Wateridge Plaza in Sorrento Mesa (photo courtesy of Parallel Capital Partners)

Wateridge Plaza in Sorrento Mesa (photo courtesy of Parallel Capital Partners)

Investment company Parallel Capital Partners Inc. of San Diego has bought Wateridge Plaza, a three-building office campus in Sorrento Mesa, for $72.5 million.

The purchase was made through a joint venture, company officials said, with Chicago-based Equity Group Investments, founded by entrepreneur Sam Zell. The seller was a partnership of Boston-based Beacon Capital Partners and C-III Realty, represented by Adam Edwards of Eastdil Secured.

The campus is at 10201, 10221 and 10241 Wateridge Circle. It consists of three five- and six-story buildings, totaling 278,787 square feet, with a parking complex.

Officials said the 8-acre property includes future development potential of about 168,000 additional square feet of office space. The complex was built in 1985 and renovated in 2012; it is 72 percent occupied.

The prior owners invested $14 million in upgrades from 2009 to 2013, and the new owners plan additional capital improvements. Parallel has retained architectural firm Gensler and Glanz Signing & Graphics to plan and implement upgrades.

Parallel is led by principals Matt Root, Jim Ingebritsen and Jim Reynolds. The privately held company made more than $400 million in commercial real estate acquisitions last year, with key purchases in Dallas and Orange County.

The investment firm now owns 13 office, industrial and related properties in the San Diego market, with much of its local portfolio concentrated in Sorrento Mesa and Sorrento Valley.