These large companies in Maryland are characterized by a strong presence in research and development, particularly in the health and academic sectors. Johns Hopkins Medicine coordinates research, teaching, and patient care for its medical school and health system. The National Institutes of Health is a major public funder of biomedical research, while the University of Maryland is a public research university. Johns Hopkins Applied Physics Laboratory provides technical expertise for national security. McCormick & Company manufactures spices and seasonings, and Under Armour designs performance apparel.
A notable pattern among these organizations is the significant concentration of headquarters in Baltimore. This city hosts Johns Hopkins Medicine, The Johns Hopkins University, Under Armour, and the University of Maryland, Baltimore (UMB). Many of these entities, such as The National Institutes of Health, The Johns Hopkins University School of Medicine, and the National Institute of Standards and Technology (NIST), have long histories, with founding dates ranging from the late 19th to mid-20th centuries.
| # | Company | Employees | |||
|---|---|---|---|---|---|
| 1 |
Johns Hopkins Medicinehopkinsmedicine.org
Coordinates research, teaching, patient care, and related enterprises for the university's School of Medicine and health system, including hospitals and healthcare practices. |
39,325 | |||
| 2 |
The National Institutes of Healthnih.gov
Largest public funder of biomedical research investing billions annually to improve health, reduce illness, and support medical breakthroughs worldwide. |
28,537 | |||
| 3 |
University of Marylandumd.edu
Public research university emphasizing hands-on learning, interdisciplinary collaboration, innovation, entrepreneurship, and global citizenship through diverse academic and research opportunities. |
21,670 | |||
| 4 |
The Johns Hopkins Universityjhu.edu
Leading research university offering diverse academic programs across multiple campuses, fostering innovation and improving lives through education and discovery. |
18,221 | |||
| 5 |
McCormick & Companymccormickcorporation.com
A global leader in flavor, McCormick manufactures and distributes spices, seasonings, and other flavorful products to the food industry worldwide |
14,000 | |||
| 6 |
Under Armourunderarmour.com
Design and develop innovative performance apparel, footwear, and gear focused on enhancing athletes' training, competition, and recovery experiences. |
13,004 | |||
| 7 | 10,652 | ||||
| 8 |
Johns Hopkins Applied Physics Laboratoryjhuapl.edu
University-affiliated research center providing technical expertise, prototyping, research, development, and analysis for national security and scientific challenges. |
7,850 | |||
| 9 |
The Johns Hopkins University School of Medicinehopkinsmedicine.org
Provider of top-ranked medical and graduate programs, clinical fellowships, residencies, basic science research opportunities, and medical art programs with renowned experts |
7,057 | |||
| 10 |
ESAB Corporationesabcorporation.com
A global leader in innovative solutions for fabrication and specialty gas control markets, focusing on continuous improvement and empowering associates worldwide |
5,556 | |||
| 11 |
National Institute of Standards and Technology (NIST)nist.gov
An innovative federal agency advancing measurement science, standards, and technology to promote US innovation and industrial competitiveness |
4,946 | |||
| 12 |
National Security Agencynsa.gov
Provides foreign signals intelligence to policymakers and military forces while securing national security systems and weaponry through advanced cybersecurity and computer operations. |
4,637 | |||
| 13 |
W. R. Gracegrace.com
Supplies catalysts, engineered materials, process technologies, fine chemicals. Industries enhance modern life. Manufactures renewable fuels, pharmaceuticals, food packaging better, faster, smarter. |
4,244 | |||
| 14 |
NASA Goddard Space Flight Centernasa.gov
A major US laboratory developing and operating unmanned scientific spacecraft for NASA's Earth observation, astronomy, planetary science, and astrophysics missions |
4,049 | |||
| 15 |
University of Maryland, Baltimore (UMB)umaryland.edu
A leading public research university in Maryland offering professional schools in health, law, and human services since 1807 |
3,994 | |||
| 16 | 3,785 | ||||
| 17 |
Precision Medicine Groupprecisionmedicinegrp.com
A company founded in 2012 focused on improving the drug development process through technology, data, human expertise, and strategic acquisitions |
3,553 | |||
| 18 |
