How much for the antennas atop Hancock Center?

A Boston-based investor that specializes in broadcast and wireless towers has paid $70 million for the antennas atop the John Hancock Center, another step in a plan by the skyscraper's owners to sell off the building's parts piecemeal.

An affiliate of American Tower Corp. closed in late October on the 34,000 square feet of rooftop space housing TV and radio transmission equipment, county records show. American Tower bought the property from a joint venture of Deutsche Bank A.G. and NorthStar Realty Finance Corp., which seized the landmark tower earlier this year after its prior owner, a joint venture led by a Goldman Sachs Group Inc. unit, defaulted on about $400 million in debt. Leased by TV networks, FM radio stations and governments, the Hancock's antennas are second only to the Willis Tower's in a city with limited broadcast capacity, according to David Denton, co-founder of Florida-based Tall Tower Ventures LLC. About nine FM stations in the Chicago market use the Hancock for their primary operations, while most TV stations use it as a backup site and operate from Willis, he said.