| # | Company | Employees |
|---|---|---|
| 1 |
University of Californiajobs.universityofcalifornia.edu
Educating top minds, advancing research, engaging communities, supporting economy, improving health, protecting environment, and driving innovation across California. |
152,503 |
| 2 | 29,540 | |
| 3 |
Stanford Universitystanford.edu
Leading research university fostering innovation, education, and global citizenship with extensive resources, diverse programs, and strong community partnerships. |
28,573 |
| 4 |
University of California, Berkeleyberkeley.edu
Public research university offering diverse academic programs, fostering innovation, and serving as a flagship institution in California. |
24,082 |
| 5 |
University of Southern Californiausc.edu
A leading private research university located in Los Angeles, focused on academic excellence and fostering a community of alumni and students |
23,894 |
| 6 |
UC San Diegoucsd.edu
A globally renowned research university fostering collaboration, driving discoveries, and equipping students to solve pressing global issues as changemakers |
22,205 |
| 7 |
University of California, San Franciscoucsf.edu
The company is dedicated to achieving breakthroughs through top research, education, and patient care, emphasizing collaboration across disciplines |
21,833 |
| 8 |
University of California, Davisucdavis.edu
Public university offering diverse undergraduate and graduate programs, conducting extensive research, fostering innovation, and preparing future leaders across multiple disciplines. |
21,439 |
| 9 | 14,695 | |
| 10 |
City of Hopecityofhope.org
Comprehensive cancer research, treatment, and innovation with a national network, focusing on breakthrough medicines and patient care integration. |
12,442 |
| 11 |
UC Santa Barbaraucsb.edu
A renowned institution on the California coast, UCSB fosters academic excellence and creativity, showcasing achievements and connecting the Gaucho community |
10,619 |
| 12 |
San Jos茅 State Universitysjsu.edu
Public university in Silicon Valley offering hands-on learning, research, career services, alumni networking, and community engagement opportunities. |
10,329 |
| 13 |
University of California, Santa Cruzucsc.edu
A pioneering university with a focus on social justice, groundbreaking research, and a unique academic environment, producing influential alumni worldwide |
9,767 |
| 14 |
San Diego State Universitysdsu.edu
Top-ranked public research institution offering transformative experiences, international opportunities, diversity initiatives, and vibrant campus life for over 36,000 students |
9,764 |
| 15 |
Lawrence Livermore National Laboratoryllnl.gov
Development and application of advanced science, technology, and engineering to enhance national security, counterterrorism, defense, energy, and environmental challenges. |
9,546 |
| 16 |
Stanford University School of Medicinemed.stanford.edu
Premier academic hub combining research, education, and clinical care to advance health through innovation, leadership, and collaborative discoveries. |
9,384 |
| 17 |
NASA Jet Propulsion Laboratoryjpl.jobs
A federally funded research and development center managed by Caltech for NASA, specializing in space exploration, technology development, and scientific problem-solving |
8,652 |
| 18 |
California State University, Fullertonlinktr.ee
Public university providing innovative education, research opportunities, cultural engagement, and athletic programs to support student and community development. |
7,638 |
| 19 |
California State University, Northridgecsun.edu
A vibrant university community in Los Angeles' San Fernando Valley with 40,000 students, 4,000 faculty/staff, and a commitment to education and service |
7,139 |
| 20 |
Caltechcaltech.edu
A leading science and engineering research institution in California focused on seeking answers, discovering new knowledge, and transforming the future |
5,794 |
| 21 |
California State University-Sacramentocsus.edu
An urban university in California with a diverse student body, offering small classes, quality teaching, research, and internship opportunities in government |
5,616 |
| 22 |
Loyola Marymount Universitylmu.edu
Comprehensive university providing undergraduate, graduate, law, and credential programs with a strong Jesuit Catholic tradition and high research activity. |
5,381 |
| 23 |
Berkeley Lablinktr.ee
A national laboratory managed by the University of California for the Department of Energy, focusing on sustainable energy, materials innovation, computing, and scientific exploration |
5,253 |
| 24 |
Stanford University Graduate School of Businessgsb.stanford.edu
The company provides management and leadership programs, including MBA, MSx, PhD, and Executive Education, empowering individuals through innovative learning experiences |
5,192 |
| 25 |
California State University, Los Angelescalstatela.edu
