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Top Series A Cybersecurity companies

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

Built from a search like: Top Series A Cybersecurity companies

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

  1. 1
    Radware· Tel Aviv-Yafo, Tel Aviv District, Israel
    • Series A
    • 1.6k employees
    • Founded 1997
  2. 2
    Trustwave, A LevelBlue Company· Chicago, Illinois, United States
    • Series A
    • 785 employees
    • Founded 1995
  3. 3
    SEQURETEK· Little Rock, Arkansas, United States
    • Series A
    • 371 employees
    • Founded 2013
  4. 4
    Yogosha· Paris, Île-de-France, France
    • Series A
    • 205 employees
    • Founded 2015
  5. 5
    CYE· Herzliya, Tel Aviv District, Israel
    • Series A
    • 182 employees
    • Founded 2012
  6. 6
    PROFICIO· Irvine, California, United States
    • Series A
    • 181 employees
    • Founded 2010
  7. 7
    Koi· Tel Aviv-Yafo, Tel Aviv District, Israel
    • Series A
    • 178 employees
    • Founded 2023
  8. 8
    HiddenLayer· Austin, Texas, United States
    • Series A
    • 168 employees
    • Founded 2022
  9. 9
    QNu Labs· Bengaluru, Karnataka, India
    • Series A
    • 155 employees
    • Founded 2016
  10. 10
    Dropsuite· Melbourne, Victoria, Australia
    • Series A
    • 154 employees
    • Founded 2012
  11. 11
    Guardz· Miami, Florida, United States
    • Series A
    • 152 employees
    • Founded 2022
  12. 12
    • Series A
    • 152 employees
    • Founded 1995
  13. 13
    TypingDNA· Brooklyn, New York, United States
    • Series A
    • 150 employees
    • Founded 2016
  14. 14
    Praetorian· Austin, Texas, United States
    • Series A
    • 142 employees
    • Founded 2010
  15. 15
    • Series A
    • 139 employees
    • Founded 2020
  16. 16
    HarfangLab· Paris, Île-de-France, France
    • Series A
    • 129 employees
    • Founded 2018
  17. 17
    Mimic· Palo Alto, California, United States
    • Series A
    • 129 employees
    • Founded 2023
  18. 18
    Satori· Eatontown, New Jersey, United States
    • Series A
    • 128 employees
    • Founded 2019
  19. 19
    ITrust· Labège, Occitanie, France
    • Series A
    • 127 employees
    • Founded 2007
  20. 20
    Seal Security· New York, New York, United States
    • Series A
    • 114 employees
    • Founded 2022
  21. 21
    IONIX· Tel Aviv-Yafo, Tel Aviv District, Israel
    • Series A
    • 108 employees
    • Founded 2017
  22. 22
    • Series A
    • 104 employees
    • Founded 2023
  23. 23
    LayerX Security· New York, New York, United States
    • Series A
    • 101 employees
    • Founded 2021
  24. 24
    Data Resolve Technologies· Noida, Uttar Pradesh, India
    • Series A
    • 97 employees
    • Founded 2013
  25. 25
    Batuta· San Francisco, California, United States
    • Series A
    • 97 employees
    • Founded 2019

Find engineers and founders at Series A Cybersecurity companies

Series A 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 A, by current headcount, drawn from public LinkedIn and Crunchbase records. Across 270matching 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 A Cybersecurity founders hiring senior engineers” or “design leads at Series A 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 A 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 05:57:01 GMT

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