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Updated November 2026

37 Series B cybersecurity investors in the US

We list 37 Series B cybersecurity investors in the US as of November 2026: 35 have an SEC filing on file and 2 were checked on the firm's own website or an official register, and the list was last checked on 7 Nov 2026. The cities with the most head offices on this list are New York (6), Palo Alto (3) and San Francisco (2).

37investors
29with a fund filing or dated deal in the last 12 months
$200Mmedian fund size on file (SEC Form D, 28 firms)
239named decision-makers on file

Top 5 Series B cybersecurity investors in the US, ranked by recent fund activity

Among firms with a published profile and a dated fund or deal in the last 24 months. The rule: Activity score out of 100: recency of the latest fund filing or dated deal (30: full marks within 3 months, then stepping down at 6, 12 and 24 months), share of the observed portfolio in this sector (20; half of that when the sector is stated only), stage focus (15: all of it when Series B is the only stage the firm states, split evenly when it states more), stated focus on the US (15: full marks when the firm names the US as where it invests, half when it says global), size of the fund on file on a log scale (12) and completeness of the public record (8). Stage and regional focus are our research, not an SEC figure. It is a measure of activity and fit, not of quality or returns. The same rule orders the whole list; it is repeated in the method box.

  1. Alpha Partners

    Type: VC firm · HQ: New York, NY · Stages: Series B, Growth · Focus: Cybersecurity, AI, Developer Tools, Healthtech · Latest activity: New fund, Oct 2026 · Fund size on file: $200M (SEC Form D, 2024)

    Latest fund filing dated Oct 2026; $200M fund on file (SEC Form D, 2024); states cybersecurity as a focus; backs Series B, growth-stage; names the US as where it invests; 8 named decision-makers on file.

  2. Energy Impact Partners

    Type: VC firm · HQ: United States (London office) · Stages: Seed, Series A, Series B, Growth · Focus: Cybersecurity, Energy, Climate Tech, AI · Latest activity: Portfolio news, Nov 2026 · Fund size or assets: $4.5B (own site)

    Portfolio news dated Nov 2026; $4.5B on file (own site); states cybersecurity as a focus; backs seed, Series A, Series B; names the US as where it invests; 8 named decision-makers on file.

  3. Tribe Capital

    Type: VC firm · HQ: San Mateo, CA · Stages: Seed, Series A, Series B, Growth · Focus: Cybersecurity, AI, Crypto and Web3, Generalist · Latest activity: New fund, Oct 2026 · Fund size on file: $500M (SEC Form D, 2021)

    Latest fund filing dated Oct 2026; $500M fund on file (SEC Form D, 2021); states cybersecurity as a focus; backs seed, Series A, Series B; names the US as where it invests; 8 named decision-makers on file.

  4. Translink Capital

    Type: VC firm · HQ: Palo Alto, CA · Stages: Seed, Series A, Series B · Focus: Cybersecurity, AI, Developer Tools, Mobility · Latest activity: New fund, Sep 2026 · Fund size on file: $174M (SEC Form D, 2021)

    Latest fund filing dated Sep 2026; $174M fund on file (SEC Form D, 2021); states cybersecurity as a focus; backs seed, Series A, Series B; names the US as where it invests; 8 named decision-makers on file.

  5. Madrona

    Type: VC firm · HQ: Seattle, WA · Stages: Pre-seed, Seed, Series A, Series B, Growth · Focus: Cybersecurity, AI, Biotech, Consumer · Latest activity: New deal, Oct 2026 · Fund size on file: $490M (SEC Form D, 2025)

    Dated new deal in Oct 2026; $490M fund on file (SEC Form D, 2025); states cybersecurity as a focus; backs pre-seed, seed, Series A; names the US as where it invests; 8 named decision-makers on file.

