Songbird Estates plc is engaged in the management of its investment in its subsidiary, Canary Wharf Group plc, which is the holding company for Canary Wharf Group, which specializes in integrated property development, investment and management focusing primarily on the Estate and Central London. Canary Wharf Group is also involved, through joint ventures, in the redevelopment of 20 Fenchurch Street. At December 31, 2011, Canary Wharf Group�s investment property portfolio comprised 16 completed properties (out of the 35 constructed on the Estate) totaling approximately seven square meter feet NIA. At December 31, 2011, the investment property portfolio was 96.5% let. During the year ended December 31, 2011, over 57,000 square feet of leases were completed in One Canada Square. In January 18, 2012, Canary Wharf Group completed its acquisition of WWLP and associated companies and was granted a new overriding 250 year lease of Wood Wharf. On July 2011, it acquired Shell Centre.