Equity Office Properties ( EOP) met with representatives from a Vornado Realty ( VNO)-led group that has recently launched a bid to trump the company's current buyout agreement with Blackstone Group.

Equity Office said Monday that its board has met to consider the Vornado buyout offer. The company also has provided due diligence information to the group, which also includes real estate investment firms Starwood Capital and Walton Street Capital.

The group last week disclosed a $52-a-share offer for Equity Office, consisting of 60% cash and 40% Vornado stock. The Blackstone agreement would pay investors $48.50 a share.

Equity Office said it expects the Vornado group will be in a position to submit a definitive proposal by Jan. 31. The company, though, said it hasn't changed its recommendation regarding the Blackstone agreement. The office owner's shareholders are scheduled to vote on that deal Feb. 5.

The Blackstone deal is valued at $36 billion, including debt. The transaction would rank as the most expensive real estate deal ever, as well as one of the biggest leveraged buyouts in any industry.

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