First 18 of 37 Series B cybersecurity investors in the US

InvestorTypeHQStagesour researchFocusour researchLatest fund or dealFund sizeas filed or statedCheckedContacts
Alpha PartnersVC firmNew York, NYSeries B, GrowthCybersecurity, AI, Developer Tools, HealthtechNew fund, Oct 2026$200M (SEC Form D, 2024)4 Nov 20268 names, firm email · Unlock
Energy Impact PartnersVC firmUnited States (London office)Seed, Series A, Series B, GrowthCybersecurity, Energy, Climate Tech, AIPortfolio news, Nov 2026$4.5B (own site)5 Nov 20268 names · Unlock
Tribe CapitalVC firmSan Mateo, CASeed, Series A, Series B, GrowthCybersecurity, AI, Crypto and Web3, GeneralistNew fund, Oct 2026$500M (SEC Form D, 2021)4 Nov 20268 names, firm email · Unlock
Translink CapitalVC firmPalo Alto, CASeed, Series A, Series BCybersecurity, AI, Developer Tools, MobilityNew fund, Sep 2026$174M (SEC Form D, 2021)5 Nov 20268 names, firm email · Unlock
MadronaVC firmSeattle, WAPre-seed, Seed, Series A, Series B, GrowthCybersecurity, AI, Biotech, ConsumerNew deal, Oct 2026$490M (SEC Form D, 2025)5 Nov 20268 names · Unlock
EvolutionVC firmNew York, NYSeed, Series A, Series B, GrowthCybersecurity, AI, Developer Tools, SaaSNew fund, Sep 2026$1.2B (SEC Form D, 2026)4 Nov 20268 names · Unlock
AnsaVC firmNew York, NYSeries A, Series B, GrowthCybersecurity, AI, Healthtech, MediaNew fund, May 2026$200M (SEC Form D, 2026)4 Nov 20264 names, firm email · Unlock
FLF AccelerateVC firmTampa, FLPre-seed, Seed, Series A, Series BCybersecurity, AI, Fintech, MediaNew fund, Sep 2026$5M (SEC Form D, 2026)4 Nov 20268 names · Unlock
SignalFireVC firmSan Francisco, CASeed, Series A, Series B, GrowthCybersecurity, AI, Healthtech, Developer ToolsNew fund, May 2026$357M (SEC Form D, 2021)4 Nov 20268 names · Unlock
Massive VCVC firmBoulder, COSeed, Series A, Series BCybersecurity, Space, AI, EnergyNew fund, May 2026$30M (SEC Form D, 2026)4 Nov 20263 names · Unlock
SYN VenturesVC firmWest Palm Beach, FLSeed, Series A, Series BCybersecurity, AI, Defense Tech, Industrial TechNew fund, Oct 2026$300M (SEC Form D, 2022)4 Nov 20268 names · Unlock
Menlo VenturesVC firmMenlo Park, CAPre-seed, Seed, Series A, Series B, GrowthCybersecurity, AI, Media, RoboticsNew fund, Sep 2026$800M (SEC Form D, 2025)4 Nov 20268 names · Unlock
Westly Capital PartnersVC firmMenlo Park, CAPre-seed, Seed, Series A, Series B, GrowthCybersecurity, AI, Energy, Industrial TechNew fund, May 2026$500M (SEC Form D, 2026)4 Nov 20268 names · Unlock
Dallas Venture Capital I DVCVC firmIrving, TXSeed, Series A, Series BCybersecurity, AI, Fintech, DataNew deal, Oct 2026$75M (SEC Form D, 2021)5 Nov 20268 names, firm email · Unlock
Greenfield PartnersVC firmNew York, NYSeries A, Series B, GrowthCybersecurity, AI, Deep Tech, FintechNew fund, Jul 20264 Nov 20268 names · Unlock
VariantVC firmNew York, NYPre-seed, Seed, Series A, Series B, GrowthCybersecurity, Fintech, AI, Crypto and Web3New fund, Sep 2026$250M (SEC Form D, 2025)4 Nov 20268 names · Unlock
Atlas VenturesVC firmChicago, ILSeed, Series A, Series BCybersecurity, Logistics, AI, Industrial TechNew fund, Sep 2026$23M (SEC Form D, 2026)4 Nov 20263 names · Unlock
Ten Eleven VenturesVC firmUnited StatesSeed, Series A, Series B, GrowthCybersecurity, AI, SaaSNew deal, Sep 20265 Nov 20268 names · Unlock

You are seeing 18 of 37. The full list adds 19 more investors and 239 named decision-makers.

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How these 37 break down

By US state

US stateOn this listShare
California1027%
New York719%
Florida411%
Colorado25%

Method and limits

Source
35 of the 37 rows carry an SEC filing (Form D or Form ADV). All 37 have a website we checked. Filing date and fund size are SEC data where a filing exists. Stage, sector and check size are our research.
Inclusion rule
Organizations that back startups. Individuals, buyout funds and firms we found to be inactive are left out. Sector: the firm states cybersecurity as a focus on its own site, or we observed it in the firm's portfolio. Stage: the firm states that it invests at Series B.
Order
Firms with a published profile come first. Activity score out of 100: recency of the latest fund filing or dated deal (30: full marks within 3 months, then stepping down at 6, 12 and 24 months), share of the observed portfolio in this sector (20; half of that when the sector is stated only), stage focus (15: all of it when Series B is the only stage the firm states, split evenly when it states more), stated focus on the US (15: full marks when the firm names the US as where it invests, half when it says global), size of the fund on file on a log scale (12) and completeness of the public record (8). Stage and regional focus are our research, not an SEC figure. It is a measure of activity and fit, not of quality or returns.
Last refreshed
November 2026. Rows on this list were checked between 4 Nov 2026 and 7 Nov 2026.
Fill rates
Of 37 rows: stage 37, sector 37, fund size 32, website 37. In the paid file: named decision-makers on 35 rows, firm email on 11, LinkedIn page on 26, check size on 4.
Corrections
Email hello@theinvestordatabase.com or use the update form. We act within 5 working days.

How we verify

Questions

How many Series B cybersecurity investors in the US are there?

We list 37 as of November 2026. 29 of the 37 have a fund filing or a dated deal in the last 12 months. The cities with the most are New York (6), Palo Alto (3) and San Francisco (2).

Which Series B cybersecurity investors in the US raised a new fund in the last 12 months?

21 of the 37 have a fund filing dated in the last 12 months. The most recent on this list are Bessemer Venture Partners (Oct 2026), Alpha Partners (Oct 2026) and SYN Ventures (Oct 2026).

What is the typical fund size of Series B cybersecurity investors in the US?

The median fund size on file for this list is $200M, across the 28 firms with a size on an SEC Form D. The fund on file is each firm's main fund, which is not always its newest. The other 9 do not disclose a size there.

How do I contact Series B cybersecurity investors in the US?

The paid file holds 239 named decision-makers across 35 of these 37 and a firm email for 11. We publish the address a firm lists itself, never a personal email. Each free row links to a profile with the firm's website.

Where does the data on Series B cybersecurity investors in the US come from?

35 of the 37 rows have an SEC filing on file (Form D or Form ADV) and 2 were checked on the firm's own website or an official register. Filing date and fund size come from the filing. Stage, sector and check size are our research. Rows on this list were last checked on 7 Nov 2026 at the latest. The whole file is re-verified twice a year.

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