Mr. Penson is among higher-profile investors in a dispute between Malkin Holdings and a number of the unitholders in Empire State Building Associates LLC, which owns the building. The dissidents say disadvantages to a REIT include the potential loss of a reliable income stream that should rise as renovations are finished, while the Malkins have said their proposal would give investors liquidity and greater growth opportunities. "You've got an awful lot of litigative real estate owners in New York," Lawrence Longua, an associate professor at New York University's Schack Institute of Real Estate, said in a phone interview. "But they're usually litigative with respect to their tenants and brokers. To see this happening at this level, if you will, I would use the word extraordinary," he said of Penson and Malkin.