A real estate fund run by the Goldman Sachs Group, had walked away from a $1.3 billion deal with a unit of Lehman Brothers Holdings.  The deal was to buy a portfolio of 10 office buildings in a suburb of Washington. Now, Lehman Brothers is suing that Goldman affiliate, seeking $100mn in damages, alleging the fund's "unjustified" termination of the deal just 2 days before the sale was to close.  The suit seeks to force Goldman's fund to close on the deal;  Lehman also is seeking to keep Goldman's $100 million deposit.  Lehman's proceeds from the deal would amount to "not less than $385 million." According to the lawsuit... Goldman backed out of the deal on Tuesday because, as Goldman said, Lehman had failed to disclose certain leasing agreements, and that some tenant documents were inconsistent with terms of the deal, according to the complaint.  Lehman rejected those grounds as "pretextual," saying Goldman was looking for an excuse to "avoid its contractual obligations." The purchase agreement gave Lehman 15 days to correct any shortcomings in disclosures, and Goldman breached the deal by failing to provide that window, Lehman alleged. The case: Rosslyn LB Syndication Partner LLC v. Usreo/Rosslyn Investors LLC, U.S. Bankruptcy Court, Southern District of New York, No. 11-2764. [Reuters, 10/6/11] and [WSJ, 10/7/11].