Comprehensive public university offering nationally recognized programs in science, arts, business, and engineering, dedicated to student upward mobility and community public good. |
4,380 |
| 26 |
University of California, Merceducmerced.edu
Leading American research university formed in 2005, known for its sustainable design, economic impact, and commitment to increasing college access |
3,987 |
| 27 |
GIA (Gemological Institute of America)gia.edu
A nonprofit committed to research, education, and innovation in the gem industry, ensuring public trust and promoting sustainability |
3,399 |
| 28 | 2,968 | |
| 29 |
David Geffen School of Medicine at UCLAmedschool.ucla.edu
A leading medical institution focusing on research, education, patient care, and community engagement to advance medicine and benefit society |
2,846 |
| 30 | 2,839 | |
| 31 |
NASA Ames Research Centernasa.gov
A leading research center in Silicon Valley conducting cutting-edge research in aeronautics, exploration technology, and science for over 75 years |
2,464 |
| 32 |
Scripps Researchscripps.edu
A leader in biomedical research, innovation, and education, working to improve human health and create hope for millions worldwide |
2,348 |
| 33 |
SLAC National Accelerator Laboratorywww6.slac.stanford.edu
A diverse workforce of 1,700 employees at the forefront of cutting-edge research in various disciplines, collaborating in a stimulating environment |
2,235 |
| 34 | 2,092 | |
| 35 |
Public Health Institutephi.org
A nonprofit organization dedicated to promoting health and well-being through research and innovations in public health on a national and international scale |
1,646 |
| 36 |
UCLA Anderson School of Managementanderson.ucla.edu
Preparing global leaders with a world view to drive change and make a lasting difference in organizations and communities worldwide |
1,609 |
| 37 |
Keck School of Medicine of the University of Southern Californiakeck.usc.edu
A leading medical school in Los Angeles affiliated with USC, offering diverse patient care experiences and cutting-edge research opportunities |
1,603 |
| 38 |
UC Merceducmerced.edu
Newest campus in the UC system focused on sustainability, research, and supporting underserved students, with a major expansion project underway |
1,563 |
| 39 |
Humboldt State Universityhumboldt.edu
The company, formerly known as Humboldt State University, has archived its LinkedIn page New updates can now be found on Cal Poly Humboldt's page |
1,560 |
| 40 |
Scripps Institution of Oceanographyscripps.ucsd.edu
A world-renowned institution focusing on ocean and earth science research, education, and public service across various disciplines |
1,484 |
| 41 |
Salk Institute for Biological Studiessalk.edu
World-class scientists conducting advanced research in neuroscience, cancer, aging, immunobiology, plant biology, and computational biology fields. |
1,249 |
| 42 |
UC San Diego School of Medicinemedschool.ucsd.edu
Dedicated to advancing understanding and treatment of human diseases through translational research, clinical care, and education for a healthier world |
1,201 |
| 43 |
UC Irvine School of Medicinemedschool.uci.edu
Advancing medical research, educating diverse health professionals, and providing patient-centered healthcare through clinical, teaching, and research programs in Orange County. |
1,119 |
| 44 | 962 | |
| 45 |
UCLA Henry Samueli School of Engineering and Applied Sciencesamueli.ucla.edu
Leading engineering school offering 28 degree programs, conducting cutting-edge research in renewable energy, healthcare, cybersecurity, and more with top-ranked faculty and research centers |
961 |
| 46 |
SDSU Research Foundationfoundation.sdsu.edu
Non-profit organization managing grants, contracts, compliance, and administrative services to support San Diego State University's research and educational objectives. |
951 |
| 47 |
Charles R. Drew University of Medicine and Sciencecdrewu.edu
A private nonprofit medical institution in South Los Angeles, offering education, research, and clinical services to train health professionals for underserved communities |
946 |
| 48 |
University of California, Los Angeles - School of Lawucla.edu
A leading law school with innovative teaching methods, interdisciplinary research, and a focus on connecting research to society and the legal profession |
797 |
| 49 |
California Academy of Sciencescalacademy.org
A renowned scientific and educational institution in San Francisco dedicated to regenerating the natural world through its aquarium, planetarium, and natural history museum |
787 |
| 50 |
Sanford Burnham Prebyssbpdiscovery.org
A renowned biomedical research institute advancing scientific discoveries in cancer, neuroscience, immunology, and children's diseases while focusing on drug discovery and improving human health |
786 |
| 51 |
NASA, Office of Inspector Generalnasa.gov
The company operates the world's largest aerodynamics test facility, specializing in testing aircraft, wind turbines, parachutes, and other large-scale structures for various industries |
