| # | Company | Employees |
|---|---|---|
| 1 |
General Dynamics UKgd.com
A global company focusing on safety and security, producing a range of products from business jets to submarines with a culture of continuous improvement |
100,000 |
| 2 |
Leidosleidos.com
Global technology leader providing digital mission innovations and efficient technical services for government and commercial customers through a diverse, flexible work environment. |
37,171 |
| 3 | 36,645 | |
| 4 |
CACI International Inccaci.com
providing advanced technology and expert services to address complex national security challenges for government and defense sectors |
22,223 |
| 5 |
Peratonperaton.com
A company at the forefront of solving global challenges with innovative solutions, prioritizing safety and security through fresh perspectives and talent |
18,000 |
| 6 |
ASRC Federalasrcfederal.com
Providing technology and expertise to federal defense and civilian agencies, supporting missions from space exploration to cybersecurity and infrastructure. |
5,051 |
| 7 | 3,124 | |
| 8 |
Engility Corporationsaic.com
A premier technology integrator based in Reston, Virginia, providing information about SAIC through their linkedin page |
1,414 |
| 9 |
Noblisnoblis.org
A nonprofit organization providing scientific, technology, and strategy services to government and industry clients in national security, healthcare, and environmental sustainability |
1,313 |
| 10 |
Tyto Athene, LLCgotyto.com
Specializing in mission-focused digital transformation, our experts offer expertise in Network Modernization, Hybrid Cloud, Cyber Security, and Enterprise IT for defense and security sectors |
967 |
| 11 |
NCI Information Systems, Inclinkedin.com
The company, now known as Empower AI, specializes in artificial intelligence technology Follow their LinkedIn page for updates |
936 |
| 12 |
Synergysynergybis.com
Federal IT firm specializing in cloud, low/no code SaaS platforms, delivering agile MVP solutions to accelerate agency modernization goals. |
865 |
| 13 |
AIS (Applied Information Sciences)ais.com
IT transformation firm specializing in compliant cloud and data solutions for large enterprises, governments, and defense agencies, driving innovation and modernization |
768 |
| 14 |
L-3 National Security Solutionscaci.com
A company that was acquired by CACI International Inc on February 1, 2016, specializing in national security solutions Visit https://wwwlinkedincom/company/caci-international-inc |
729 |
| 15 |
Sallyport Globalacuityinternational.com
Global provider of security and mission support solutions tailored for security and stability operations worldwide, focused on exceeding customer requirements with core values of integrity and quality |
704 |
| 16 |
MetroStarmetrostar.com
Leading provider of secure digital transformation and AI-enabled products and solutions, specializing in delivering cutting-edge IT services to government agencies and defense organizations. |
620 |
| 17 |
Aleut Federalaleutfederal.com
A federal services company under The Aleut Corporation offering technology, environmental, construction, and infrastructure services through SBA-certified subsidiaries |
504 |
| 18 |
Empower AIempower.ai
Empower AI specializes in boosting workforce productivity for federal agencies through tailored solutions, enabling faster decision-making and mission advancement |
468 |
| 19 |
HydroGeoLogic, Inc.hgl.com
Employee-owned company with 36 years of experience providing innovative engineering and remediation solutions to reverse environmental impacts, restore natural resources, and support clients |
458 |
| 20 |
KIHOMACkihomac.com
An aerospace and defense acquisition and technology company, offering system acquisition and life cycle management support to government agencies |
388 |
| 21 |
Titan Corporationl3harris.com
Former defense contractor turned technology company, specializing in wireless communications, information systems, and electron beam technology for food safety Acquired by L-3 Communications in 2005 |
355 |
| 22 |
ISIisidefense.com
A leader in security for government contractors, offering tailored solutions, compliance support, expertise in CMMC, clearances, software, and security empowerment |
340 |
| 23 |
Evolverevolverinc.com
A technology company offering IT transformation and cybersecurity services to government and commercial clients, focusing on security, innovation, and operational efficiency |
325 |
| 24 |
Whitney, Bradley & Brown (WBB)wbbinc.com
A government and public sector solutions provider focused on innovative advances in technology and methodologies to meet client challenges effectively |
324 |
| 25 | 308 | |
| 26 |
Xator Corporationparsons.com
Provider of mission-focused C4ISR solutions for US Government clients, specializing in intelligence, critical infrastructure protection, training, and strategic management |
267 |
| 27 |
SES Space & Defensesessd.com
Equipping governments with integrated satellite and connectivity solutions, delivering resilient, future-proof capabilities across every mission, landscape, and orbit. |
250 |
| 28 |
Metron Inc.metsci.com
Provider of research, scientific, and software solutions for government and commercial markets Specializing in data analytics, autonomous solutions, and remote sensing systems |
242 |
| 29 |
Data Machinesdatamachines.com
A data analytics company specializing in cloud architectures, solving complex problems in data analytics, DevSecOps, machine intelligence, and data science |
45 |
| 30 |
Johnson Technology Systems, Inc. (JTSi)jtsusa.com
An IT and Engineering Services provider specializing in delivering mission-critical professional IT services, with a focus on SAP/ERP solutions for the Public Sector |
34 |
| 31 |
MP Data LLC (USA)mpdata-llc.com
Small Business specializing in application development, data, cloud computing, and professional services for government agencies 15 years of experience delivering cost-effective IT solutions |
17 |
| 32 |
Systems Development and Analysissystemsdev.com
This company focuses on clients' missions, providing independent and innovative technology solutions at the interfaces of IT, business, and operations |
10 |
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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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