SAN FRANCISCO — With a new head of office in San Francisco, Duane Morris has plans to expand its footprint in Northern California.

The San Francisco office, opened in 1998, is the firm’s third largest with about 50 attorneys stationed at the post. Another 20 split their time between San Francisco and another West Coast office. But John Soroko, the firm’s chairman, says there’s still room for growth. Litigation partner Stephen Sutro has been appointed to lead the charge.