Billionaire investor Carl Icahn accused Forest Laboratories of using a licensing agreement to block takeovers and renewed his lobbying for other shareholders to vote for his board candidates at the company's annual meeting next week.

Icahn is the second-largest Forest Laboratories Inc. shareholder, and for the second consecutive year, he has nominated four alternative candidates to the drugmaker's board. None of his nominees were elected last year.

The activist investor said Friday that he believes Forest added a provision to a licensing agreement with Cypress Bioscience to prevent takeovers. The provision allows the license to be voided by Cypress if there is a change of control at Forest that was not approved by the Forest board.

"It seems to us that the only purpose for a provision like this is entrenchment at Forest," Icahn said.

Forest Laboratories said Icahn has twisted the facts in an attempt to manipulate the results of the election.

The company said in a letter to shareholders that the agreements are not structured to deter a potential acquisition but follow the standard in the pharmaceutical industry. In addition, it said such agreements were required by its joint venture partners to protect their proprietary creations.

Icahn said he went to court to get the company to turn over documents that would show whether a similar provision exists in other agreements. He said he's also asking the court to allow him to share information about those provisions with shareholders because Forest has refused to permit it.

"In addition, Forest is insisting that we may not tell you about another issue related to these license agreements," Icahn wrote. "We think this issue is a smoking gun, and have also asked the court to rule that we should be allowed to disclose this information to stockholders before the annual meeting."

The company says the court set the timing of the disclosures in a schedule that Icahn approved. Forest said the company is complying with its terms.

Icahn also has criticized the company for, among other things, failing to prepare for the loss of patent exclusivity on its antidepressant Lexapro. Generic versions of Lexapro went on sale in early 2012 and Forest cut its income and revenue forecasts in June, saying competition was stiffer than it had expected.

Icahn has said Forest's directors lack independence because they are former executives or have other longstanding ties to the company. Forest Laboratories has said eight of its directors are independent and five of them have joined the company in the last six years. It also has said its own nominees have the right mix of experience and leadership.

The company also noted in a letter to shareholders that it consulted with a corporate governance expert and enhanced its framework after that. The company plans to continue to meet with the expert annually to ensure it is following the best practices for its board.

Forest shareholders will elect the company's board at a meeting on Aug. 15.

Shares of Forest Laboratories rose 24 cents to $33.71 in afternoon trading, while shares of Icahn Enterprises LP fell 29 cents to $40.20.