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Top Series B Cybersecurity companies

Companies defending or attacking software, networks, and cloud infrastructure. Filtered to companies whose latest disclosed round is Series B.

Built from a search like: “Top Series B Cybersecurity companies”

Ranked by current headcount across Series B Cybersecurity companies. Refreshed daily.

  1. 1
    Fortinet· Sunnyvale, California, United States
    • Series B
    • 16k employees
    • Founded 2014
  2. 2
    Hack The Box· Folkestone, England, United Kingdom
    • Series B
    • 2.3k employees
    • Founded 2017
  3. 3
    [redacted]· Austin, Texas, United States
    • Series B
    • 1k employees
    • Founded 2015
  4. 4
    Intigriti· Antwerp, Flemish Region, Belgium
    • Series B
    • 686 employees
    • Founded 2016
  5. 5
    Quantinuum· Broomfield, Colorado, United States
    • Series B
    • 624 employees
    • Founded 2021
  6. 6
    Aujas Cybersecurity· Cupertino, California, United States
    • Series B
    • 618 employees
    • Founded 2008
  7. 7
    AppViewX· New York, New York, United States
    • Series B
    • 557 employees
    • Founded 2008
  8. 8
    Cobalt· San Francisco, California, United States
    • Series B
    • 534 employees
    • Founded 2013
  9. 9
    QAX Technology Group· Hong Kong SAR
    • Series B
    • 499 employees
    • Founded 2014
  10. 10
    XM Cyber· Tel Aviv-Yafo, Tel Aviv District, Israel
    • Series B
    • 451 employees
    • Founded 2016
  11. 11
    Upwind Security· San Francisco, California, United States
    • Series B
    • 391 employees
    • Founded 2022
  12. 12
    Bishop Fox· Tempe, Arizona, United States
    • Series B
    • 377 employees
    • Founded 2005
  13. 13
    iboss· Boston, Massachusetts, United States
    • Series B
    • 360 employees
    • Founded 2003
  14. 14
    ReversingLabs· Cambridge, Massachusetts, United States
    • Series B
    • 330 employees
    • Founded 2009
  15. 15
    Panther· San Francisco, California, United States
    • Series B
    • 293 employees
    • Founded 2018
  16. 16
    SpecterOps· Alexandria, Virginia, United States
    • Series B
    • 282 employees
    • Founded 2017
  17. 17
    Sublime Security· Washington, District of Columbia, United States
    • Series B
    • 280 employees
    • Founded 2019
  18. 18
    TXOne Networks· Taipei, Taipei City, Taiwan
    • Series B
    • 279 employees
    • Founded 2019
  19. 19
    SOCRadar® Extended Threat Intelligence· Newark, Delaware, United States
    • Series B
    • 271 employees
    • Founded 2019
  20. 20
    Hoxhunt· Helsinki, Uusimaa, Finland
    • Series B
    • 265 employees
    • Founded 2016
  21. 21
    EfficientIP· La Garenne-Colombes, Île-de-France, France
    • Series B
    • 262 employees
    • Founded 2004
  22. 22
    Eye Security· The Hague, South Holland, Netherlands
    • Series B
    • 257 employees
    • Founded 2020
  23. 23
    Cyble· Cupertino, California, United States
    • Series B
    • 242 employees
    • Founded 2019
  24. 24
    CloudSEK· Singapore, Singapore
    • Series B
    • 237 employees
    • Founded 2015
  25. 25
    Riot· San Francisco, California, United States
    • Series B
    • 220 employees
    • Founded 2020

Find engineers and founders at Series B Cybersecurity companies

Series B Cybersecurity companies are some of the most active hirers in the market. The list above ranks the largest Cybersecurity companies whose latest disclosed round is Series B, by current headcount, drawn from public LinkedIn and Crunchbase records. Across 164matching companies, you’ll find senior engineers, founding designers, and operators worth tracking.

Companies at this stage in Cybersecurity share a profile: a working product, fresh capital, and a hiring plan that wants senior people yesterday. Looking at headcount, last round, and HQ side by side gives you a quick read on where Cybersecurity talent is concentrating right now.

Refolk converts this list into a search. Ask for “Series B Cybersecurity founders hiring senior engineers” or “design leads at Series B Cybersecurity companies” and Refolk returns a fresh ranked shortlist with the sources behind each match.

How this list is built

Refolk pulled Cybersecurity companies whose latest disclosed funding round is Series B from public LinkedIn and Crunchbase records, ranked them by current employee count, and kept those with at least 5 employees. The list refreshes once a day.

Last refreshed: Thu, 07 May 2026 06:56:21 GMT

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