126 Series B AI investors in the US
We list 126 Series B AI investors in the US as of November 2026: 123 have an SEC filing on file and 3 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 (21), San Francisco (17) and Menlo Park (9).
Top 5 Series B AI 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.
Alpha Partners
Type: VC firm · HQ: New York, NY · Stages: Series B, Growth · Focus: AI, Developer Tools, Healthtech, Cybersecurity · 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 AI as a focus; backs Series B, growth-stage; names the US as where it invests; 8 named decision-makers on file.
Greycroft
Type: VC firm · HQ: New York, NY · Stages: Series A, Series B, Growth · Focus: AI, Industrial Tech, Defense Tech, Healthtech · Latest activity: New deal, Oct 2026 · Fund size on file: $600M (SEC Form D, 2022)
Dated new deal in Oct 2026; $600M fund on file (SEC Form D, 2022); states AI as a focus; backs Series A, Series B, growth-stage; names the US as where it invests; 5 named decision-makers on file.
Energy Impact Partners
Type: VC firm · HQ: United States (London office) · Stages: Seed, Series A, Series B, Growth · Focus: AI, Energy, Climate Tech, Cybersecurity · 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 AI as a focus; backs seed, Series A, Series B; names the US as where it invests; 8 named decision-makers on file.
Tribe Capital
Type: VC firm · HQ: San Mateo, CA · Stages: Seed, Series A, Series B, Growth · Focus: AI, Cybersecurity, 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 AI as a focus; backs seed, Series A, Series B; names the US as where it invests; 8 named decision-makers on file.
Kleiner Perkins
Type: VC firm · HQ: Menlo Park, CA · Stages: Pre-seed, Seed, Series A, Series B, Growth · Focus: AI, Fintech, Proptech, Mobility · Latest activity: New fund, Aug 2026 · Fund size on file: $995M (SEC Form D, 2026)
Latest fund filing dated Aug 2026; $995M fund on file (SEC Form D, 2026); states AI as a focus; backs pre-seed, seed, Series A; names the US as where it invests; 2 named decision-makers on file.
First 25 of 126 Series B AI investors in the US
| Investor | Type | HQ | Stagesour research | Focusour research | Latest fund or deal | Fund sizeas filed or stated | Checked | Contacts |
|---|---|---|---|---|---|---|---|---|
| Alpha Partners | VC firm | New York, NY | Series B, Growth | AI, Developer Tools, Healthtech, Cybersecurity | New fund, Oct 2026 | $200M (SEC Form D, 2024) | 4 Nov 2026 | 8 names, firm email · Unlock |
| Greycroft | VC firm | New York, NY | Series A, Series B, Growth | AI, Industrial Tech, Defense Tech, Healthtech | New deal, Oct 2026 | $600M (SEC Form D, 2022) | 4 Nov 2026 | 5 names · Unlock |
| Energy Impact Partners | VC firm | United States (London office) | Seed, Series A, Series B, Growth | AI, Energy, Climate Tech, Cybersecurity | Portfolio news, Nov 2026 | $4.5B (own site) | 5 Nov 2026 | 8 names · Unlock |
| Tribe Capital | VC firm | San Mateo, CA | Seed, Series A, Series B, Growth | AI, Cybersecurity, Crypto and Web3, Generalist | New fund, Oct 2026 | $500M (SEC Form D, 2021) | 4 Nov 2026 | 8 names, firm email · Unlock |
| Kleiner Perkins | VC firm | Menlo Park, CA | Pre-seed, Seed, Series A, Series B, Growth | AI, Fintech, Proptech, Mobility | New fund, Aug 2026 | $995M (SEC Form D, 2026) | 4 Nov 2026 | 2 names · Unlock |
