Company lists · Data refreshed September 2026

Top 25 Appsec companies based in the United States

RevenueBase identified 3,230 appsec companies headquartered in the United States as of September 2026 and tracks 93,834 professional contacts across them, including 41,488 with verified work emails. San Francisco is the largest hub.

This list covers appsec companies headquartered in the United States, matched on what each company actually does as described in its own words. Ranked by team size, largest first. Every row shows the company's own description, its RevenueBase Smart Search rating, and when it was last checked. Data refreshed September 21, 2026.

Published by RevenueBase, a B2B data infrastructure company. This list was built with RevenueBase Smart Search, the natural-language company search RevenueBase customers use to build their own targeted lists and unlock verified emails and direct dials at the companies on them. How these lists are built and judged.

How to read this list HQ checked on every row RevenueBase Smart Search rating on every row Refreshed Sep 21, 2026 86% judged on-target in blind review
3,230Companies
93,834Contacts tracked
41,488Verified emails
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The 25 largest appsec companies based in the United States

Ranked by team size
Top 25 of 3,230 appsec companies based in the United States, ranked by team size, largest first. Data refreshed Sep 21, 2026. RevenueBase Smart Search rates how each company's information relates to appsec companies: strong evidence (its own description names it), partial (names part of it), indirect (matched on the rest of its profile rather than the description shown). Click a contact count to view that company's people.
#CompanyRevenueBase Smart SearchHeadquartersEmployeesContacts
1Indirect evidenceSunnyvale, CA, United StatesHQ checked Sep 21, 202610001+14,289 contacts →

Indirect evidence

“Fortinet makes possible a digital world that we can always trust through its mission to protect people, devices, and data everywhere.”

Source: RevenueBase Database · checked Sep 21, 2026
2Indirect evidenceSan Francisco, CA, United StatesHQ checked Sep 21, 2026n/a6,058 contacts →

Indirect evidence

“HackerOne is a global leader in Continuous Threat Exposure Management (CTEM) and the only solution provider that pairs the simultaneous trust of the Fortune 500 and the world's…”

Source: RevenueBase Database · checked Sep 21, 2026
3Indirect evidenceSan Francisco, CA, United StatesHQ checked Sep 21, 2026n/a3,649 contacts →

Indirect evidence

“We are a crowdsourced security company that safeguards organizations' assets from sophisticated threat actors before they can strike-by uniting our customers with trusted hackers…”

Source: RevenueBase Database · checked Sep 21, 2026
4Indirect evidenceNewton, MA, United StatesHQ checked Sep 21, 20261,001-5,0003,302 contacts →

Indirect evidence

“CyberArk is the global leader in Identity Security.”

Source: RevenueBase Database · checked Sep 21, 2026
5Indirect evidenceFoster City, CA, United StatesHQ checked Sep 21, 20261,001-5,0003,058 contacts →

Indirect evidence

“Qualys, Inc.(NASDAQ: QLYS) is a leading provider of disruptive cloud-based security, compliance and IT solutions with more than subscription customers worldwide, including a…”

Source: RevenueBase Database · checked Sep 21, 2026
6Indirect evidenceJohns Creek, GA, United StatesHQ checked Sep 21, 20261,001-5,0001,669 contacts →

Indirect evidence

“BeyondTrust is the global cybersecurity leader protecting Paths to Privilege™.”

Source: RevenueBase Database · checked Sep 21, 2026
7Indirect evidenceAustin, TX, United StatesHQ checked Sep 21, 20261,001-5,0001,252 contacts →

Indirect evidence

“Thales is a global leader in cybersecurity, helping the most trusted organizations in the world protect their most critical applications, data, and identities anywhere at scale.”

Source: RevenueBase Database · checked Sep 21, 2026
8Indirect evidenceReston, VA, United StatesHQ checked Sep 21, 20261,001-5,0001,232 contacts →

Indirect evidence

“GuidePoint Security provides trusted cybersecurity expertise, solutions, and services that help organizations make informed decisions and minimize risk.”

Source: RevenueBase Database · checked Sep 21, 2026
9Indirect evidenceAustin, TX, United StatesHQ checked Sep 21, 202610001+1,217 contacts →

Indirect evidence

“On Dec.”

Source: RevenueBase Database · checked Sep 21, 2026
10Indirect evidenceBoston, MA, United StatesHQ checked Sep 21, 20261,001-5,0001,188 contacts →

Indirect evidence

“Snyk, the leader in secure AI software development, empowers organizations to build fast and stay secure by unleashing developer productivity and reducing business risk.”

