are designed so that payment of awards is contingent on performance results and its various componentsthey are constructed to reflect market practices. Several componentsIn tying most of executiveour executives’ pay to company results, our compensation vary with our results toprograms (i) align our executives’ interests with those of our shareholders and provide a motivational element. We also design(ii) induce our program to provide an incentive to executivesmanagement team to achieve other strategic objectives consistent with our most important goals.

The following chart identifies the extent to which our executives’ total pay opportunities are variable with results. It illustrates the strong emphasis we place on short- and long-term incentives for our named executive officers (NEOs):

The data in the following table illustrate information the committee considered at the start of 2011 when it set compensation opportunities for that year, and reflect the alignment between our performance and the pay opportunities for our Chief Executive Officer. The percentiles in the table show each compensation element for the CEO and Olin’s performance relative to those of the 61 materials companies included in the S&P 1000 plus selected direct competitors* (which we refer to as the “Performance Share Comparison Group”). Based on this analysis, the committee believes the alignment of our CEO’s total direct compensation opportunity with Olin’s performance is responsive to our shareholders’ interests.

23

Three-Year Financial Performance Relative to Performance Share Comparison Group

Fiscal 2008-2010

  Salary = base salary.

  Target Total Cash = target total cash compensation (salary and target annual incentive payment).

  Target TDC = target total direct compensation (salary, target annual incentive payment and target equity awards).

  TSR = trailing three-year total shareholder return.

  ROC = return on capital.

Over the past three years, the committee took the following actions that illustrate its commitment to ensure our executive compensation programs remain appropriately responsive to emerging market place practices:

These committee actions and other decisions illustrate some of the ways we have increased the link between executive pay and company performance, while maintaining consistency in our executive compensation programs, which are described in detail in the following pages.

24

General Executive Compensation Process

Our compensation committee consists of directors determined to be independent under the NYSE listing criteria. The committee establishes total compensation opportunities (and each of the individual elements) for Joseph D. Rupp, Chairman, President and Chief Executive Officer (the CEO). The committee also approves compensation offor the other named executive officers (NEOs)NEOs based on recommendations by the CEO.CEO, once an individual is identified as an NEO.

To assist it in performing its duties, the committee engages Exequity LLP, an independent board and management advisory firm. Exequity does no other work for Olin and so provides the committee with independent advice. In the past several years, the committee discussed its compensation philosophy with Exequity, but otherwise did not impose any specific limitations or constraints on, or otherwise direct, the manner in which Exequity performed its advisory services.

As advisor to the compensation committee, Exequity reviewed the total compensation strategy and pay levels for our NEOs, examined all aspects of our executive compensation programs to ensure their ongoing support of our business strategy, informed the committee of developing legal and regulatory considerations affecting executive compensation and benefit programs, and provided general advice to the committee on all compensation decisions pertaining to the CEO and to all senior executive compensation recommendations submitted by management. The committee routinely meets in executive session (without the CEO or other officers present). As appropriate, Exequity attends some of those executive sessions. In addition to the committee’s retention of Exequity, Olin periodically retains one or more other compensation consulting firms to provide general services, such as actuarial services for pension plans.

At last year’s annual meeting of our shareholders, we held an advisory vote on executive compensation. Approximately 90% of the shares voted were cast in support of our 2010 executive compensation and related disclosures. The committee viewed the results of this vote as general broad shareholder support for our executive compensation program. Accordingly, we made no changes to our executive compensation program as a result of that vote.

