One San Francisco-specific building code that might make it difficult to subdivide an office building into smaller rooms is SFBC 1204 https://codelibrary.amlegal.com/codes/san_francisco/latest/s... that requires almost all habitable rooms to have a window for natural light. In San Francisco, we trust mechanical ventilation, but for some reason we don’t trust electric lights. I think this code is an obsolete holdover that has nothing to do with health or safety anymore.