JetBlue stock is taking off after Carl Icahn revealed his stake in the company

Beleaguered airline JetBlue has a lot to thank Carl Icahn for this week. The airline’s stock rose more than 15% during morning trading on Tuesday (Feb. 13) after the activist investor revealed he holds a 9.91% stake and may be seeking a seat on itsboard.

Icahn revealed his stake in the airline in a USSecurities and Exchange Commission (SEC)filling on Monday. In the filing he described JetBlue stock as undervalued, making it “an attractive investment opportunity.”

The filing addedthat Icahn continues discussions with JetBlue “regarding the possibility of board representation.” The news comes as the company is going through a transfer of leadership. Monday marked former president and chief operating officer Joanna Geraghty’s first day as the airline’s new CEO.

“We are always open to constructive dialogue with our investors as we continue to execute our plan to enhance value for all of our shareholders and stakeholders,” JetBlue told Quartz in a statement.

JetBlue’s recent struggles

Icahn’s investment in the airline aligns coincides the company’s efforts to navigatesome turbulence. JetBlue reported a 4.5% drop in revenue in the three months ending Dec. 31, according to its most recent quarterly earnings report, along with a loss of $104 million.

The company has alsosuffered recent legal blows. In January, a judge blocked JetBlue’s planned $3.8 billion acquisition of Spirit Airlines. The US Department of Justice hadfiled a lawsuit to stop the merger, claiming it would raise prices for consumers. Last year, another judge ruled that the company must end its regional partnership with American Airlines, with the Justice Department again arguing the alliance would hurt consumer purchasers.

Icahn’s recent moves

Icahn is recovering from a tough year, too. Last spring, Hindenburg Research published report calling Ichan Enterprises, the billionaire’s investment firm, overvalued. Shares of the company dropped in half. 

On the upside,Icahn also successfully led a campaign against Illumina’s acquisition of cancer test maker Grail, which he claimed was mismanaged for shareholders. More recently, Ohio-based American Electric Power announced Monday that it reached a deal with Icahn Capital, giving Icahn control of two board seats.