Sheppard Prattsheppardpratt.org
A leading nonprofit provider of mental health, substance use, special education, and social services through hospital- and community-based resources, prioritizing global mental health care quality |
3,354 | |||
| 19 |
Hugheshughes.com
Provides broadband equipment, services, and network operations to millions of consumers, businesses, and governments worldwide via satellite and multi-transport technologies. |
3,209 | |||
| 20 |
ZeniMax Mediazenimax.com
This company creates and publishes original interactive entertainment content for consoles, PC, handheld/wireless devices, with award-winning video games and acclaimed development studios |
2,992 | |||
| 21 |
Kennedy Krieger Institutekennedykrieger.org
A renowned institute in Baltimore, MD, specializing in improving the lives of children and adolescents with brain, spinal cord, and musculoskeletal disorders |
2,841 | |||
| 22 |
Tenabletenable.com
Exposes and closes cybersecurity gaps, unifies security visibility, insight, and action across the attack surface for organizations globally. |
2,361 | |||
| 23 |
University of Maryland School of Medicinemedschool.umaryland.edu
Leading biomedical research institution with top-tier faculty and extensive global reach, dedicated to advancing innovative research in virology, genomics, and global health |
2,179 | |||
| 24 |
Precision For Medicineprecisionformedicine.com
A global precision medicine clinical research organization improving therapeutics development with integrated clinical operations, laboratory expertise, and advanced data sciences |
2,060 | |||
| 25 |
Thales Defense & Security, Inc.thalesdsi.com
Global provider of innovative solutions for defense, federal, and commercial markets including communication systems, sonar systems, data protection, and technology integration for various domains |
2,013 | |||
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| 26 |
Naval Air Warfare Center Aircraft Division (NAWCAD)navair.navy.mil
Supporting research, development, testing, and sustainment of Navy and Marine Corps aircraft globally, with a workforce of military and civilians Headquarters in Maryland |
1,986 | |||
| 27 |
X-energyx-energy.com
development and manufacturing of innovative nuclear fuel and reactor designs for safe, affordable, and reliable carbon-free baseload power |
1,858 | |||
| 28 |
US Pharmacopeiausp.org
An independent, nonprofit organization establishing quality standards for medicines and dietary supplements to protect patient safety and improve global health |
1,672 | |||
| 29 |
AAI Corporationtextronsystems.com
This company develops and integrates products and services for aerospace, defense, law enforcement, security, and critical infrastructure protection worldwide |
1,655 | |||
| 30 |
US Fertilityusfertility.com
Leader in reproductive medicine and IVF services, supporting physicians and couples in building families through innovative science and advanced technology |
1,604 | |||
| 31 |
University of Maryland Eastern Shoreumes.edu
A historically black university offering accredited degree programs in various fields, research opportunities, and graduate-level programs focusing on teaching and stewardship |
1,588 | |||
| 32 |
Hughes Systique Corporation (HSC)hsc.com
A multinational provider of digital solutions and services, specializing in software development, with expertise in Networking, AI & ML, Retail, Automotive, IoT, Blockchain, and Security |
1,547 | |||
| 33 |
United Therapeutics Corporationunither.com
Biotechnology company developing unique products for patients with chronic conditions, with a focus on providing transplantable organs Employees collaborate worldwide |
1,515 | |||
| 34 |
Emergent BioSolutionsemergentbiosolutions.com
This company develops, manufactures, and delivers protections against public health threats to defend people and ensure preparedness |
1,366 | |||
| 35 |
Medifast, Incmedifastinc.com
Science-based health company offering personalized lifestyle plans, products, and coaching to improve metabolic function and body composition. |
1,321 | |||
| 36 | 1,296 | ||||
| 37 |
Baltimore Aircoil Companybaltimoreaircoil.com
Design and manufacture advanced evaporative, hybrid, and dry cooling technologies for HVAC, industrial, and refrigeration industries worldwide. |
1,250 | |||
| 38 |
STANLEY Engineered Fasteningstanleyengineeredfastening.com
provides advanced fastening and assembly products with global support, engineering expertise, and rapid onsite customer service worldwide |
1,181 | |||
| 39 |
Cystic Fibrosis Foundationcff.org
