DivcoWest of San Francisco, which has been aggressively buying and selling office buildings in Boston during the post-recession recovery, is getting into the development game with its purchase of Cambridge’s long-delayed NorthPoint mixed-use project for $291 million.

The former rail yard has gone through a series of ownership changes over the last decade as developers attempt to build out the 42-acre site with 4.5 million square feet of commercial and residential development. It was most recently acquired in 2010 by Canyon-Johnson Urban Funds, a group led by NBA Hall of Famer Magic Johnson, in a partnership with Boston-based HYM Investment Group.

DivcoWest, which has an East Coast office in Kendall Square, has acquired more than 4.6 million square feet of commercial space in Greater Boston. The company’s acquisition strategy focused on the region’s potential growth in tech employment and its upward pressure on office rents. Through a joint venture with Synergy Investments of Boston, it acquired 327-335 Summer St. in Fort Point in 2013, a building which is being renovated for the expanded headquarters of cloud computing company LogMeIn.

In January, DivcoWest acquired the 670,000-square-foot One Kendall Square campus in Cambridge for $395 million. During the same month it sold the Necco Street garage in Boston’s Fort Point for $56 million, less than two years after acquiring it for $34 million. It also sold a nine-building portfolio of office and medical buildings in Fort Point and South End for $250 million.

In 2014, its local acquisitions included 71, 77 and 87 Summer St. for $31.5 million, 38 Chauncy St. for $39.5 million and 55 Summer St. for $48 million, all in joint ventures with Boston-based Synergy Investments.

NorthPoint has approvals to build 2.4 million square feet of residential and 2.1 million square feet of commercial space. The 355-unit Twenty 10 luxury rental tower opened in June.

Earlier this year, Cambridge officials amended the NorthPoint zoning to double the amount of retail space to 300,000 square feet, including a supermarket up to 50,000 square feet.

“In order to make it a vibrant community, there needs to be a great retail component as well,” HYM Investments Thomas O’Brien told Banker & Tradesman in March. “We already have the CambridgeSide Galleria right around the corner that has national chains. What’s needed now is more retail that’s local in character, more Cambridge-like.”