SAN JOSE — The Platform 16 tech campus project, slated to become a striking office complex perched on the banks of the Guadalupe River in downtown San Jose, is now fully owned by one of the nation’s biggest and most successful developers.

Boston Properties has bought out its two partners in the Platform 16 development, according to Santa Clara County public documents filed on Feb. 20.

A group led by San Francisco-based TMG Partners and San Jose-based Valley Oak Partners has sold its ownership interest to an affiliate of Boston Properties, the county records show.

In January 2019, Boston Properties came on board as one of the principal owners of the Platform 16 site, joining the owners at the time, TMG and Valley Oak.

TMG and Valley Oak had originally teamed up to buy numerous parcels needed for the land where the office campus would sprout, and also guided the project through a multi-faceted city approval process.

The Platform 16 project is bounded by Autumn Parkway, West Julian Street, North Autumn Street, and a railroad line, and is just south of a Target store that’s part of the bustling San Jose Market Center.

The development also is on the edge of neighborhoods where Google has collected numerous properties for a future transit-oriented development called Downtown West that would rise near the Diridon train station and SAP Center.

“At the site of one of the biggest technology hubs in the country, Platform 16 will help companies attract and retain the best and brightest minds to the area,” Bob Pester, a Boston Properties executive vice president, said at the time of Boston’s move to join the development.

The 1.1-million-square-foot Platform 16 project would consist of three office buildings that will feature 16 terraces where office workers could hold meetings, work on projects, or enjoy leisure time.

The affiliate controlled by Boston Properties, which is based in New England’s largest city, paid $134.75 million in cash for the stakes that the TMG and Valley Oak firms had owned, the county documents show.

The next major steps for the Platform 16 project: construction, leasing, and marketing of the massive development. Boston Properties and TMG Partners will be co-developers of the project, even though TMG and Valley Oak have sold their ownership interests.

CBRE commercial real estate agents Sherman Chan, Mark Schmidt, Mike Charters, and Will Schmidt have begun to scout for one or more tenants at Platform 16.

The developer has been busy clearing away older buildings and other structures on the property to prepare it for the new campus project.

“Platform 16 will offer easy access to public transportation, housing, culture, food, and entertainment in the heart of San Jose,” Pester said.