Forest Harvest Opportunity Act

Forest Harvest Opportunity Act - Directs the Secretary of the Interior, within 30 days of a timber purchaser requesting an economy-related contract extension of a qualifying contract for the sale of timber from land administered by the Bureau of Land Management (BLM) between the Secretary and the purchaser, to modify the contract to add three years to such contract's expiration date.

Defines qualifying contract as a contract, executed on or before December 31, 2008, for the sale of timber from BLM lands: (1) for which there is unharvested volume remaining; (2) for which, within 90 days of enactment of this Act, a timber purchaser makes a written request to the Secretary for an economic related contract extension; and (3) that has not been terminated prior to the request for an extension.

Requires the timber purchaser to waive any and all claims its has against the United States involving the qualifying contract that exist on the date such contract is modified.

Prohibits anything in this Act from affecting any claim by the United States against any timber purchaser, including those claims that arose under a qualifying contract before the date on which its expiration date was extended.