| # | Company | Employees |
|---|---|---|
| 1 |
The Ohio State Universityosu.edu
Large public university offering extensive research opportunities and multiple regional campuses, serving as a model for Ohio's higher education system. |
30,775 |
| 2 |
University of Cincinnatiuc.edu
Public research university combining academic excellence with cooperative education, producing impactful discoveries and significant regional economic contributions. |
16,727 |
| 3 |
The Ohio State University Wexner Medical Centerwexnermedical.osu.edu
Academic medical center providing personalized patient care, medical education, research innovation, and extensive healthcare services across multiple specialties. |
15,993 |
| 4 |
Nationwide Children's Hospitalnationwidechildrens.org
Provides advanced pediatric medical care, conducts leading research, trains specialists, and offers specialized programs in heart, cancer, and neonatology. |
12,575 |
| 5 |
Ohio Universityohio.edu
Public university offering extensive undergraduate and graduate programs, recognized for research, academic quality, and character-building initiatives. |
9,763 |
| 6 |
Kent State Universitykent.edu
A top-tier research university offering diverse academic programs, award-winning student support services, and global opportunities for students and alumni |
8,986 |
| 7 |
Case Western Reserve Universitycase.edu
Leading research university offering nationally recognized programs in arts, sciences, engineering, medicine, law, business, and social sciences in Cleveland. |
8,529 |
| 8 |
Battellebattelle.org
A science and technology company solving critical issues through research, development, manufacturing, and services for government and commercial clients worldwide |
6,013 |
| 9 |
The University of Akronuakron.edu
Public research university offering diverse degree programs with career-focused, experiential learning, internships, research, and support for various student groups. |
5,347 |
| 10 |
Cleveland State Universitycsuohio.edu
Established in 1964, this urban research university offers over 200 academic programs to 17,000+ students and is recognized as one of America's Best Colleges |
4,317 |
| 11 |
Air Force Research Laboratoryafresearchlab.com
Leading discovery, development, delivery of warfighting technologies for air, space, cyberspace forces, providing unmatched advantage through research, technology, and strategic partnerships. |
3,085 |
| 12 |
Ohio State University Comprehensive Cancer Center-James Cancer Hospital & Solove Research Institutecancer.osu.edu
Leading cancer research center and hospital focused on integrating research, education, and patient care to advance prevention, detection, and treatment Ranked among top in the nation |
1,970 |
| 13 |
NASA Glenn Research Centernasa.gov
The company is a NASA center near Cleveland with world-class facilities for aerospace research and testing, essential to the agency and regional economy |
1,775 |
| 14 |
Case Western Reserve University School of Medicinecase.edu
Leading medical school with innovative education, groundbreaking research, creating physicians, scientists, and healthcare professionals, and advancing community healthcare globally and locally |
1,540 |
| 15 |
University of Cincinnati College of Medicinejobs.uc.edu
The company provides medical education programs, conducts research, and offers clinical care through its faculty practice group |
1,197 |
| 16 |
Northeast Ohio Medical University (NEOMED)neomed.edu
Specializing in interprofessional training, the company prepares future healthcare leaders, educates aspiring physicians, and shares the NEOMED journey through various initiatives |
1,117 |
| 17 |
Central State Universitycentralstate.edu
Established in 1887, a prestigious academic institution focused on increasing baccalaureate degree holders, with expertise in emerging technologies and fine arts |
917 |
| 18 |
University of Dayton Research Instituteudayton.edu
A national leader in scientific and engineering research providing innovative solutions in materials, energy, aeropropulsion, and more with integrity and commitment |
855 |
| 19 |
The Ohio State University College of Medicinemedicine.osu.edu
A leading academic medical center offering innovative programs, training healthcare professionals, conducting cutting-edge research, and providing unique therapies to patients |
852 |
| 20 |
U.S. Air Force Institute of Technologyafit.edu
A leading institution for defense-focused graduate education and research, specializing in aerospace, space, and cyber forces technology, located at Wright-Patterson AFB |
694 |
| 21 |
Ohio University Heritage College of Osteopathic Medicineohio.edu
A leader in training primary care physicians and specialists, providing education programs, clinical experiences, and research opportunities across three campuses |
520 |
| 22 |
The Ohio State University College of Engineeringengineering.osu.edu
The company is an engineering college that offers hands-on learning, team-based projects, and a variety of engineering and architecture programs |
510 |
| 23 |
University of Cincinnati - College of Engineering and Applied Scienceceas.uc.edu
The College of Engineering & Applied Science offers undergraduate and graduate degree programs with a focus on excellence in education, research, and community knowledge transfer |
509 |
| 24 |
University of Cincinnati Carl H. Lindner College of Businessbusiness.uc.edu
Developing future business leaders through personalized career coaching and experiential learning, with a focus on innovation and cutting-edge research in various academic areas |
508 |
| 25 |
Cleveland Clinic Researchlerner.ccf.org
Global research organization collaborating with physicians to translate laboratory discoveries into advanced patient care within an international hospital system. |
471 |
| 26 |
The University of Toledo College of Medicine and Life Sciencesutoledo.edu
The University of Toledo College of Medicine and Life Sciences educates clinicians and scientists, provides high-quality patient care, and conducts nationally recognized research |
412 |
| 27 |
The Ohio State University College of Arts and Sciencesartsandsciences.osu.edu
The College of Arts and Sciences at The Ohio State University offers academic programs in undergraduate and graduate education and research |
398 |
| 28 |
The Ohio State University College of Dentistrydentistry.osu.edu
Provides dental patient care, trains specialists, conducts research in various dental fields, and offers extensive community outreach programs. |
372 |
| 29 |
The Ohio State University College of Veterinary Medicinevet.osu.edu
A leading veterinary college offering innovative clinical services, research opportunities, and education for students, clinicians, and researchers |
357 |
| 30 | 327 | |
| 31 |
Hebrew Union Collegehuc.edu
We are a leading institution preparing individuals for leadership roles in Jewish life, education, nonprofit work, and academia worldwide |
317 |
| 32 |
Parallax Advanced Researchparallaxresearch.org
A nonprofit research institute focused on solving national security and prosperity challenges by collaborating with government, industry, and academia for innovation |
186 |
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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 Nov 2, 2026.
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