One of New York City's largest landlords, Thor Equities, has offered more than $2.1 billion in cash to buy the Empire State Building, the real estate firm's broker said on Thursday.
It was the third unsolicited offer for the landmark skyscraper, which is set to become the centerpiece of a publicly traded real estate investment trust.
Thor Equities confirmed the offer but not the price. A representative from Malkin Holdings, which oversees the Empire State Building's investors and operations, could not immediately confirm that it has received the offer and declined further comment.
Broker Jason Meister of Avison Young, which is representing Thor Equities, said the offer was all cash.
(Read More: NY Judge May OK Empire State Building REIT Plan)
Earlier this week, Malkin Holdings said in a letter to investors that it was reviewing two unsolicited bids—one for $2.1 billion and the other for $2 billion—to buy the 102-story building. The letter was included in a filing with the U.S. Securities and Exchange Commission.
Malkin Holdings had said it would consider the two previously unsolicited offers, consistent with its fiduciary duties.
In addition to its presence in New York, Thor Equities owns and develops urban real estate throughout the United States, Latin America and Europe.
Meister Seelig & Fein, the law firm representing investors who oppose the REIT plan, disclosed a letter last week from privately held Cammeby's International Group offering to buy the building for $2 billion.
The second bidder's identity was not disclosed in the most recent SEC filing.
Malkin Holdings led the plan to put the Empire State Building and more than 17 other properties into a real estate investment trust called Empire State Realty Trust Inc, which would be publicly traded under the proposed symbol "ESB" on the New York Stock Exchange. Investors recently approved the REIT plan.
Malkin Holdings, the Helmsley Trust and investors would have to approve a sale. The Helmsley Trust is the majority owner of the company that owns the building's sublease, which expires in 2076.
An appraisal conducted last summer valued the Empire State Building at about $2.33 billion, after debt, according to the SEC filing. Including the mortgage, the historic skyscraper is valued at about $2.53 billion, that appraisal showed.