Benchmarking

OurIn designing and implementing our executive compensation consultant provides significant market data toprograms, the committee including an annual assessment of our relative positionreviews competitive data from the Aon Hewitt Total Compensation DataBase^TM (the “DataBase”). These data represent pay practices among a group of over 250 general350 manufacturing and services companies that we have used for benchmarking in the pastfor several years, including 2010.years. This group of companies consists ofcomprises the entire community of manufacturing and services companies that participate in the Hewitt Associates Total Compensation DataBase™ (the DataBase),DataBase, excluding companies that operate in energy services, retail, health services and financial sectors. Our committee reviews revenue-adjusted data from this cross-section of companies. We sometimes refer to this revenue-adjusted groupthese companies as the “comparator group.” Our reliance onThe committee’s review of pay practices amongacross a community as large and varied as the comparator group reflects the committee’s belief that our labor market for executive talent extends beyond the limited group of chemical and ammunition companies and spans all of the relevant manufacturing and services community. The committee believes that the comparator group is a good representation of that labor pool, as the DataBase is a widely respected source of

23

executive compensation information. Our decision to rely on it for competitive pay information ensures that a reputable and unrelated organization actively secures and analyzes the compensation data on which our committee bases its judgment about appropriate levels of pay for our executive officers.

The data relied uponreviewed by the committee wereare adjusted for size (revenues) to reflect compensation being paid at companies of comparable scope to Olin. The data benchmark the committee used to base its annual pay decisions was a statistical summary of the pay practices for the companies in the comparator group, and werewas not representative of any individual company. In fact, the committee does

25

not know the identity of the companies whose pay practices are reflected in the DataBase, nor does it receive information with respect to pay practices at any individual company included in the DataBase. Instead, the committee considered the median pay levels in the comparator group after adjusting the pay practices for an observable relationship between executive pay levels and company size and relied on those statistical representations as typifying revenue-adjusted general industry norms. It was against these norms that the committee drew its conclusions about the appropriateness of the overall executive officer pay levels. Throughout this Compensation Discussion and Analysis, references to “competitive data” or “market” mean this statistical summarized data for the comparator group.

Elements of Compensation

Overview.The committee determines the total target compensation level for the CEO, as well as the appropriate mix of the compensation elements, based on prevailing practices in the comparator group. The CEO relies on comparator group standards to recommend, for the committee’s review and approval, the levels and mix of elements for allthe balance of our executive officers. Although the committee is not bound to mirror the comparator group standards when it makes decisions on compensation levels and the mix of elements, the committee generally relies heavily on the identified competitive norms to ensure that we can compete for executive talent. The committee also reviewed the relationship between the CEO’s compensation and the compensation for the other NEOs. TheIn 2011, the committee determined that theinternal pay relationships are appropriate in light of the committee’s understanding of the typical pay relationships at other companies.

We list the primary elements of our executive compensation below, together with relevant information about each element:

24

26

25

The percentage of total compensation allocated to each element varies by individual. The committee determines the appropriate mix of these elements after considering prevailing practices in the comparator group. Our executives also participate in certain other benefits, such as general health, life and disability insurance plans, most of which are available to all salaried employees.

As a guideline, the committee intends that expenditures with respect tothe base salaries, total cash compensation (salary and annual cash incentive), and total compensation opportunities (total cash compensation plus the grant date value of long-term incentive awards) extended to our NEOs approximate the median of the comparator group. The committee believes that managing overalltotal target pay to the market median allows us to attract, motivate, and retain the quality executive talent Olin needs. Actual pay levels for any individual NEO, however, may be below or above the median.market median for that executive’s particular role. The following tablegraph illustrates our pay objectives and our2011 target compensation positioning for the NEOs as a group, relative to our NEOs in 2010:pay:

27

Our general practice for an executive who is new in his/her position is to establish compensation opportunities below the market, and to increase itthem to market level over several years, assuming that performance warrants such increases. Other material increases in compensation generally relate to promotions or added responsibilities. For example, when Mr. Rupp became CEO in 2002, his base salary was well below the median of the comparator group, reflecting his new appointment to the CEO position. In the following years, Mr. Rupp’s salary moved closer to the market norm, and since 2008 his base pay has closely approximated the comparator group median.

