Company lists · Data refreshed September 2026

Top 25 Ot cybersecurity companies based in the United States

Name: Ot cybersecurity companies based in the United States
Creator: RevenueBase
License: https://creativecommons.org/licenses/by/4.0/

Compiled by the RevenueBase Data Team Data refreshed Sep 21, 2026 2,628 companies tracked

RevenueBase identified 2,628 ot cybersecurity companies headquartered in the United States as of September 2026 and tracks 135,144 professional contacts across them, including 64,223 with verified work emails. New York is the largest hub.

This list covers ot cybersecurity 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

2,628Companies

135,144Contacts tracked

64,223Verified emails

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The 25 largest ot cybersecurity companies based in the United States

Ranked by team size

Top 25 of 2,628 ot cybersecurity 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 ot cybersecurity 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.
#	Company	RevenueBase Smart Search	Headquarters	Employees	Contacts
1	Palo Alto Networks	Partial evidence	Santa Clara, CA, United StatesHQ checked Sep 21, 2026	10001+	18,431 contacts →
	Partial evidence “Palo Alto Networks, the global cybersecurity leader, is shaping the cloud-centric future with technology that is transforming the way people and organizations operate.” Source: RevenueBase Database · checked Sep 21, 2026
2	Fortinet	Indirect evidence	Sunnyvale, CA, United StatesHQ checked Sep 21, 2026	10001+	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
3	Symantec	Partial evidence	San Jose, CA, United StatesHQ checked Sep 21, 2026	10001+	11,169 contacts →
	Partial evidence “Your backstage pass to the most epic cybersecurity solutions on the market for Endpoint, Network, Data and Cloud security.” Source: RevenueBase Database · checked Sep 21, 2026
4	Crowdstrike	Partial evidence	Remote, United StatesHQ checked Sep 21, 2026	5,001-10,000	10,118 contacts →
	Partial evidence “CrowdStrike (Nasdaq: CRWD), a global cybersecurity leader, has redefined modern security with the world’s most advanced cloud-native platform for protecting critical areas of…” Source: RevenueBase Database · checked Sep 21, 2026
5	Bugcrowd	Indirect evidence	San Francisco, CA, United StatesHQ checked Sep 21, 2026	n/a	3,649 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
6	Trellix	Partial evidence	Plano, TX, United StatesHQ checked Sep 21, 2026	1,001-5,000	3,447 contacts →
	Partial evidence “Trellix is a global cybersecurity company delivering intelligence-led cyber resilience for security-conscious organizations at any stage of their journey.” Source: RevenueBase Database · checked Sep 21, 2026
7	Sentinelone	Partial evidence	Mountain View, CA, United StatesHQ checked Sep 21, 2026	1,001-5,000	3,052 contacts →
	Partial evidence “SentinelOne is the world's leading AI-powered cybersecurity platform.” Source: RevenueBase Database · checked Sep 21, 2026
8	Sailpoint	Indirect evidence	Austin, TX, United StatesHQ checked Sep 21, 2026	1,001-5,000	2,886 contacts →
	Indirect evidence “SailPoint equips the modern enterprise to seamlessly manage and secure access to applications and data through the lens of identity – at speed and scale.” Source: RevenueBase Database · checked Sep 21, 2026
9	Rapid7	Partial evidence	Boston, MA, United StatesHQ checked Sep 21, 2026	1,001-5,000	2,822 contacts →
	Partial evidence “Rapid7, Inc.(NASDAQ: RPD) is a global leader in AI-powered managed cybersecurity operations, trusted to advance organizations’ cyber resilience.” Source: RevenueBase Database · checked Sep 21, 2026
10	OPTIV	Indirect evidence	Leawood, KS, United StatesHQ checked Sep 21, 2026	1,001-5,000	2,222 contacts →
	Indirect evidence “Optiv is the cyber advisory and solutions leader, delivering strategic and technical expertise to nearly companies across every major industry.” Source: RevenueBase Database · checked Sep 21, 2026
11	Barracuda	Partial evidence	Campbell, CA, United StatesHQ checked Sep 21, 2026	1,001-5,000	2,157 contacts →
	Partial evidence “Barracuda is a leading global cybersecurity company providing complete protection against complex threats for all size business.” Source: RevenueBase Database · checked Sep 21, 2026
12	Fortra	Partial evidence	Eden Prairie, MN, United StatesHQ checked Sep 21, 2026	1,001-5,000	1,648 contacts →
	Partial evidence “Fortra delivers AI-amplified cybersecurity solutions that help organizations use and protect data with confidence.” Source: RevenueBase Database · checked Sep 21, 2026
13	Reliaquest	Indirect evidence	Tampa, FL, United StatesHQ checked Sep 21, 2026	1,001-5,000	1,285 contacts →
	Indirect evidence “ReliaQuest exists to Make Security Possible.” Source: RevenueBase Database · checked Sep 21, 2026
14	Thales Cybersecurity Products	Partial evidence	Austin, TX, United StatesHQ checked Sep 21, 2026	1,001-5,000	1,252 contacts →
	Partial 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
15	Guidepoint Security	Partial evidence	Reston, VA, United StatesHQ checked Sep 21, 2026	1,001-5,000	1,232 contacts →
	Partial 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
16	PAS	Indirect evidence	Houston, TX, United StatesHQ checked Sep 21, 2026	201-500	1,231 contacts →
	Indirect evidence “PAS, part of Hexagon's Asset Lifecycle Intelligence division, delivers software solutions that prevent, detect, & remediate cyber threats, reduce process safety risks, and…” Source: RevenueBase Database · checked Sep 21, 2026
17	Imperva	Indirect evidence	Austin, TX, United StatesHQ checked Sep 21, 2026	10001+	1,217 contacts →
	Indirect evidence “On Dec.” Source: RevenueBase Database · checked Sep 21, 2026
18	Forescout Technologies INC	Indirect evidence	San Jose, CA, United StatesHQ checked Sep 21, 2026	1,001-5,000	1,181 contacts →
	Indirect evidence “As AI-driven vulnerability and exploitation accelerate attack velocity to machine speed, Forescout is a foundational cyber defense layer that allows organizations to segment and…” Source: RevenueBase Database · checked Sep 21, 2026
19	Opswat	Indirect evidence	Tampa, FL, United StatesHQ checked Sep 21, 2026	501-1,000	1,119 contacts →
	Indirect evidence “OPSWAT protects critical infrastructure.” Source: RevenueBase Database · checked Sep 21, 2026
20	Watchguard Technologies	Indirect evidence	Seattle, WA, United StatesHQ checked Sep 21, 2026	1,001-5,000	1,059 contacts →
	Indirect evidence “WatchGuard® Technologies, Inc.” Source: RevenueBase Database · checked Sep 21, 2026
21	Zerofox	Indirect evidence	Baltimore, MD, United StatesHQ checked Sep 21, 2026	501-1,000	904 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
22	Netenrich	Indirect evidence	San Jose, CA, United StatesHQ checked Sep 21, 2026	501-1,000	889 contacts →
	Indirect evidence “Netenrich is redefining security operations by shifting the focus from "efficiency"(speed) to "efficacy"(comprehensive coverage).” Source: RevenueBase Database · checked Sep 21, 2026
23	Trustwave, A Levelblue Company	Partial evidence	Chicago, IL, United StatesHQ checked Sep 21, 2026	501-1,000	874 contacts →
	Partial 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
24	Nortonlifelock	Indirect evidence	Tempe, AZ, United StatesHQ checked Sep 21, 2026	n/a	740 contacts →
	Indirect evidence “NortonLifeLock and Avast merged in 2022 and are now Gen™ (NASDAQ: GEN)- a global company dedicated to powering Digital Freedom through its trusted Cyber Safety brands.” Source: RevenueBase Database · checked Sep 21, 2026
25	Vectra AI	Partial evidence	San Jose, CA, United StatesHQ checked Sep 21, 2026	501-1,000	651 contacts →
	Partial evidence “Vectra AI is the cybersecurity AI leader in protecting modern networks from modern attacks.” Source: RevenueBase Database · checked Sep 21, 2026

