Facebook is continually expanding in its Silicon Valley hometown of Menlo Park, California. On Friday it signed a lease at 43-story Park Tower in San Francisco, making the social networking giant one of the city’s largest tech tenants.

The social networking giant reached a deal Friday to take all the office space at the newly constructed Park Tower at Transbay. It’s the second big step into the city for Facebook following an agreement last year of another new tower at 181 Fremont.

According to MetLife Investment Management, one of the owners of Park Tower, the Menlo Park Company agreed to rent 755,900 square feet of office space.

John Tenanes, Facebook’s Vice President of global facilities and real estate said in an emailed statement that they look forward to joining the San Francisco community. “This new space will support our growing workforce as we continue to attract strong talent.”

The move comes as Facebook and other tech companies are not headquartered in San Francisco and have opened offices there to help recruit workers who do not want to commute to the South Bay or Peninsula. Microsoft Corp.’s LinkedIn and Alphabet Inc.’s Google are among the firms that have taken space in San Francisco and thus smaller companies are increasingly finding it difficult to operate in the Bay Area, where Facebook and Google are snapping up office space.

Last week, Facebook-owned Instagram moved into 181 Fremont Street, just a three-minute walk from Park Tower, which is at 250 Howard Street. Yet there are no details to share about which teams would be at Park Tower said Facebook spokesman Jamil Walker.