| # | Company | Employees |
|---|---|---|
| 1 |
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 |
| 2 |
OpenAIopenai.com
An AI research and deployment company focused on creating safe and beneficial general-purpose artificial intelligence for the benefit of humanity |
9,268 |
| 3 |
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 |
| 4 |
X, The Moonshot Factoryx.company
A moonshot factory inventing and launching breakthrough technologies to create a radically better world |
3,149 |
| 5 | 2,968 | |
| 6 |
Scripps Researchscripps.edu
A leader in biomedical research, innovation, and education, working to improve human health and create hope for millions worldwide |
2,348 |
| 7 |
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 |
| 8 |
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 |
| 9 |
IEEE Computer Societycomputer.org
Facilitating professional development and collaboration in computer science and engineering through conferences, publications, training, and resources for industry advancement |
1,443 |
| 10 |
Samsung Strategy and Innovation Center
A technology innovation center fostering disruptive technologies, investing in startups, and expanding business lines through partnerships and acquisitions |
1,283 |
| 11 |
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 |
| 12 |
WestEdwested.org
A national nonprofit agency promoting equity and excellence in education through research, development, and services, offering professional growth and benefits |
1,237 |
| 13 |
AI at Metaai.meta.com
Advancing AI through open science and collaboration, focusing on infrastructure, NLP, generative AI, vision, and human-computer interaction. |
1,101 |
| 14 | 962 | |
| 15 |
HRL Laboratories, LLChrl.com
Leading research laboratory focused on groundbreaking technology solutions in circuitry, computing, materials, and data extraction for diverse applications in aerospace, automotive, and consumer products |
860 |
| 16 |
Eurofins | EAG Laboratorieseag.com
A scientific services company specializing in advanced materials and integrated circuitry analysis, offering problem-solving expertise to accelerate innovation and ensure quality and compliance |
818 |
| 17 |
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 |
| 18 | 591 | |
| 19 |
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 |
| 20 |
Toyota Research Institutetri.global
The company focuses on advancing AI, automated driving, robotics, and materials science to create safer vehicles and improve mobility for all |
474 |
| 21 |
La Jolla Institute for Immunologylji.org
A non-profit medical research institute dedicated to studying the immune system, discovering causes of disorders, and finding treatments for human diseases |
423 |
| 22 |
Berkeley Artificial Intelligence Researchbair.berkeley.edu
A research lab at UC Berkeley focused on artificial intelligence, machine learning, computer vision, robotics, and interdisciplinary collaborations |
421 |
| 23 |
SETI Instituteseti.org
A Silicon Valley-based nonprofit research organization studying life and intelligence in the universe, promoting diversity, equity, and inclusion |
344 |
| 24 |
BLOCK Development
A research and development facility within a group of companies, established in 2004 and now operating as a subsidiary |
318 |
| 25 |
USC Information Sciences Instituteisi.edu
A leading research institute specializing in advanced information processing, computer, and communication technologies, affiliated with the University of Southern California |
284 |
| 26 | 236 | |
| 27 |
Honda Research Institute USA, Inc.usa.honda-ri.com
An innovative research institute focused on creating technologies and solutions to benefit society through real-world applications |
234 |
| 28 | 222 | |
| 29 |
Brain Exercise Initiativebrainexerciseinitiative.com
Student-run nonprofit helping seniors with dementia remember and thrive through specialized programs and services |
193 |
| 30 | 190 | |
| 31 |
Scientific Applications & Research Associates (SARA), Inc.sara.com
Innovative team specializing in wave energy technology, electromagnetism, acoustics, electronics, and processing for defense, renewable energy, robotics, and testing challenges |
187 |
| 32 |
Midjourneymidjourney.com
An independent research lab pushing boundaries in thought and creativity to enhance human imagination and explore new mediums |
184 |
| 33 |
ProSciento, Inc.prosciento.com
Specializing in metabolic diseases research, we offer customized services for multinational clinical trials to advance drug and device development Visit wwwproscientocom for more information |
180 |
| 34 |
Children's Oncology Groupchildrensoncologygroup.org
World's largest childhood and adolescent cancer research organization, conducting clinical trials to improve treatments and increase survival rates for children with cancer |
174 |
| 35 |
Hawthorne Health, Inc.hawthornehealth.com
Revolutionizing clinical trials by bringing them directly to patients through a network of healthcare professionals, improving data quality and patient experience |
173 |
| 36 |
RISArisalabs.ai
The company specializes in creating AI agents to streamline complex workflows in the healthcare industry |
172 |
| 37 |
NCIRE - The Northern California Institute for Research and Education, Inc.ncire.org
Leading nonprofit research institute dedicated to advancing Veterans health research, pioneering new treatments and setting a new standard of care |
166 |
| 38 |
Rancho BioSciencesranchobiosciences.com
International data curation and analysis services for Pharma, Government, and Biotech, with a team of experienced scientists aiming to find cures for diseases |
165 |
| 39 |
Point Blue Conservation Sciencepointblue.org
A non-profit organization dedicated to conserving birds, wildlife, and ecosystems through scientific research, restoration, outreach, and partnerships Headquarters in Petaluma, California |
165 |
| 40 |
Redrobin.redrob.io
Reorganizing global people data to support sales, recruitment, and networking, backed by top VCs and certified as a great workplace. |
164 |
| 41 |
W.M Keck Science Departmentkecksci.claremont.edu
The WM Keck Science Department offers an integrated science curriculum across three colleges, emphasizing interdisciplinary study and research through collaboration |
148 |
| 42 |
Joint Genome Institutejgi.doe.gov
A DOE user facility at Lawrence Berkeley Lab providing advanced genome science capabilities for research in energy and environmental challenges |
146 |
| 43 |
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 |
| 44 |
YTC America Inc. (YTCA)ytca.com
This company is a North American research center focusing on advanced materials, energy technologies, and next-generation vehicle-related information communication technology for global operations |
31 |
| 45 |
Insight Softmax Consultinginsightsoftmax.com
A company specializing in Data Analytics, AI, and Machine Learning to solve business problems for clients such as Autodesk, BMW, and others |
20 |
| 46 |
DLYog Lab Research Services LLCdlyog.com
The company specializes in developing ethically responsible AI applications for enterprises through automation, cloud, and data center solutions |
2 |
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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.
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