NEW YORK (Reuters) - Activist investor Mantle Ridge has secured enough support from Air Products and Chemicals ( APD ) investors to win several seats on the industrial gases company's board of directors, two people familiar with the matter said on Wednesday.

Investor votes are still being counted before Air Products' annual meeting on Thursday and the final number of board seats that Mantle Ridge will get has not been determined. But the sources told Reuters Mantle Ridge is currently on track to secure three seats.

Representatives for Mantle Ridge and Air Products were not immediately available for comment.

The vote will end one of the most fiercely contested board battles in recent memory, with an octogenarian chief executive facing off against a hedge fund manager who helped put him onto the company's board a decade ago.

Mantle Ridge, run by Paul Hilal, argued that Air Products needs to lay out a succession plan for CEO Seifi Ghasemi, allocate its capital differently and scale back on risky projects. The investment firm urged investors to elect its four candidates to the nine-member board.

The company countered that it was well on its way to lay out a succession plan for Ghasemi and that the election of any Mantle Ridge nominee could create confusion for the company's leadership and direction.

But three proxy advisory firms, whose recommendations often influence how investors cast their votes, sided with Mantle Ridge, arguing that change is needed at Air Products and that investors should elect at least three of the activist investors' candidates.

A number of large investors including Norwegian sovereign wealth fund Norges Bank Investment Management said they would be voting for all four of Mantle Ridge's nominees.

For Hilal, this marks the second battle at Air Products after he was instrumental in finding new directors, including Ghasemi, when hedge fund Pershing Square Capital Management battled with the company more than a decade ago.

Hilal founded his own firm in 2016 and has since run campaigns at railroad CSX, food services and facilities services provider Aramark and retailer Dollar Tree. At all companies, he quickly helped install a new CEO.

For the fight at Air Products, he lined up industrial gases executive Eduardo Menezes a former executive vice president for Europe, Middle East and Africa at Linde who also previously worked at Praxair in senior roles.