Source: RevenueBase Database · checked Sep 21, 2026
11Indirect evidenceBurlington, MA, United StatesHQ checked Sep 21, 20265,001-10,0001,187 contacts →

Indirect evidence

“Black Duck® meets the board-level risks of modern software with True Scale Application Security, ensuring uncompromised trust in software for the regulated, AI-powered world.”

Source: RevenueBase Database · checked Sep 21, 2026
12Indirect evidenceSeattle, WA, United StatesHQ checked Sep 21, 20261,001-5,0001,059 contacts →

Indirect evidence

“WatchGuard® Technologies, Inc.”

Source: RevenueBase Database · checked Sep 21, 2026
13Indirect evidenceParamus, NJ, United StatesHQ checked Sep 21, 2026501-1,0001,042 contacts →

Indirect evidence

“Checkmarx helps the world’s largest enterprises get ahead of application risk without slowing down development.”

Source: RevenueBase Database · checked Sep 21, 2026
14Indirect evidenceBaltimore, MD, United StatesHQ checked Sep 21, 2026501-1,000904 contacts →

Indirect evidence

“ZeroFox is the solution to discover, validate, and disrupt external cyber threats before they harm revenue or reputation.”

Source: RevenueBase Database · checked Sep 21, 2026
15Indirect evidenceChicago, IL, United StatesHQ checked Sep 21, 2026501-1,000874 contacts →

Indirect evidence

“Trustwave, a LevelBlue Company, is a globally recognized cybersecurity leader that reduces cyber risk and fortifies organizations against disruptive and damaging cyber threats.”

Source: RevenueBase Database · checked Sep 21, 2026
16Indirect evidenceKansas City, MO, United StatesHQ checked Sep 21, 20261,001-5,000844 contacts →

Indirect evidence

“Today’s threatscape is relentless.”

Source: RevenueBase Database · checked Sep 21, 2026
17Indirect evidenceAustin, TX, United StatesHQ checked Sep 21, 2026n/a813 contacts →

Indirect evidence

“The Synack Red Team is a private freelance security research team that spans 6 continents and over 80 countries.”

Source: RevenueBase Database · checked Sep 21, 2026
18Indirect evidencePlano, TX, United StatesHQ checked Sep 21, 2026501-1,000641 contacts →

Indirect evidence

“At Network Intelligence, we combine our team of 500+ security professionals with Transilience – our cutting-edge AI platform.”

Source: RevenueBase Database · checked Sep 21, 2026
19Indirect evidenceAshburn, VA, United StatesHQ checked Sep 21, 2026501-1,000629 contacts →

Indirect evidence

“Telos Corporation (NASDAQ: TLS) empowers and protects the world’s most security-conscious organizations with efficient, adaptable, and secure solutions that safeguard people…”

Source: RevenueBase Database · checked Sep 21, 2026
20Indirect evidenceChicago, IL, United StatesHQ checked Sep 21, 20261,001-5,000628 contacts →

Indirect evidence

“VikingCloud delivers battle-tested cybersecurity and compliance solutions that simply work.”

Source: RevenueBase Database · checked Sep 21, 2026
21Indirect evidenceMinneapolis, MN, United StatesHQ checked Sep 21, 2026501-1,000587 contacts →

Indirect evidence

“NetSPI® pioneered Penetration Testing as a Service (PTaaS) and leads the industry in modern, continuous pentesting.”

Source: RevenueBase Database · checked Sep 21, 2026
22Indirect evidenceBloomfield, NJ, United StatesHQ checked Sep 21, 202651-200566 contacts →

Indirect evidence

“Comodo - Protecting Your Digital World At Comodo, we are dedicated to safeguarding your digital property with Comodo Website Security.”

Source: RevenueBase Database · checked Sep 21, 2026
23Indirect evidenceBurlington, MA, United StatesHQ checked Sep 21, 2026501-1,000552 contacts →

Indirect evidence

“Veracode is a global leader in Application Risk Management for the AI era.”

