Pebblebed
UnclaimedAt a Glance
- Check Size
- $10K – $500K
- Stage
- Pre-Seed, Seed, Series A
- Sectors
- AI, Enterprise
- HQ
- San Francisco, CA
About Pebblebed
Pebblebed is a San Francisco-based seed-stage venture capital firm founded by former Facebook and OpenAI engineers who bring deep technical expertise to their investment approach. The firm's founding team's background at leading technology companies provides them with unique insights into infrastructure and AI technologies, enabling them to identify and evaluate cutting-edge technical opportunities.
The firm focuses on pre-seed, seed, and Series A investments in artificial intelligence and enterprise infrastructure companies. Pebblebed's investment thesis leverages their founders' firsthand experience building large-scale systems at Facebook and working on frontier AI research at OpenAI. This technical background allows them to assess complex infrastructure and AI companies that other generalist investors might struggle to evaluate properly.
While specific portfolio details remain limited, Pebblebed's positioning reflects the growing trend of operator-led venture capital firms, where former engineers and executives from major technology companies apply their domain expertise to venture investing. Their focus on infrastructure investments positions them well in a market where enterprise infrastructure and AI tooling represent significant growth opportunities.
Investment Thesis
“Seed-stage investments in AI and infrastructure companies, leveraging deep technical expertise from former Facebook and OpenAI engineers.”
Sector Focus
Investment Stage
Notable Portfolio Companies
Fund History
Pebblebed has raised three funds since 2022, each roughly four times the size of the last. Pebblebed Fund I, LP filed a Form D in July 2022 reporting $10 million sold from a single investor, then amended in July 2023 to $28.1 million across 64 investors, with the offering amount left indefinite.
Pebblebed Fund II, LP filed in August 2024 against a $125 million offering. Pebblebed Fund III, LP filed in July 2026 against a $200 million offering, with no capital reported sold at the filing date. The executive officers named on the Fund II offering are Tammie Siew, Keith Adams, Pam Vagata and Luke Byrne, all filing from San Francisco. The firm says it makes roughly twenty investments per fund and leads its rounds, a concentrated posture for a technically specialized seed manager. Pebblebed does not publish assets under management or a founding date on its own site.
SEC Fund Filings
- Vehicles filed, last 24 months
- 1
- Latest filing
Pebblebed filed a Form D for 1 fund vehicle between Sep 26, 2024 and Sep 25, 2026.
| Fund vehicle | Source |
|---|---|
| Pebblebed Fund III, LP | SEC Form D, filed |
A Form D is the notice a fund files with the SEC when it raises money in a private offering. Feeder funds, parallel funds and SPVs each file their own, so the count measures filing activity, not the number of flagship funds.
Source: SEC EDGAR Form D filings for pooled investment funds, original filings only (amendments excluded). Our filing data starts Jul 1, 2024. Vehicles are matched to Pebblebed by fund name and checked against the sponsor address and named principals on each filing; offering amounts are not shown. Each “SEC Form D” link opens an EDGAR full-text search for that vehicle’s exact name, where the filing itself is listed. See every new fund filing on the Form D Radar.
Team (1)
Frequently Asked Questions
What stage does Pebblebed invest at?
Pebblebed primarily invests at the Pre-Seed, Seed, Series A stages. This means they focus on companies that are at the earliest idea or prototype phase.
Where is Pebblebed located?
Pebblebed is headquartered in San Francisco, CA. Many of their portfolio companies are also based in this region, though they invest across geographies.
What sectors does Pebblebed focus on?
Pebblebed focuses on investments in AI, Enterprise. Their portfolio reflects deep expertise and networks within these sectors.
What is Pebblebed's typical check size?
Pebblebed's typical investment check size ranges from $10K to $500K. Actual amounts may vary based on the stage, sector, and specific opportunity.
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