| Southern California Permanente Medical Group | Redlands | 11,293 |
| Permanente Medical Group Inc | Oakland | 10,996 |
| Sutter Bay Medical Foundation | Fremont | 3,829 |
| Stanford Health Care | Stanford | 3,122 |
| Sutter Valley Medical Foundation | Modesto | 2,500 |
| Regents of the University of California | San Diego | 2,089 |
| University of California San Francisco | San Francisco | 1,839 |
| Cedars-Sinai Medical Care Foundation | West Hollywood | 1,692 |
| UCSF Medical Group Business Services | San Francisco | 1,598 |
| Regents of the Univ of Ca | Sacramento | 1,584 |
| Providence Medical Foundation | Victorville | 1,466 |
| The Regents of the University of California | Santa Monica | 1,462 |
| Scripps Health | La Jolla | 1,433 |
| Usc Care Medical Group Inc | Los Angeles | 1,380 |
| Faculty Physicians and Surgeons of Llusm | Loma Linda | 1,315 |
| Cep America - California | Pomona | 1,292 |
| Dignity Health Medical Foundation | Folsom | 1,184 |
| Galen Inpatient Physicians PC | Hanford | 1,077 |
| County of Santa Clara | San Jose | 1,022 |
| City of Hope Medical Foundation | Duarte | 982 |
| Sharp Rees-Stealy Medical Group Inc | San Diego | 884 |
| Cep America - Anesthesia PC | Redding | 849 |
| Cedars-Sinai Medical Center | West Hollywood | 799 |
| California Luna Care Physical Therapy PC | Los Gatos | 780 |
| Healthcare Partners Affiliates Medical Group | Anaheim | 754 |
| Regents of the University of California | San Francisco | 732 |
| Pacific Coast Psychiatric Associates Inc | Encinitas | 662 |
| Adventist Health Physicians Network | Saint Helena | 628 |
| Pih Health Physicians | Santa Fe Springs | 622 |
| Alameda Health System | Oakland | 601 |
| University of California Sfgh Medical Group | San Francisco | 587 |
| Sud Specialty Group - Ca | Santa Clara | 568 |
| Regents of the University of California | Sacramento | 567 |
| Memorialcare Medical Foundation | Long Beach | 566 |
| Community Health Partners | Clovis | 504 |
| John Muir Physician Network | Pleasant Hill | 494 |
| Hoag Clinic | Newport Beach | 460 |
| Eisenhower Medical Center | Palm Springs | 456 |
| Emergency and Acute Care Medical Corporation | La Mesa | 422 |
| University Anesthesia Medical Group | San Francisco | 408 |
| County of Los Angeles | Wilmington | 397 |
| Providence Facey Medical Foundation | Valencia | 385 |
| Inpatient Specialists of California PC | Oakdale | 385 |
| Smi Imaging LLC | Beverly Hills | 384 |
| City and County of San Francisco | San Francisco | 365 |
| Monica Perlman MD Inc | San Diego | 364 |
| Orthopaedic and Neurological Rehab Inc | Laguna Woods | 360 |
| County of Ventura | Ventura | 344 |
| Exer Medical Corporation | Highland | 340 |
| Lpch Medical Group Div of Lucile | Palo Alto | 337 |
| Carbon Health Medical Group of California PC | Whittier | 334 |
| Enloe Medical Center | Chico | 333 |
| One Medical Group Inc | San Jose | 331 |
| Beverly Radiology Medical Group III | Corona | 328 |
| University Healthcare Alliance | Pleasanton | 327 |
| Northbay Physicians Surgery Center, LLC | Fairfield | 324 |
| Sansum Clinic | Santa Barbara | 320 |
| Uc Regents | Orange | 319 |
| Family Health Centers of San Diego Inc | San Diego | 311 |
| County of San Mateo | San Mateo | 310 |
| Torrance Health Association Inc | Redondo Beach | 299 |
| Centro de Salud de la Comunidad de San Ysidro,inc. | San Diego | 297 |
| Childrens Hospital Los Angeles Medical Group Inc | Los Angeles | 295 |
| Bass Medical Group | Chico | 291 |
| Community Foundation Medical Group | Fresno | 283 |
| Regents Univ of California UCSF | San Francisco | 283 |
| Los Angeles County Department of Mental Health | Gardena | 282 |
| Providence Saint Johns Medical Foundation | Santa Monica | 281 |
| Department of State Hospitals | Napa | 270 |
| Kern County Hospital Authority | Bakersfield | 266 |
| Central California Faculty Medical Group Inc | Fresno | 265 |
| Svmhs Clinics | Salinas | 259 |
| Pacific Central Coast Health Centers | Templeton | 253 |
| Beaver Medical Group P C | Redlands | 247 |
| Anesthesia Service Medical Group | San Diego | 246 |
| Prohealth Partners, A Medical Group | Long Beach | 239 |
| Regents of the University of | Orange | 239 |
| Regents of the University of California | Santa Monica | 236 |
| Genesis Healthcare Partners PC | San Francisco | 228 |
| Sac Health System | San Bernardino | 227 |
| UCSF Dept of Surgery | San Francisco | 215 |
| Scripps Health Inpatient Providers Medical Group Inc | San Diego | 214 |
| Northbay Health Medical Foundation | Fairfield | 213 |
| Desert Advanced Imaging Medical Center | Palm Springs | 208 |
| Martin Luther King Jr Community Medical Foundation | Compton | 206 |
| El Camino Health Medical Network LLC | Los Gatos | 202 |
| UCLA Radiology Medical Group | Thousand Oaks | 202 |
| County of San Joaquin | French Camp | 199 |
| County of Riverside | Indio | 193 |
| Mdrs Spine and Sport Inc | Temecula | 192 |
| Allied Anesthesia Medical Group Inc | Orange | 191 |
| California Rehabilitation and Sports Therapy A California Physical the | Mission Viejo | 188 |
| County of Monterey | Salinas | 185 |
| All Care Physical Therapy, PC | Long Beach | 185 |
| Community Memorial Health System | Oxnard | 185 |
| Health Diagnostics of California A Professional Corporation | Irvine | 183 |
| Golden State Orthopedics and Spine | Campbell | 182 |
| Mark David Levine MD Professional Corporation | Riverside | 181 |
| Ehab Yacoub MD Inc | Gardena | 181 |
| Sokyahealth Medical Group PC | San Diego | 181 |