Series A Cybersecurity companies in San Francisco
Companies defending or attacking software, networks, and cloud infrastructure. Filtered to Series A-stage companies headquartered in San Francisco.
Built from a search like: “Top Series A Cybersecurity companies in San Francisco”
Ranked by current headcount across Series A Cybersecurity companies in San Francisco. Refreshed daily.
- 1Batuta· San Francisco, California, United States
- Series A
- 97 employees
- Founded 2019
- 2Quantstamp, Inc.· San Francisco, California, United States
- Series A
- 68 employees
- Founded 2017
- 3Fable Security· San Francisco, California, United States
- Series A
- 55 employees
- Founded 2024
- 4Escape· San Francisco, California, United States
- Series A
- 54 employees
- Founded 2020
- 5Truffle Security Co.· San Francisco Bay Area
- Series A
- 53 employees
- Founded 2019
- 6Mondoo· San Francisco, California, United States
- Series A
- 51 employees
- Founded 2020
- 7ProjectDiscovery· San Francisco, California, United States
- Series A
- 50 employees
- Founded 2020
- 8SquareX· San Francisco Bay Area
- Series A
- 48 employees
- Founded 2023
- 9Monad· San Francisco, California, United States
- Series A
- 43 employees
- Founded 2020
- 10RAD Security· San Francisco, California, United States
- Series A
- 38 employees
- Founded 2021
- 11Cogent Security· San Francisco, California, United States
- Series A
- 35 employees
- Founded 2024
- 12Smallstep· San Francisco, California, United States
- Series A
- 30 employees
- Founded 2016
- 13SEWORKS· San Francisco, California, United States
- Series A
- 28 employees
- Founded 2015
- 14Upfort· San Francisco, California, United States
- Series A
- 27 employees
- Founded 2017
- 15Impart Security· San Francisco, California, United States
- Series A
- 24 employees
- Founded 2021
- 16Bridgecrew· San Francisco, California, United States
- Series A
- 6 employees
- Founded 2019
- 17Atomist· San Francisco, California, United States
- Series A
- 5 employees
- Founded 2015
- 18Codenomicon (acquired by Synopsys)· San Francisco, California, United States
- Series A
- 5 employees
- Founded 2001
- 19Altitude Networks· San Francisco, California, United States
- Series A
- 4 employees
- Founded 2018
- 20Solebit (Acquired by Mimecast)· San Francisco, California, United States
- Series A
- 3 employees
- Founded 2014
Find engineers at Series A Cybersecurity companies in San Francisco
Searching for “engineers at top Series A Cybersecurity companies in San Francisco” surfaces this slice of the market. The list above ranks Cybersecurity companies headquartered in San Francisco whose latest disclosed round is Series A, by current headcount, drawn from public LinkedIn and Crunchbase records. With 20 matching companies in our index, this is a tight read on where the Cybersecurity talent in San Francisco is heating up.
Three filters at once narrows the field hard. The companies that survive all three — Series A, Cybersecurity, in San Francisco — are usually the most targeted recruiting pool a hiring manager can ask for. Senior engineers, founding designers, and product leads here are about to become Cybersecurity’s next operators and angel investors.
Refolk converts this list into a live search. Ask for “senior engineers at Series A Cybersecurity companies in San Francisco hiring” or “founders of Series A Cybersecurity companies in San Francisco who left in the last year” and Refolk returns a ranked shortlist with the evidence behind each match.
How this list is built
Last refreshed: Thu, 07 May 2026 07:32:46 GMT
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