Between 1999 and 2004 the San Francisco Airport Commission operated city - owned SFO Enterprises , Inc. , to oversee its business purchases and operations of ventures .
SFO is owned and policed by the City and County of San Francisco , but is in San Mateo County .
Between 1999 and 2004 the San Francisco Airport Commission operated city - owned SFO Enterprises , Inc. , to oversee SFO 's business purchases and operations of ventures .
SFO is owned and policed by the City and County of San Francisco , but is in San Mateo County .