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Top Cybersecurity companies in San Francisco

Companies defending or attacking software, networks, and cloud infrastructure. Filtered to companies headquartered in San Francisco.

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Built from a search like: “Top Cybersecurity companies in San Francisco”

Ranked by current headcount across Cybersecurity companies headquartered in San Francisco. Refreshed daily.

  1. 1
    Cloudflare· San Francisco, California, United States
    • Post-IPO debt
    • 7.5k employees
    • Founded 2009
  2. 2
    HackerOne· San Francisco, California, United States
    • Series unknown
    • 6.9k employees
    • Founded 2012
  3. 3
    Bugcrowd· San Francisco, California, United States
    • Debt
    • 3.7k employees
    • Founded 2012
  4. 4
    Armis· San Francisco, California, United States
    • Series unknown
    • 1.1k employees
    • Founded 2015
  5. 5
    Sysdig· San Francisco, California, United States
    • Series G
    • 626 employees
    • Founded 2013
Reveal 117 more·100 free credits, no card

Find engineers at Cybersecurity companies in San Francisco

San Francisco has long been a hub for Cybersecurity, and the list above ranks the largest Cybersecurity companies headquartered there by current headcount, drawn from public LinkedIn and Crunchbase records. With 122 matching companies in our index, this is a good map of where the Cybersecurity talent in San Franciscolives - useful whether you’re recruiting, partnering, or sizing a market.

The biggest Cybersecurity companies in San Francisco tend to be the gravitational centres for specialised talent - senior engineers, ML researchers, applied scientists, designers - while the smaller ones compete on speed, equity, and proximity to founders.

Refolk converts this list into a live search. Ask for “Cybersecurity engineers in San Franciscohiring senior staff” or “founders of Cybersecurity companies in San Franciscowho left in the last 12 months” and Refolk returns a ranked shortlist with the evidence that earned each person a spot.

How this list is built

Refolk pulled Cybersecurity companies headquartered in San Francisco from public LinkedIn and Crunchbase records, ranked them by current employee count, and kept those with at least 10 employees. The list refreshes once a day.

Last refreshed: Sun, 21 Jun 2026 10:37:22 GMT

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