Source: RevenueBase Database · checked Sep 21, 2026
24Indirect evidenceNew York, NY, United StatesHQ checked Sep 21, 2026501-1,000535 contacts →

Indirect evidence

“Funded by world-class investors, including Evolution Equity Partners, Silver Lake Partners, Sequoia Capital, GV, Riverwood Capital, and others, SecurityScorecard is the global…”

Source: RevenueBase Database · checked Sep 21, 2026
25Indirect evidenceMclean, VA, United StatesHQ checked Sep 21, 2026501-1,000523 contacts →

Indirect evidence

“UltraViolet Cyber is the only security operations partner that unifies red, blue, and purple team capabilities into one integrated program, finding what's vulnerable, stopping…”

Source: RevenueBase Database · checked Sep 21, 2026

Showing 25 of 3,230 appsec companies based in the United States

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Appsec companies based in the United States at a glance

As of Sep 21, 2026
44.2%Verified-email coverage
29.1Average contacts per company
1-10Median size (employees)
4.5%Largest-city concentration · San Francisco
Sep 21, 2026Page data refreshed

Companies by employee count

1-10
1,767
11-50
1,035
51-200
293
201-500
71
501-1,000
23
1,001-5,000
28
5,001-10,000
2
10001+
7

Email recency for this list is measured worldwide rather than for United States, so it is reported there. Company counts and contact totals on this page are exact for United States, over 3,230 companies.

How this list was built

Company categories are rarely black and white. RevenueBase reads each company's own description of its business to decide whether it belongs among appsec companies, so some rows will be adjacent to the category rather than pure plays. The description and RevenueBase Smart Search rating on every row are there so you can check each match yourself.

Source
The RevenueBase company graph: 60 million companies and 398.9 million professional contacts resolved from primary sources, queried with RevenueBase Smart Search, the natural-language company search available to every RevenueBase user.
What qualifies
Companies headquartered in the United States whose own description of what they do matches “appsec companies”. Matching reads each company's description, not its industry code or its name.
RevenueBase Smart Search
RevenueBase Smart Search is how this list is assembled and how each row is rated. RevenueBase's data engine and AI assess a company's LinkedIn profile, information supplied directly by the company, its website and other publicly available information, then relate it to a category defined in a user's own words. Each row is rated strong evidence (its own description names appsec companies), partial evidence (it names part of the category) or indirect evidence (the description shown names none of it and the match rests on the rest of the company's profile). The description supporting each rating is quoted on the row.
What we exclude
Companies whose own description does not clearly place them among appsec companies, and records with no verified work email. Companies headquartered outside United States are excluded even when they keep an office there.
Match quality
In blind human judging of this matching method, 86% of matched companies were on target. Expect roughly 1 in 7 rows to be adjacent to the category rather than a pure play. Every row shows the company's own description and its RevenueBase Smart Search rating so you can judge each match yourself. Read the full methodology: how the lists are built, how the judging worked, and what the figure means.
Ranking
Team size, largest first: companies are ordered by the number of professionals RevenueBase tracks at each one. Employee ranges shown are reported bands, for context.
Verification
Every listed company carries at least one verified work email, 41,488 across the full list. Contacts re-verify on a rolling cadence, and each contact's own verification date is shown inside RevenueBase.
Refresh
This page's figures were pulled from the company graph on September 21, 2026. Lists refresh periodically as the graph is re-checked.
Corrections
Wrong category, wrong headquarters, or a company that has closed? Use “Report an issue” on any row. Reports go to the RevenueBase Data Team and feed back into the company graph.

Frequently asked

What is RevenueBase Smart Search?

RevenueBase Smart Search is how RevenueBase decides which companies belong on this list and how strongly each one fits. Its data engine and AI assess a company's LinkedIn profile, information supplied directly by the company, its website and other publicly available information, then relate it to the category the list is about. Each row is rated strong evidence when the company's own description names appsec companies, partial evidence when it names part of the category, and indirect evidence when the description shown names none of it and the match rests on the rest of the company's profile.

How many appsec companies are there based in the United States?

RevenueBase identified 3,230 appsec companies headquartered in the United States as of September 2026, matched on each company's own description of what it does rather than its industry code.

What is the largest company on this list?

Fortinet, headquartered in Sunnyvale, tops this list with the largest team on record.

Which city has the most appsec companies?

San Francisco leads with 145 headquartered companies, followed by New York (123) and Austin (93).

How do I get contact information for these companies?

A free RevenueBase account lets you run this exact search and work the top results, verified emails and direct dials included. Upgrading unlocks all 41,488 verified decision-maker contacts tracked across these 3,230 companies.

How current is this list?

The list refreshes periodically as the company graph is re-checked. This page's figures were pulled on September 21, 2026.

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About this data

RevenueBase is a B2B data infrastructure company. Its company graph covers 60 million companies and 398.9 million professional contacts, with emails verified on a rolling cadence rather than scraped once and left to decay. These company lists are generated directly from that graph with RevenueBase Smart Search, the same natural-language company search every RevenueBase user has: describe a market in plain words, get the companies that match, and add verified emails and direct dials for the people at them. It is the same data that powers RevenueBase's B2B data products, and a free account includes 500 credits to start. How these lists are built and judged.