Icahn, who has nominated four candidates to the company's board, said in an open letter to shareholders that he had asked a Delaware court to allow him to release non-public information to shareholders that would shed light on the matter.

He wants the information to be released before the company's annual meeting on August 15.

Icahn said Forest publicly filed a major licensing agreement it reached with Cypress Bioscience in 2004, and said the agreement contained a change-of-control provision that was an attempt to "surreptitiously implement an anti-takeover measure." And he suggests other licensing agreements might contain similar measures.

Forest scoffs at Icahn's theory, saying change-of-control agreements are standard in the industry, and are typically required by joint venture partners to ensure that their products are developed and commercialized by the company with whom they signed the agreement.

"These provisions address circumstances under which someone trying to acquire Forest might have a directly competing product or product in development and a possibility of disfavoring the joint venture partner's licensed product," Forest said. "Our joint venture partner might not be confident that this new party would devote the appropriate resources and support to its product."

Forest said Icahn and Eric Ende, a former Merrill Lynch analyst who is leading the proxy fight on behalf of Icahn, should know this "given their purported pharma experience."

Icahn has attacked Forest, which makes the antidepressant Lexapro and Alzheimer's drug Namenda, on multiple levels. He believes it is trying to sell products in too many therapeutic areas and that its sales force is therefore inefficient. He recommends some products be divested.

He also claims that the company has promoted the son of 84-year-old Chief Executive Howard Solomon beyond his abilities with the aim of installing him in the top job.

Forest contends it has taken multiple measures to improve its corporate governance and that its strategy is the right one to promote growth.

A regulatory filing by Forest on Thursday noted that the company had agreed to make changes to its corporate governance as part of a proposed settlement with shareholders who sued Forest for breach of fiduciary duties, including making false and misleading statements about its executive compensation program.

In its statement on Friday the company cited Dean Robert Clark of Harvard Law School, an expert who was asked to consult on the company's corporate governance practices, who, Forest quoted him as saying, is "very pleased with the Forest Board's constructive attitude, active participation and responsiveness to the governance topics that we discussed."

Icahn said he had also asked the court to rule that he be allowed to disclose another issue related to the licensing agreements that he thinks is a "smoking gun."

The company's shares closed up 0.9 percent at $33.76 on the New York Stock Exchange.

(Reporting by Toni Clarke; editing by John Wallace, Jeffrey Benkoe and Bernard Orr)

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