Salary.    The committee generally adjusts NEO salaries on an annual basis, but when warranted by cash flow or other considerations, this period has been extended to 18 months or more, and we have frozen executive base salaries for periods of time. For example, in 2010 no salary increases were granted to any NEO, other than promotional raises effective on October 1, 2010 for Messrs. Fischer, Pain and McIntosh. The next raises for those individuals took effect January 1, 2012, fifteen months later. Mr. Rupp received an increase in his salary in April of 2011 (two years after his last salary increase in April of 2009), and the committee did not increase his salary for 2012. In the past 10 years, we have not decreased base salary for any NEO.

Annual Cash Incentive (Non-equity Incentive Plan Compensation).    NEOs participate in the Senior Management Incentive Compensation Plan, or SMICP, an incentive plan approved by our shareholders. The SMICP provides NEOs with annual cash incentive opportunities comparable to the terms and conditions for awards of cash bonuses to our other executives (who participate in our Management Incentive Compensation Plan, or MICP). Using the SMICP for our NEOs allowsis intended to allow us to deduct payments to those individuals subject to the deduction limits of Section 162(m) of the Internal Revenue Code of 1986, as amended (the Code).

The mechanics of the SMICP operation in 20102011 were as follows:

26

Although the committee exercises discretion to reduce annual incentives under the SMICP, it may not increase the payments above the maximum awards established as described above, and the payout under the SMICP may not exceed 200% of the executive’s base salary. When using its discretion to appropriately size annual incentives for 2010,2011, the committee examined achievement with respect to financial goals and non-financial strategic accomplishments. In determining SMICP payments for NEOs with company-wide responsibility (Messrs. Rupp, Fischer, McIntosh and Pain), the committee considered Olin’s financial performance, especially the generation of $64.8$128.5 million of net income and earnings per share performance, (which included the full impact of a restructuring charge), as well as other accomplishments relating to the satisfactionachievement of strategic sales goals, substantial operational improvements and restructuring initiatives, which will have longer term impact.

28

For Messrs. McIntosh and Hammett,Mr. Chirumbole, who each had divisional responsibility in 2010,for 2011, the committee adopted a blended consideration of Olin and divisional accomplishments and applied a more formulaic approach to SMICP award determination. The committee decided that 25% of each officer’shis overall award should be a function of company-wide financial and non-financial accomplishments and 75% of his overall incentive award should reflect divisional performance (where division financial objectives were assigned a 75% weight and division non-financial strategic objectives were assigned a 25% weight for the applicable division)weight). The committee’s discretionary decisions with respect to Mr. Chirumbole’s 2011 SMICP awards for 2010 for Mr. McIntoshaward reflected the Chlor Alkali division’s pre-tax income, operating cash flow and return on capital, each of which exceeded expectations, as well as significant productivity improvements, bleach strategy implementation and long-term strategic plans. For Mr. Hammett, the committee’s decision reflected the Winchester division’s pre-tax income, operating cash flow and return on capital, each of which exceeded planned performance, coupled with operational improvements, favorable pricingimprovements’ and execution of a strategystrategic initiatives to impact the longer term cost structure of the business.

After reviewing these results, the committee used its discretion to approve for Mr. Chirumbole the SMICP paymentspayment identified in the Summary Compensation Table. EachAll of thesethe approved awards representsrepresent a reduction in award level from the recipient’s maximum permissible portion of the SMICP pool.

Long Term Incentive Compensation.    In 2010,2011, we allocated the value of long-term incentive compensation awards equally between performance shares and stock options. This combination of awards was deemed by the committee to optimize our emphasis on achieving specified performance goals that drive investor value and generating long-term appreciation in Olin’s stock price. The committee makes all equity awards to executive officers (both performance shares and stock options). The committee believes that its determination of stock option and performance share awards is highly representative of external market practices, based on information pertaining to compensation standards across the comparator group.

