Brian Singerman

Background

Brian Singerman is an American venture capitalist and partner emeritus at Founders Fund, the San Francisco-based venture capital firm founded by Peter Thiel ¹². He graduated from Stanford University in 1999 with a B.S. in Computer Science ¹.

After Stanford, Singerman joined There, Inc., a virtual-world online startup, as a software engineer ¹³. In 2004, he moved to Google, where he spent four years as an engineer and executive ¹³. At Google, he founded iGoogle, the personalized web portal product ¹³. During his time at Google, Singerman launched his first investment vehicle, a $1 million fund called the XGYC Fund (short for “ex-Google, Y Combinator”), which invested in early Y Combinator companies starting around 2007 ¹³.

In 2008, Singerman joined Founders Fund as a principal, becoming a partner in 2011 ³⁴. Over a 16-year tenure, he became one of the firm’s most prolific investors, generating some of Founders Fund’s largest returns ²⁵. He was ranked #5 on the 2017 Forbes Midas List, up from #36 the prior year, driven largely by the Stemcentrx exit ⁶.

On December 3, 2024, Singerman announced his transition from general partner to partner emeritus at Founders Fund, stating he would continue as an investor and strategic advisor while seeking better work-life balance ²⁵. In July 2025, he and Lee Linden (co-founder of Quiet Capital) announced they were raising over $500 million for a new fund called GPx, with Peter Thiel expected to contribute a significant portion of the capital ⁷. GPx will invest approximately 20% of its capital into funds managed by emerging seed-stage VCs, with the remaining 80% going toward co-leading Series B rounds in those managers’ breakout portfolio companies ⁷⁸.

Stated Thesis

(Self-reported: These represent what Singerman says publicly about his investing approach. See Inferred Thesis for analysis of actual investment behavior.)

Singerman describes himself as sector-agnostic and conviction-driven. On the 20VC podcast, he stated: “My expertise is in the founders, the execution of founders, the strategy and the moats that these companies have. And I think that that just scales across all sectors” ⁹.

He has publicly described venture capital as purely about upside maximization: “Venture capital to me is purely a game of upside maximization. And while this may get me in trouble, I actually don’t. Downside minimization is completely unimportant to me” ⁹.

Singerman has said he does not look for consensus validation from other VCs: “The way you make money in venture capital is by backing the truck in and being correct. I’m not looking for validation from other VC firms at all. I’m not interested in marking up a portfolio of companies. I’m interested in these companies being very large and having impact” ⁹.

He has emphasized the importance of early-stage relationships: “Entrepreneurs love when an investor is willing to take an early bet on them and be right” ⁹.

On founder selection, Singerman has said: “When you find a phenomenal founder, you back them regardless of what they are doing” ¹⁰.

Inferred Thesis

Based on 22 verified investments listed below, Singerman’s actual investment behavior reveals a concentrated, high-conviction approach focused on frontier technology companies operating in large, often regulated markets.

Sector distribution (22 verified investments): 6 biotech/life sciences (27%), 5 defense/government technology (23%), 4 AI/data infrastructure (18%), 3 fintech (14%), 2 consumer internet (9%), 2 other/hard-tech (9%).

Stage distribution: Singerman invests across the full spectrum from seed to growth. His highest-profile investments (Anduril, Stemcentrx, SpaceX) involved multiple rounds of follow-on, with Founders Fund writing checks as large as $400M into Anduril across rounds ¹¹. He has also led seed rounds, such as Anduril’s $17.5M seed in 2017 ¹².

Founder profile patterns: Singerman gravitates toward technical founders building in deeply complex domains. He has explicitly compared Palmer Luckey to Elon Musk as a technologist-visionary ¹⁰. His portfolio skews toward founders with deep domain expertise in regulated or hard-tech industries (cancer therapeutics, defense systems, rocket engineering).

Co-investor patterns: As a Founders Fund partner, Singerman frequently co-invested with the firm’s other partners, particularly Peter Thiel. Notable co-investors across his portfolio include Sequoia Capital (Airbnb, Scale AI), Andreessen Horowitz (Anduril), and General Catalyst (Affirm).

Notable gaps between stated and actual thesis: While Singerman describes himself as sector-agnostic, his portfolio reveals strong concentrations in biotech (27%) and defense tech (23%) – sectors that most VCs avoid entirely. His “agnostic” framing understates a clear revealed preference for regulated, capital-intensive, technically complex domains where most venture firms lack the expertise or risk appetite to invest.

Portfolio

This table represents a partial view of Singerman’s portfolio. Analysis sources estimate approximately 65 active investments total ¹⁵. Many investments were made through Founders Fund vehicles and individual deal attribution is not always publicly disclosed. Years marked with ~ are approximate, based on founding year or earliest reported connection.

In Their Own Words

On the Stemcentrx due diligence process, Singerman said: “We weren’t space experts and wouldn’t have done SpaceX if Elon wasn’t running it. This was similar for us.” He also noted: “Scientists are usually very conservative, but we knew that Stemcentrx really had something when these oncologists told us, ‘Well, it won’t obviously not work.’” ¹⁴

On how Founders Fund operates internally: “We’ve tried to have Monday partner meetings…it just doesn’t work for us” ⁹.

On the investment decision process: “Somebody who sees the deal, somebody who brings in the deal has to have enough conviction to at least get the rest of the team to take a look” ⁹.

On business fundamentals: “So especially at the later stage, even if, let’s say, somebody like me has a great gut feel, if the business side doesn’t also check out, we’re probably not making that investment” ⁹.

On the importance of both technical and business talent: “You need just as good business people on your team as you do technology people in order to win” ¹⁰.

On founder relationships: “The only way to get ahead of growth is to invest in a relationship with the founder” ¹⁰.

On his core job: “For my job at this fund is to generate massive returns. And for our fund, you simply have to invest in the world’s most important companies in order to generate those returns” ⁹.

What Founders Say

No independently sourced founder testimonials found. Singerman is widely described as a board director at Affirm, Oscar Health, Postmates, Cloud9, Emerald Therapeutics, Solugen, and Long-Term Stock Exchange, and as a board observer at Airbnb, Forward, Modern Health, and Wish ³, suggesting active post-investment engagement across his portfolio. However, no direct founder quotes about working with Singerman could be independently verified at this time.

Connections

• Board director, Affirm — alongside Max Levchin (CEO & Co-Founder) ³
• Board director, Oscar Health — alongside Mario Schlosser (Co-Founder & CEO) ³
• Board director, Postmates — prior to Uber acquisition in 2020 ³
• Board director, Stemcentrx — prior to AbbVie acquisition in 2016 ¹⁴
• Board director, Solugen — current ³
• Board director, Long-Term Stock Exchange — alongside Eric Ries (CEO & Founder) ³
• Board observer, Airbnb — ¹
• Board observer, Anduril Industries — alongside Palmer Luckey (CEO & Founder) ³
• Board observer, Modern Health — current ³
• Former Google engineer (2004-2008) — founded iGoogle product ¹³
• Co-founder, GPx — with Lee Linden (ex-Quiet Capital), Peter Thiel as major LP ⁷⁸
• Frequent co-investor with Peter Thiel — via Founders Fund across SpaceX, Anduril, and others ²⁵

Sources