(Bloomberg) -- Activist investor Jonathan Litt may put forth a slate of directors for Mack-Cali Realty Corp.’s board because he continues to believe the company is refusing to engage with a potential buyer, according to people familiar with the matter.

Litt’s Land & Buildings Investment Management, which holds more than 2 percent of Mack-Cali’s stock, sent a letter last month to the company’s board saying it was aware of an unidentified buyer interested in acquiring the $1.8 billion real estate investment trust, according to a copy of the letter obtained by Bloomberg.

Land & Buildings continues to believe there have been expressions of interest in the company since then and plans to nominate a slate of directors if Mack-Cali doesn’t entertain those offers, said the people, who asked not to be identified because the matter is private.

A representative for Land & Buildings declined to comment. A representative for Mack-Cali, based in Jersey City, New Jersey, also declined to comment.

Litt sat on Mack-Cali’s board for more than two years. In November 2014, eight months after Litt joined the board, the company said then Chief Executive Officer Mitchell Hersh was stepping down and wouldn’t seek re-election as a director.

Litt resigned from the board in August 2016 after Mack-Cali’s shares had risen more than 32 percent. The company said at the time that his resignation wasn’t the result of any disagreement with it or its strategy.

To contact the reporters on this story: Scott Deveau in New York at sdeveau2@bloomberg.net;Gillian Tan in New York at gtan129@bloomberg.net

To contact the editors responsible for this story: Elizabeth Fournier at efournier5@bloomberg.net, ;Alan Goldstein at agoldstein5@bloomberg.net, Michael Hytha

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