The virtual IT system provider will occupy level 31 in the landmark City of London office building.
Ipsoft had signed a ten-year lease with a break option after five.
Level 31 of The Leadenhall Building offers 11,475 sq ft of office space; Informally known as “The Cheesegrater” because of its distinctive wedge shape it was developed by British Land and Oxford Properties.
At 224 meters high it is the tallest building in The City, including 46 floors of office space.
IPsoft was represented by Cushman & Wakefield.
JLL and DTZ advised Oxford Properties and British Land.