| Translink Capital | VC firm | Palo Alto, CA | Seed, Series A, Series B | AI, Developer Tools, Mobility, B2B | New fund, Sep 2026 | $174M (SEC Form D, 2021) | 5 Nov 2026 | 8 names, firm email · Unlock |
| Bison Ventures | VC firm | San Francisco, CA | Pre-seed, Seed, Series A, Series B | AI, Healthtech, Energy, Biotech | New fund, Oct 2026 | $160M (SEC Form D, 2025) | 4 Nov 2026 | 2 names, firm email · Unlock |
| Madrona | VC firm | Seattle, WA | Pre-seed, Seed, Series A, Series B, Growth | AI, Biotech, Consumer, Deep Tech | New deal, Oct 2026 | $490M (SEC Form D, 2025) | 5 Nov 2026 | 8 names · Unlock |
| Autotech Ventures | VC firm | Menlo Park, CA | Pre-seed, Seed, Series A, Series B | AI, Mobility, Logistics, Fintech | New fund, Aug 2026 | $25M (SEC Form D, 2026) | 4 Nov 2026 | 8 names · Unlock |
| How Women Invest | VC firm | Oakland, CA | Pre-seed, Seed, Series A, Series B | AI, Healthtech, B2B, Climate Tech | New fund, Sep 2026 | $12M (SEC Form D, 2026) | 4 Nov 2026 | 8 names · Unlock |
| Prudence. | VC firm | New York, NY | Series A, Series B | AI, Proptech, Robotics, Developer Tools | New fund, Aug 2026 | $150M (SEC Form D, 2022) | 4 Nov 2026 | 3 names · Unlock |
| Evolution | VC firm | New York, NY | Seed, Series A, Series B, Growth | AI, Cybersecurity, Developer Tools, SaaS | New fund, Sep 2026 | $1.2B (SEC Form D, 2026) | 4 Nov 2026 | 8 names · Unlock |
| Lightspeed Venture Partners | VC firm | Menlo Park, CA | Seed, Series A, Series B, Growth | AI, Healthtech, Gaming, SaaS | New fund, Jul 2026 | $1.2B (SEC Form D, 2024) | 4 Nov 2026 | 8 names · Unlock |
| G2 Venture Partners | VC firm | Portola Valley, CA | Series B, Growth | AI, Industrial Tech, Mobility, Energy | New deal, Aug 2026 | $53M (SEC Form D, 2026) | 4 Nov 2026 | 8 names, firm email · Unlock |
| Ansa | VC firm | New York, NY | Series A, Series B, Growth | AI, Cybersecurity, Healthtech, Media | New fund, May 2026 | $200M (SEC Form D, 2026) | 4 Nov 2026 | 4 names, firm email · Unlock |
| Greylock | VC firm | San Francisco, CA | Seed, Series A, Series B, Growth | AI | New fund, Jun 2026 | $10.5B (SEC Form ADV) | 5 Nov 2026 | LinkedIn page · Unlock |
| Geodesic | VC firm | Foster City, CA | Series B, Any stage | AI, Developer Tools, Fintech, B2B | New deal, Oct 2026 | $500M (SEC Form D, 2021) | 5 Nov 2026 | 8 names, firm email · Unlock |
| FLF Accelerate | VC firm | Tampa, FL | Pre-seed, Seed, Series A, Series B | AI, Fintech, Media, B2B | New fund, Sep 2026 | $5M (SEC Form D, 2026) | 4 Nov 2026 | 8 names · Unlock |
| SignalFire | VC firm | San Francisco, CA | Seed, Series A, Series B, Growth | AI, Healthtech, Developer Tools, B2B | New fund, May 2026 | $357M (SEC Form D, 2021) | 4 Nov 2026 | 8 names · Unlock |
| Massive VC | VC firm | Boulder, CO | Seed, Series A, Series B | AI, Space, Energy, Cybersecurity | New fund, May 2026 | $30M (SEC Form D, 2026) | 4 Nov 2026 | 3 names · Unlock |
| NIYA Partners | VC firm | Miami, FL | Series A, Series B, Growth | AI, Fintech, Insurtech, Generalist | New fund, May 2026 | $11M (SEC Form D, 2026) | 4 Nov 2026 | LinkedIn page · Unlock |
| Altra | VC firm | New York, NY | Series B, Late stage | AI, SaaS, Hardware | New fund, May 2026 | 4 Nov 2026 | 1 name, firm email · Unlock | |
| Access Ventures | VC firm | New York, NY | Series B, Growth, Late stage | AI, Generalist, SaaS, Deep Tech | New fund, Aug 2026 | $6M (SEC Form D, 2026) | 4 Nov 2026 | 2 names · Unlock |
