(Reuters) – Hedge fund managers Carl Icahn and Darwin Deason demanded on Monday that Xerox Corp (XRX.N) explore strategic alternatives and said they would join forces to elect four new members to the board, prodding the company’s shares higher.

Icahn and Deason, who together own over 15 percent of Xerox, last week separately called on Xerox to break off or renegotiate its joint venture with Fujifilm Holdings Corp (4901.T), saying it was unfavorable to the U.S. company.

In Monday’s letter, Icahn reiterated his demands for a renegotiation or termination of the JV and the replacement of Xerox’s Chief Executive Jeff Jacobson. (bit.ly/2G6b4WO)

FILE PHOTO: The logo of Xerox company is seen on a building in Minsk, Belarus, March 21, 2016. REUTERS/Vasily Fedosenko/File Photo

The Wall Street Journal reported on Sunday the two investors – respectively the biggest- and the third-biggest shareholders in Xerox – were pushing for it to consider options, including a sale of the firm.

Xerox was not immediately available for a comment on Icahn and Deason’s demands.

Icahn’s stake in Xerox dates back to 2015, when he called the shares “undervalued”.

Shares of Norwalk, Connecticut-based Xerox rose as much as 4 percent to $33.03 on NYSE within the first 30 minutes of market open. The shares later on pared gains and were trading at $32.21, up 1.4 percent.

Reporting by Muvija M in Bengaluru; Editing by Arun Koyyur