 In 2010, after a 10 year campaign by proposer, Peter Davies, English Heritage agreed to commemorate John Lennon's London address, and Yoko Ono unveiled a blue marker plaque at the site, making it an English Heritage "building of historical interest".34 and the adjoining 33 Montagu Square have been listed Grade II on the National Heritage List for England since December 1987.Joseph T. Parkinson designed and built the houses in Montagu Square as part of the Portman Estate, between 1810 and 1815.