All long-term incentive compensation plan participants are assigned target award levels at dollar values deemed by the committee to be competitive with external market practices, based on information on the comparator group. The sum of all individual target awards represents our overall long-term incentive award value. When determining actual stock option grant sizes and performance share award levels, the committee compares our return on capital and total shareholder return to that of the Performance Share Comparison Group. Our relative performance against this group influences the pool of shares the committee makes available for grants to long-term incentive program participants.

The process the committee follows to determine stock option and performance share awards is described below.

2729

Performance Shares.Shares.    Half the value of each participant’s 20102011 long-term incentive target award value was delivered in performance shares. The number of performance shares awarded to each participant was formulated by dividing half the participant’s target award value by the economic value of a performance share. Early in 2010,2011, each executive receivedwas extended the opportunity to earn a target number of performance shares that were contingent on performance through the end of 2012.2013. The total number of performance shares that vest and will be paid to each executive may vary between 25% and 150% of his or her target number, depending on our average annual return on capital for the three years ending December 31, 2012,2013, in relation to the average annual return on capital generated by the Performance Share Comparison Group for that period, as set forth in more detail inperiod. The following chart identifies the chart below:percentage of target shares that vest with our performance:

Olin’s return on capitalThe table below identifies our performance againstand the Performance Share Comparison Group forpercentage of the relevant three-year period is determined after the data pertaining to the Performance Share Comparison Group become available (typically the summer after the three-year period ends). At that time, thetarget number of performance shares earned is calculated and paid.

The committee believes this performance share program provides a challenging level against which our performance is measured, as evidenced by the following table, which illustrates actual results of the return on capital matrixplan participants for each of the last fiveeight three-year periods:

Stock Options.    The remaining half of each participant’s long-term incentive target award value is delivered in stock options. Stock options are granted annually from a committee-approved pool of option shares. The pool of stock options available for issuance each year equals half the value of the

30

overall long-term incentive award value, divided by the Black-Scholes value of options for our common stock (not to be lower than 20% of the then-current market price of our common stock). This formulated pool of shares increases or decreases based on our trailing three-year total shareholder return (TSR) compared to the TSRs generated by the Performance Share Comparison Group, as follows:

28

We believe the Performance Share Comparison Group represents our primary competition for investment capital, and therefore comprises an appropriate comparison group for performance purposes. We use TSR, which represents the increase in the fair market value of our common stock over the three-year period, including reinvestment of dividends, to tie executive rewards to our shareholders’ interests. The calculation of TSR includes all dividends paid by the companies, consistent with the calculations for our Performance Graph included in our Form 10-K. As with our performance share program described above, the committee believes that formulating the stock option pool this way heightens the challenging character of thefurther ties executive compensation opportunities available to our executives. As theshareholder value. The table below demonstrates,shows our TSR and effect on the size of our stock option pool increased in size only twice infor the past fiveeight years:

31

The number of stock options granted to individual long-term incentive plan participants reflects the portion of the available pool represented by the individual’s target award. The committee (or the CEO, in the case of non-officers) may increase or decrease the option grant for an individual by up to 25% from the target level, although that discretion has not been exercised.

We approve option awards at the first committee meeting each year. In 2010,2011, the first committee meeting was January 22, 2010.31, 2011. At that meeting, the committee approved the granting of options effective on February 5, 2010,11, 2011, with an exercise price of $15.68$18.78 per share, the average of the high and low per share sales price of our common stock on the New York Stock Exchange on February 5, 2010.11, 2011. When the first scheduled meeting occurs before or near the time we release our year end earnings report, the committee has granted stock options:

The practice ensures that the exercise price for stock options reflects all current information. Although we have no formal policy on granting options at a time when inside information may exist, the committee follows the procedure we describe above when necessary to ensure that option exercise prices reflect full disclosure of earnings information. We have not engaged in “back dating” of options, as our policies do not allow back dating. In addition, our equity plans do not permit option grants with an exercise price below the fair market value of our stock on the effective date of the option grant.

