 The preservation of the staircase became a matter of dispute since May 11, 2006, when it was listed as one of America's Most Endangered Places by the National Trust for Historic Preservation.The stairs occupied part of the site of a new office building which the Port Authority of New York and New Jersey was contractually obliged to clear before the site was turned over to developer Larry Silverstein of Silverstein Properties, who in turn has a contractual obligation to develop the site as the 200 Greenwich Street office building, which is also referenced as "Tower 2" in the master plan.The World Trade Center Survivors' Network urged the Port Authority and Silverstein to make a commitment to preserve the stairs, but neither made a public decision on the issue.