Billionaire Carl Icahn's investment firm, Icahn Enterprises LP, sweetened its offer for a third time to buy shares of Federal-Mogul Holdings Corp. it does not already own.

The latest offer of $10 per share represents a discount of 3 percent to Federal-Mogul's Friday close but is double the closing price on Feb. 26, the day before Icahn made his first offer of $7 a share.

Federal-Mogul's shares were down 2.7 percent at $10.03 on Tuesday.

Icahn Enterprises raised the offer for the first time to $8 per share in June and to $9.25 per share in September.

The latest offer comes after Icahn failed to get enough Federal-Mogul stock owners to tender their shares in favor of the deal.

Icahn Enterprises, which owns about 82 percent of the auto parts maker, said the $10 per share offer was its "best and final" price.

The investment firm will pay about $304.3 million for the 18 percent stake under the latest offer, according to Reuters calculations.

Icahn Enterprises, which bought auto parts retailer Pep Boys-Manny Moe & Jack for $1 billion in February, is bidding for the remaining stake in Federal-Mogul as it builds on its holdings within the auto parts supply chain.