Our CEO also has authority to grant a very limited number of options at other times during the year (no more than 50,000 total shares or 5,000 shares per employee), but may not grant options to anyone who is an officer within the definition of the rules under Section 16 of the Exchange Act, or “back date” any options. Consistent with the terms of our equity plans, options granted by our CEO may not have an exercise price below the fair market value of our stock on the effective date of the option grant.

Other Compensation.    The committee occasionally approves payments to an individual or group of employees to reflect special circumstances. Effective February 5, 2010, the committee granted special restricted stock units totaling 89,998, to four of the NEOs (reflected in the Summary Compensation Table and the Grants of Plan-Based Awards Table) and to 14 other employees. These

29

awards serve as a retention incentive for a key group of officers and employees and also reward their extraordinary efforts and contributions to our restructuring activities over the past few years.

We also offer a small number of other personal benefits to groups of employees. We provide some benefits, such as a portion of health insurance premiums and certain retirement benefits, to all salaried employees. We tie these benefits to competitive practices in the market, a practice the committee believes enables us to attract and retain executives with the talents and skill sets we require. Other items, such as certain life insurance benefits and the retirement and change in control benefits described below, are provided only to our NEOs and other senior managers. Historically,In the past, we also provided automobile expenses and financial counseling services to some of our NEOs, but terminated those perquisites at the end of 2010. The committee occasionally approves special restricted stock awards to an individual or group of employees to reflect special circumstances, although no such awards were made to NEOs in 2011.

Retirement Benefits.    We offer retirement benefits as part of the package to recruit and retain employees, as well as to contribute to their financial security in post-employment years. Our retirement benefits also reflect an individual’s contributions over his or her career with the company, as those benefits are based in part on the employee’s service. In general, we establish retirement benefits based on comparable programs offered by competitors. The committee believes nonqualified supplementalthat retirement plans like ours are commonly provided to executives at other companies, and offering these benefits helps us remain competitive for qualified senior-level executive talent. We periodically re-evaluate and update those plans to respond to changes in the market.

32

The following chart summarizes the benefits under our active retirement plans for salaried employees:

30

As part of our ongoing evaluation of benefit plans, in 2005, we amended the Olin Corporation Employees Pension Plan (Qualified Plan) to eliminate participation for salaried employees hired on or after January 1, 2005. As of December 31, 2007, we froze defined benefit pension accruals for salaried participants under that Plan, as well as the Olin Supplementary and Deferral Benefit Pension Plan (Supplemental Plan) and the Olin Senior Executive Pension Plan (Senior Plan). Although benefit accruals were frozen at the end of 2007, employment after that time counts toward years of service for vesting and early retirement eligibility.

The Supplemental CEOP, the Supplemental Plan and the Senior Plan are unfunded, nonqualified deferred compensation plans for the NEOs and a select group of other senior management employees. Because these three plans are unfunded, participants receive benefits only if we have the financial

33

resources to make the payments when due. The committee believes that historically it was common for companies to offer these kinds of nonqualified retirement supplements are commonly extended to executives at other companies, and by offering these benefits wehas allowed us to remain competitive in the market for qualified senior-level executive talent. We describe the terms of our retirement plans in more detail in the narrative discussion following the table entitled “Pension Benefits” below.

Risk Assessment.    Management and the committee regularly evaluate the risks involved with our compensation programs. In 2012, we conducted a comprehensive risk assessment. The risk assessment included compiling an inventory of incentive plans and programs, and conducting an analysis of the risk involved with each. The assessment considered factors such as the plan metrics, number of participants, maximum payments, and risk mitigation factors. The committee reviewed the risk assessment and concluded it did not believe any of our compensation programs or policies create risks that are reasonably likely to have a material adverse impact on Olin. Based on this conclusion, we implemented no material changes to our compensation policies or practices after our risk assessment.