| SYN Ventures | VC firm | West Palm Beach, FL | Seed, Series A, Series B | AI, Cybersecurity, Defense Tech, Industrial Tech | New fund, Oct 2026 | $300M (SEC Form D, 2022) | 4 Nov 2026 | 8 names · Unlock |
| IVP: Venture capital for the Exceptional | VC firm | Menlo Park, CA | Series B, Growth | AI, Healthtech, Developer Tools, SaaS | New fund, Oct 2026 | $60M (SEC Form D, 2026) | 4 Nov 2026 | 8 names · Unlock |
You are seeing 25 of 126. The full list adds 101 more investors and 737 named decision-makers.
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How these 126 break down
By US state
| US state | On this list | Share |
|---|---|---|
| California | 49 | 39% |
| New York | 25 | 20% |
| Florida | 7 | 6% |
| Illinois | 6 | 5% |
| Massachusetts | 6 | 5% |
| Colorado | 4 | 3% |
| Washington | 3 | 2% |
| Maryland | 3 | 2% |
| Texas | 2 | 2% |
| Tennessee | 2 | 2% |
By type
| Type | On this list | Share |
|---|---|---|
| VC firm | 123 | 98% |
| Corporate VC | 2 | 2% |
Method and limits
- Source
- 123 of the 126 rows carry an SEC filing (Form D or Form ADV). All 126 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 AI 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 126 rows: stage 126, sector 126, fund size 108, website 126. In the paid file: named decision-makers on 118 rows, firm email on 45, LinkedIn page on 80, check size on 10.
- Corrections
- Email hello@theinvestordatabase.com or use the update form. We act within 5 working days.
Questions
How many Series B AI investors in the US are there?
We list 126 as of November 2026. 83 of the 126 have a fund filing or a dated deal in the last 12 months. The cities with the most are New York (21), San Francisco (17) and Menlo Park (9).
Which Series B AI investors in the US raised a new fund in the last 12 months?
61 of the 126 have a fund filing dated in the last 12 months. The most recent on this list are IVP: Venture capital for the Exceptional (Oct 2026), Bison Ventures (Oct 2026) and Overlap Holdings (Oct 2026).
What is the typical fund size of Series B AI investors in the US?
The median fund size on file for this list is $102M, across the 91 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 35 do not disclose a size there.
How do I contact Series B AI investors in the US?
The paid file holds 737 named decision-makers across 118 of these 126 and a firm email for 45. 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 AI investors in the US come from?
123 of the 126 rows have an SEC filing on file (Form D or Form ADV) and 3 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.
Broader lists
AI venture capital firms in the US (1,112)Series B investors in the US (165)Series B AI investors (204)
Related lists
Seed AI investors in the US (724)Pre-seed AI investors in the US (403)Series A AI investors in the US (280)Growth-stage AI investors in the US (162)Series B SaaS investors in the US (108)Series B healthtech investors in the US (69)Series B fintech investors in the US (59)Series B deep tech investors in the US (41)Series B cybersecurity investors in the US (37)Series B medtech investors in the US (36)Series B biotech investors in the US (34)Series B energy investors in the US (29)Series B industrial tech investors in the US (29)Series B consumer investors in the US (29)Series B hardware investors in the US (28)Series B B2B investors in the US (27)Series B climate tech investors in the US (27)Series B developer tools investors in the US (21)
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