A team of San Fran­cis­co Chron­i­cle reporters—Susie Neil­son, Emma Stiefel, J.K. Dineen, and Lau­ren Hepler—conducted an in-depth analy­sis of the Bay Area’s prop­er­ty own­er­ship records to trace the real own­er­ship of the region’s rental prop­er­ties.

“Cal­i­for­nia does­n’t have hard-and-fast rules on how prop­er­ty own­ers iden­ti­fy them­selves; large cor­po­ra­tions, hedge funds and even wealthy fam­i­lies often pur­chase mul­ti­ple homes through shell com­pa­nies or trusts, shield­ing their names from own­er­ship records.” To get more clar­i­ty, the team “used machine learn­ing meth­ods to parse the data and called on dozens of experts and addi­tion­al data sources” to nar­row down the 12 most influ­en­tial prop­er­ty own­ers in the region. Accord­ing to the authors, “We believe this is an unprece­dent­ed effort to uncov­er rental own­er­ship and man­age­ment net­works across all nine coun­ties in the region: Alame­da, Con­tra Cos­ta, Marin, Napa, San Fran­cis­co, San Mateo, San­ta Clara, Solano and Sono­ma.”

The arti­cle lists the 12 own­ers and details about their prop­er­ties, busi­ness prac­tices, the demo­graph­ics of their ten­ants, the geo­graph­ic range of each own­er’s prop­er­ties, infor­ma­tion about inspec­tions and safe­ty vio­la­tions, evic­tion prac­tices, and more. The authors note that “Even if the own­er of your prop­er­ty isn’t on our list, you can learn more about who owns it by using our map of near­ly 2.3 mil­lion Bay Area prop­er­ties here.”