In a release, Steve Durels, EVP and director of leasing and real property at the office REIT, says "Ambassador has been a long-term building tenant and we're delighted that they have chosen to extend that relationship." The renewal by Ambassador, an interior construction company, increases the occupancy at the 485,641-square-foot 317 Madison to 98%.

James E. Frederick of Colliers ABR represented Ambassador in the 317 Madison transaction, while SL Green's Elaine Anazagasty acted in-house on behalf of the landlord. Other tenants at 317 Madison, which SL Green bought from Richfield Investment Trust for $105.6 million in 2001, include TD Bank, Entertainment Software Board, Headway Corporate Resources and New York Focus.

Financial consulting and accounting firm BDO Seidman formerly occupied the space at 330 Madison Ave. before moving last summer to SL Green's 100 Park Ave., where it now occupies 121,441 square feet as the anchor tenant. SL Green Leasing EVP Howard Tenenbaum, who represented both Horizon and landlord Vornado with his colleague Gary Rosen, says in a release that the deal represents "a tremendous economic solution for Horizon Media, providing them with fully furnished, upscale space to accommodate their ongoing growth." Horizon is said to be the largest independent media services company in the country, and reportedly has already moved into the 330 Madison space. Its New York headquarters are located at 630 Third Ave.