Change in Control Agreements.    We provide change in control agreements to our senior management to ensure that our executives work to secure the best outcome for shareholders in the event of a possible change in control, even if it means that they lose their jobs as a result. As a retention incentive, each of our senior executives also has an agreement that provides certain benefits if the executive’s employment is terminated without cause. These agreements are described in detail under the discussion following the “Summary Compensation Table” and under the caption “Potential Payments Upon Termination or Change in Control.” As noted above, in 2011, we provided notice of termination of existing change in control agreements when they expire in 2014, and indicated the committee’s intention to replace those agreements with arrangements consistent with then-current market practices.

The committee gives careful attention to all aspects of executive compensation and for the reasons discussed above remains confident that our executive compensation program satisfies our objectives.

Tax and Accounting Considerations

All elements of compensation, including salaries, generate charges to earnings under generally accepted accounting principles (GAAP). We generally do not adjust compensation based on accounting factors, but we consider the tax effect of various types of compensation. The committee considers the Code Section 162(m) limit on deductions for compensation over $1 million, and designs our stock options, the largest portion of our performance shares and our annual cash incentive to meet the exemption for “performance-based” compensation from this deductibility limit. It is possible, however, that portions of these awards will not qualify as “performance-based compensation,” and, when combined with salary and other compensation to an NEO, may exceed this limitation in any particular year.

Code Section 409A implemented tax rules applicable to nonqualified deferred compensation arrangements, and Olin has taken steps to comply with such rules to the extent applicable.

31

In early 2009, our board, at the recommendation of the committee, adopted a “clawback” policy that allows Olin to recover all or a portion of payments under the SMICP or the MICP and performance share awards from certain executives. To recover compensation, our board or the committee must determine that the executive was grossly negligent or engaged in intentional misconduct that was a “significant contributing factor” to:

34

Each executive who participates in the SMICP or the MICP is subject to the clawback policy. Amounts that we recover are not included in calculating that executive’s benefits under our Supplemental CEOP, and our recovery of amounts under the policy does not constitute an event that triggers benefits under our severance agreements.

In addition to the clawback policy, our equity plans provide that if a participant in that plan renders service to one of our competitors, or discloses confidential information without our consent, or violates other terms of the plan, the committee may terminate any unvested, unpaid or deferred awards held by the participant, or may require the participant to forfeit benefits received under the plan within the six months before the participant’s action.

Our severance arrangements described below under “Potential Payments Upon Termination or Change in Control” provide that we will “gross up” the amount of excise tax, if any, due on “excess golden parachute payments” provisions under Code Section 280G. The committee considered this benefitAs noted above, we provided notice of termination of these change in approving the terms of those agreements.control agreements upon expiration in 2014, to be replaced with arrangements consistent with then-current market practices.

Stock Ownership Guidelines

We describe our stock ownership guidelines for directors under the heading “Director Compensation” below. Our stock ownership guidelines for employees require executive officers and certain other senior managers to maintain specified ownership levels of our stock within 5 years after the guideline applies. Our committee monitors compliance with the stock ownership guidelines annually. To determine “stock ownership” under the guidelines, we include, in addition to shares the individual owns outright, restricted stock and restricted stock units, shares held in the executive’s CEOP account,and Supplemental CEOP accounts, shares subject to vested stock options with an exercise price below the current market price and one-half of the total target performance share awards payable in stock.

Effective December 2010, we revised our stock ownership guidelines from a required number of shares to an approach based on a multiple of year end base salary. The new guidelines applicable to our NEOs are set forth below:

Our CEO and twothe other NEOs met these new guidelines at year end. Our other two NEOs were promoted to the senior vice president level in October 2010, and have five years to attain the higher ownership guidelines.

3235

SUMMARY COMPENSATION TABLE

The table below summarizes the total compensation paid to or earned by each of the NEOs for the fiscal years ended December 31, 2011, 2010 2009 and 2008.2009:

3336