Twitter co-founders move Obvious Corp into spacious new digs

Biz Stone, co-founder of Twitter, speaks at the Charles Schwab IMPACT 2010 conference in Boston, Massachusetts October 28, 2010.

SAN FRANCISCO (Reuters) - Evan Williams and Biz Stone, the co-founders of Twitter, have leased three sprawling floors in a historic downtown San Francisco tower for their low-profile start-up incubator, The Obvious Corporation.

Obvious said Friday it leased 75,000 square feet at the busy 760 Market Street location - known as the Phelan Building - in one of the city's larger commercial real estate deals in recent months.

The downtown space will be able to hold roughly 500 employees and signals ambitions at Obvious, which was re-constituted when Williams and Stone both left Twitter in 2011.

The incubator, with no more than two dozen employees, has mostly stayed out of the press except when it unveiled two new blogging platforms called Medium and Branch last September.

Although still thinly staffed, Obvious's new space is larger than start-up Pinterest's recently inked lease in the city.

"We need the right space from which to grow the Medium team and position Obvious to focus on bringing our new ideas to life," Obvious CEO Williams said in a statement Friday about the new lease.

The company will occupy the seventh, eighth and ninth floors of the triangular building, which wraps around a central courtyard, said Jenny Haeg, a real estate agent who has brokered leases for Square Inc, Dropbox, Airbnb and other large tech startups. (Reporting by Gerry Shih; Editing by Bob Burgdorfer)