From the Wikipedia page 
Staple Inn is a building on the south side of High Holborn in London. Located near Chancery Lane Station, it is used as the London office of the Institute of Actuaries and is the last surviving Inn of Chancery and is a listed building.
It was originally attached to Gray's Inn, which is one of the four Inns of Court. The Inns of Chancery fell into decay in the 19th century. All of them were dissolved, and most were demolished. Staple Inn is the only one which survives largely intact.
Staple Inn dates from 1585. The building was once the wool staple, where wool was weighed and taxed. It survived the Great Fire of London, was extensively damaged by a Nazi German Luftwaffe aerial bomb in 1944, but was subsequently restored. It has a distinctive timber-framed façade, cruck roof and an internal courtyard.
The historic interiors include a great hall. Much of the building is used by the Institute of Actuaries. The ground floor street frontage is let to shops and restaurants who are required to use quieter signage than they do on less sensitive buildings.