750 |
| 52 |
University of California, Berkeley - School of Lawlaw.berkeley.edu
Offers top-tier J.D., LL.M., and J.S.D. programs with expert faculty, committed to solving real-world problems and creating a just society through research and pro-bono efforts. |
715 |
| 53 |
UC San Diego Jacobs School of Engineeringjacobsschool.ucsd.edu
A leading engineering school educating future technology leaders, conducting innovative research, and collaborating across disciplines to tackle global challenges |
656 |
| 54 |
Hoover Institution, Stanford Universityhoover.org
Researching economics, politics, and international affairs to advance ideas promoting economic opportunity, prosperity, and securing peace for America and humanity. |
652 |
| 55 |
UC Davis Weill School of Veterinary Medicinevetmed.ucdavis.edu
This company focuses on advancing animal, human, and environmental health through veterinary education, research, clinical services, and public outreach programs in California |
619 |
| 56 |
Gladstone Institutesgladstone.org
The company drives discovery in disease-oriented science, mentors future leaders, and explores innovative approaches to overcome health challenges through convergence |
596 |
| 57 |
The Lundquist Institutelundquist.org
Conducts groundbreaking medical research, collaborating with Harbor-UCLA Medical Center to translate discoveries into treatments benefiting individuals across various health conditions |
586 |
| 58 |
Internet Archivearchive.org
non-profit digital library providing free access to billions of web pages, books, audio, video, images, and software archives. |
313 |
| 59 |
UC Berkeley College of Computing, Data Science, and Societycdss.berkeley.edu
A leading academic institution offering a dynamic teaching and research environment in data science, preparing students to address social challenges across domains |
205 |
| 60 |
Stanford Mussallem Center for Biodesignbiodesign.stanford.edu
Dedicated to advancing health outcomes and equity through innovation education, translation, and policy, reinventing healthcare with technology for a healthier world |
174 |
| 61 |
huMannity Medtechumannitymedtec.org
Non-profit organization pioneering life-enhancing medical technologies for undermet healthcare needs, focusing on long-term, high-risk challenges with talented staff |
144 |
| 62 | 75 | |
| 63 |
Sarafan ChEM-H | Stanford Universitychemh.stanford.edu
Innovative hub focused on improving human health through diverse disciplines and people in life, physical, and clinical sciences |
51 |
| 64 |
Stanford Research Institutesri.com
Independent nonprofit research institute conducting client-sponsored R&D for various organizations, bringing innovations to the marketplace through licenses and new ventures |
24 |
| 65 |
Laboratory for the Chemistry of Construction Materials (LC2)lcc-ucla.com
The company conducts research to develop sustainable, low-carbon materials for infrastructure construction, focusing on improving concrete performance while promoting environmental responsibility |
3 |
Turn this list into pipeline
Tamtam finds the decision-makers at every company on a list like this one, with verified emails, phone numbers and the buying signals that tell you when to reach out.
How this list is built
Every company on this list has a Tamtam company profile. The industry is the one the company gives on LinkedIn; categories such as SaaS or fintech are classified by Tamtam's AI from the company's website and LinkedIn page; and the headquarters city must match the company's own address. Companies are ranked by the number of employees on LinkedIn, and the list is refreshed every night. Classifications can be wrong, so treat the list as a starting point rather than an official ranking. Last updated Oct 24, 2026.
More company lists in California
- The largest companies in California 12,813
- SaaS companies in California 1,617
- Software Development companies in California 1,386
- Venture capital and private equity firms in California 786
- IT Services and IT Consulting companies in California 730
- Venture Capital and Private Equity Principals companies in California 645
- AI companies in California 606
- AI-native companies in California 552
- Retail chains in California 527
- Hospitals and Health Care companies in California 519
- Financial Services companies in California 513
- Financial services firms in California 503
- Education providers in California 498
- IT services companies in California 428
- Manufacturers in California 417
- Technology, Information and Internet companies in California 413
- Higher Education companies in California 376
- Public sector organisations in California 337
- Hardware manufacturers in California 335
- Critical infrastructure operators in California 293
- Government Administration companies in California 279
- Healthcare providers in California 277
- Education Administration Programs companies in California 277
- Real Estate companies in California 275