Boston Properties is teaming up with TMG Partners to develop a 1.1-million-sq.-ft. urban office campus in downtown San Jose. : (Bloomberg)—Boston Properties Inc. is increasing its investment in California’s Silicon Valley with a new office development that could attract some of the biggest names in technology. The company is teaming up with San Francisco-based TMG Partners to develop Platform 16, a 1.1 million-square-foot (102,000-square-meter) urban campus in downtown San Jose that will have 16 outdoor terraces, a gym and a conference center.