Deals & DealmakersFive firms take 23,645 s/f at WKO’s 437 Madison Ave.Christian Brazil BautistaOctober 12, 2017October 12, 2017 by Christian Brazil BautistaOctober 12, 2017October 12, 20170922 Five companies have signed lease deals totaling 23,645 s/f at the William Kaufman Organization’s 437 Madison Avenue. Financial services firm Mercantil Bank (6,007 s/f), software company Fidessa