UPDATE 1-Icahn offers to buy Oshkosh Corp for $32.50 a share

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Oct 11 (Reuters) - Activist investor Carl Icahn on Thursday offered to buy all outstanding shares of U.S. truckmaker Oshkosh Corp for $32.50, a 21 percent premium to their Wednesday closing price.

Icahn, who is already Oshkosh's largest shareholder with a 9.45 percent stake, said that he plans to nominate a slate of directors for election at the company's next annual meeting and that his offer would be subject to the election of those directors.

Oshkosh did not immediately respond to a call seeking comment. Shares of the company surged 14 percent to $30.57 on the news.

Icahn said in a statement that a tender offer would expire in 45 days, but that if at least 25 percent of the company's outstanding shares were sold to him he would extend it.

Should he be able to boost his stake to 50.1 percent, he added, "we will demand that the current board, in accordance with its fiduciary duty to stockholders, accelerate the upcoming annual meeting to allow the prompt election of our slate of directors so that the tender offer can close quickly."

(Reporting By Scott Malone; Editing by Gerald E. McCormick)

((scott.malone@thomsonreuters.com)(+1 617 856 4342)(Reuters Messaging: scott.malone.thomsonreuters.com@reuters.net))