OLIN Corp — Director's Dealing 2011

May 5, 2011

SEC Form 4 — Statement of Changes in Beneficial Ownership

Issuer: OLIN CORP (OLN)
CIK: 0000074303
Period of Report: 2011-05-03

Reporting Person: Chirumbole Frank W (President, Chlor Alkali Prod.)

Non-Derivative Transactions

Date	Security	Code	Shares	Price	A/D	Holdings After	Ownership
2011-05-03	Common Stock $1 par value	M	12000	$16.10	Acquired	25548	Direct
2011-05-03	Common Stock $1 par value	S	12000	$25.05	Disposed	13548	Direct

Derivative Transactions

Date	Security	Exercise Price	Code	Shares	A/D	Expiration	Underlying	Ownership
2011-05-03	Employee Stock Option Right to Buy	$16.10	M	12000	Disposed	2012-02-13	Common Stock (12000)	Direct

Holdings (Non-Derivative)

Security	Shares	Ownership
Common Stock $1 par value	712.0563	Indirect

Footnotes

F1: This transaction was executed in multiple trades at prices ranging from $25.01 to $25.13. The price reported above reflects the weighted average sale price. The reporting person hereby undertakes to provide upon request to the SEC staff, the issuer or a security holder of the issuer full information regarding the number of shares and prices at which the transaction was effected.

F2: The figure represents shares of Olin Common Stock held under the Olin Common Stock Fund of the Olin Corporation Contributing Employee Ownership Plan (CEOP), a tax-conditioned plan reflecting transactions exempt under Rule 16b-3, as reported by the CEOP Plan Administrator as of April 28, 2011.