RevenueBase Smart Search

RevenueBase Smart Search assesses information from a company’s LinkedIn profile, information supplied directly by the company, its website, and other publicly available sources. It uses that information to rate how closely the company relates to this list’s category: ot cybersecurity companies. Every row carries its rating and the description the rating was read from, so each one can be checked rather than taken on trust.

Strong evidence: The company's own public description of its business names ot cybersecurity companies.
Partial evidence: Its own public description names part of ot cybersecurity companies, so it works in or next to the category without describing itself that way.
Indirect evidence: The description shown does not name ot cybersecurity companies. The match rests on the rest of the company's public profile rather than the one sentence quoted here, so this is the rating to check first.

RevenueBase Smart Search is how these lists are built: RevenueBase's data engine and AI assemble the companies that match a category defined in a user's own words, so a list can be about what companies actually do rather than about whichever industry code they were filed under.

Showing 25 of 2,628 ot cybersecurity companies based in the United States

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Ot cybersecurity companies based in the United States at a glance

As of Sep 21, 2026

47.5%Verified-email coverage

51.4Average contacts per company

11-50Median size (employees)

3.4%Largest-city concentration · New York

Sep 21, 2026Page data refreshed

Companies by employee count

1-10

1,309

11-50

884

51-200

291

201-500

501-1,000

1,001-5,000

5,001-10,000

10001+

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 2,628 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 ot cybersecurity 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 “ot cybersecurity 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 ot cybersecurity 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 ot cybersecurity 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, 64,223 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.

Ot cybersecurity companies by metro

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 ot cybersecurity 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 ot cybersecurity companies are there based in the United States?

RevenueBase identified 2,628 ot cybersecurity 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?

Palo Alto Networks, headquartered in Santa Clara, tops this list with the largest team on record.

Which city has the most ot cybersecurity companies?

New York leads with 89 headquartered companies, followed by San Francisco (60) and Austin (57).

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 64,223 verified decision-maker contacts tracked across these 2,628 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.