Complex sentence: Most of Mount Sutro remains private property owned by the University of California, San Francisco (UCSF), but a parcel, including the summit, has been set aside as the Mount Sutro Open Space Reserve and is open to the public.
Split into simpler sentences: Most of Mount Sutro is owned by the University of California, San Francisco (UCSF). A parcel, including the summit, is protected as the Mount Sutro Open Space Reserve by UCSF, and open to the public.