Nonprofit dedicated to finding a cure and improving lives for those with cystic fibrosis through research, care, and advocacy for better health experiences and outcomes. |
1,152 | |||
| 40 | 1,147 | ||||
| 41 |
U.S. Army DEVCOM Army Research Laboratoryarl.devcom.army.mil
Official page Content shared does not imply endorsement Stay updated on company news and announcements here |
1,134 | |||
| 42 |
MESO SCALE DIAGNOSTICS, LLC.mesoscale.com
Develops, manufactures, and commercializes assays and instruments for measuring molecules in biological samples, supporting medical research and drug development with proprietary technology. |
1,035 | |||
| 43 |
Johns Hopkins Whiting School of Engineeringengineering.jhu.edu
The company's faculty and students work on cutting-edge research in various fields including wind engineering, computational medicine, and surgical robotics |
992 | |||
| 44 |
Novavaxnovavax.com
Creating accessible next generation vaccines to combat infectious diseases and viral threats, driven by passion for global health and guided by science and technology |
972 | |||
| 45 | 931 | ||||
| 46 |
MedImmuneparkedpage.astrazeneca.com
Global biologics research and development arm focused on discovering, developing, and commercializing small molecule and biologic prescription medicines across various medical areas |
888 | |||
| 47 |
EA Engineering, Science, and Technology, Inc., PBCeaest.com
An employee-owned public benefit corporation providing environmental, compliance, natural resources, and infrastructure engineering and management solutions to public and private clients nationwide |
880 | |||
| 48 |
Tasly Pharmaceutica Group Co., Ltd.tasly.com
Overseas headquarters of a China-based pharmaceutical company, publicly traded on the Shanghai exchange, focusing on healthcare products and services |
875 | |||
| 49 |
Supernus Pharmaceuticals, Inc.supernus.com
A pharmaceutical company specializing in developing and marketing products for central nervous system diseases, including treatments for ADHD, epilepsy, migraine, and Parkinson's disease |
844 | |||
| 50 |
Tatetateglobal.com
The company specializes in access floor and underfloor service distribution solutions for high-performance, sustainable commercial and data center environments, optimizing energy efficiency and infrastructure flexibility |
817 | |||
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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 11, 2026.
More company lists in Maryland
- The largest companies in Maryland 1,688
- Multinational companies in Maryland 216
- IT Services and IT Consulting companies in Maryland 189
- IT services companies in Maryland 179
- Professional services firms in Maryland 176
- Education providers in Maryland 151
- Hospitals and Health Care companies in Maryland 114
- Consulting firms in Maryland 112
- Healthcare providers in Maryland 105
- Critical infrastructure operators in Maryland 94
- Retail chains in Maryland 91
- Public sector organisations in Maryland 91
- Financial services firms in Maryland 88
- Aerospace and defence companies in Maryland 80
- Construction companies in Maryland 80
- Manufacturers in Maryland 75
- Financial Services companies in Maryland 65
- Government Administration companies in Maryland 61
- Higher Education companies in Maryland 54
- Hardware manufacturers in Maryland 53
- Research institutes in Maryland 52
- SaaS companies in Maryland 52
- Companies with a mobile app in Maryland 49
- AI companies in Maryland 48
The same list elsewhere in United States
- Companies with in-house R&D in the United States 6,796
- Companies with in-house R&D in California 1,276
- Companies with in-house R&D in Texas 442
- Companies with in-house R&D in New York State 419
- Companies with in-house R&D in Massachusetts 396
- Companies with in-house R&D in Illinois 322
- Companies with in-house R&D in Michigan 287
- Companies with in-house R&D in Ohio 277
- Companies with in-house R&D in Pennsylvania 255
- Companies with in-house R&D in New Jersey 224
- Companies with in-house R&D in Florida 221
- Companies with in-house R&D in Alabama 214
- Companies with in-house R&D in Georgia 173
- Companies with in-house R&D in Virginia 166
- Companies with in-house R&D in North Carolina 158
- Companies with in-house R&D in Wisconsin 154
- Companies with in-house R&D in Minnesota 146
- Companies with in-house R&D in Washington State 140
- Companies with in-house R&D in Colorado 113
- Companies with in-house R&D in Indiana 104
- Companies with in-house R&D in New York 223
- Companies with in-house R&D in San Francisco 147
- Companies with in-house R&D in Houston 129
- Companies with in-house R&D in San Jose 103