---
title: "37 Series B Cybersecurity Investors in the US (Nov 2026)"
last_updated: "2026-11-07"
rows: "37"
free_rows: "18"
source: "SEC Form D filings and our own research"
canonical: "https://theinvestordatabase.com/lists/series-b-cybersecurity-investors-us/"
---

# 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).

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

## First 18 of 37 Series B cybersecurity investors in the US

| Investor | Type | HQ | Stages (our research) | Focus (our research) | Latest fund or deal | Fund size | Checked | Profile |
|---|---|---|---|---|---|---|---|---|
| Alpha Partners | VC firm | New York, NY | Series B, Growth | Cybersecurity, AI, Developer Tools, Healthtech | New fund, Oct 2026 | $200M (SEC Form D, 2024) | 2026-11-04 | https://theinvestordatabase.com/investors/alpha-partners/ |
| Energy Impact Partners | VC firm | United States (London office) | Seed, Series A, Series B, Growth | Cybersecurity, Energy, Climate Tech, AI | Portfolio news, Nov 2026 | $4.5B (own site) | 2026-11-05 | https://theinvestordatabase.com/investors/energy-impact-partners/ |
| Tribe Capital | VC firm | San Mateo, CA | Seed, Series A, Series B, Growth | Cybersecurity, AI, Crypto and Web3, Generalist | New fund, Oct 2026 | $500M (SEC Form D, 2021) | 2026-11-04 | https://theinvestordatabase.com/investors/tribe-capital/ |
| Translink Capital | VC firm | Palo Alto, CA | Seed, Series A, Series B | Cybersecurity, AI, Developer Tools, Mobility | New fund, Sep 2026 | $174M (SEC Form D, 2021) | 2026-11-05 | https://theinvestordatabase.com/investors/translink-capital/ |
| Madrona | VC firm | Seattle, WA | Pre-seed, Seed, Series A, Series B, Growth | Cybersecurity, AI, Biotech, Consumer | New deal, Oct 2026 | $490M (SEC Form D, 2025) | 2026-11-05 | https://theinvestordatabase.com/investors/madrona/ |
| Evolution | VC firm | New York, NY | Seed, Series A, Series B, Growth | Cybersecurity, AI, Developer Tools, SaaS | New fund, Sep 2026 | $1.2B (SEC Form D, 2026) | 2026-11-04 | https://theinvestordatabase.com/investors/evolution/ |
| Ansa | VC firm | New York, NY | Series A, Series B, Growth | Cybersecurity, AI, Healthtech, Media | New fund, May 2026 | $200M (SEC Form D, 2026) | 2026-11-04 | https://theinvestordatabase.com/investors/ansa/ |
| FLF Accelerate | VC firm | Tampa, FL | Pre-seed, Seed, Series A, Series B | Cybersecurity, AI, Fintech, Media | New fund, Sep 2026 | $5M (SEC Form D, 2026) | 2026-11-04 | https://theinvestordatabase.com/investors/flf-accelerate/ |
| SignalFire | VC firm | San Francisco, CA | Seed, Series A, Series B, Growth | Cybersecurity, AI, Healthtech, Developer Tools | New fund, May 2026 | $357M (SEC Form D, 2021) | 2026-11-04 | https://theinvestordatabase.com/investors/signalfire/ |
| Massive VC | VC firm | Boulder, CO | Seed, Series A, Series B | Cybersecurity, Space, AI, Energy | New fund, May 2026 | $30M (SEC Form D, 2026) | 2026-11-04 | https://theinvestordatabase.com/investors/massive-vc/ |
| SYN Ventures | VC firm | West Palm Beach, FL | Seed, Series A, Series B | Cybersecurity, AI, Defense Tech, Industrial Tech | New fund, Oct 2026 | $300M (SEC Form D, 2022) | 2026-11-04 | https://theinvestordatabase.com/investors/syn-ventures/ |
| Menlo Ventures | VC firm | Menlo Park, CA | Pre-seed, Seed, Series A, Series B, Growth | Cybersecurity, AI, Media, Robotics | New fund, Sep 2026 | $800M (SEC Form D, 2025) | 2026-11-04 | https://theinvestordatabase.com/investors/menlo-ventures/ |
| Westly Capital Partners | VC firm | Menlo Park, CA | Pre-seed, Seed, Series A, Series B, Growth | Cybersecurity, AI, Energy, Industrial Tech | New fund, May 2026 | $500M (SEC Form D, 2026) | 2026-11-04 | https://theinvestordatabase.com/investors/westly-capital-partners/ |
| Dallas Venture Capital I DVC | VC firm | Irving, TX | Seed, Series A, Series B | Cybersecurity, AI, Fintech, Data | New deal, Oct 2026 | $75M (SEC Form D, 2021) | 2026-11-05 | https://theinvestordatabase.com/investors/dallas-venture-capital-i-dvc/ |
| Greenfield Partners | VC firm | New York, NY | Series A, Series B, Growth | Cybersecurity, AI, Deep Tech, Fintech | New fund, Jul 2026 |  | 2026-11-04 | https://theinvestordatabase.com/investors/greenfield-partners/ |
| Variant | VC firm | New York, NY | Pre-seed, Seed, Series A, Series B, Growth | Cybersecurity, Fintech, AI, Crypto and Web3 | New fund, Sep 2026 | $250M (SEC Form D, 2025) | 2026-11-04 | https://theinvestordatabase.com/investors/variant/ |
| Atlas Ventures | VC firm | Chicago, IL | Seed, Series A, Series B | Cybersecurity, Logistics, AI, Industrial Tech | New fund, Sep 2026 | $23M (SEC Form D, 2026) | 2026-11-04 | https://theinvestordatabase.com/investors/atlas-ventures/ |
| Ten Eleven Ventures | VC firm | United States | Seed, Series A, Series B, Growth | Cybersecurity, AI, SaaS | New deal, Sep 2026 |  | 2026-11-05 | https://theinvestordatabase.com/investors/ten-eleven-ventures/ |

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

Get all 37 investors and 239 named contacts, $49, one-time: https://theinvestordatabase.com/buy/list/series-b-cybersecurity-investors-us
This page: https://theinvestordatabase.com/lists/series-b-cybersecurity-investors-us/

## 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: 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.
- 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.

## 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.