Jim Clark
About Jim Clark
Jim Clark is a computer scientist and serial founder based in Palm Beach. He co-founded Silicon Graphics in 1982. The company built high-performance workstations that displayed 3-D images in real time. Before that he was an associate professor at Stanford. His Ph.D. in computer science is from the University of Utah.
In 1994 he co-founded Netscape Communications. He also started Healtheon, which became WebMD, as well as myCFO and Shutterfly. Crunchbase says he has chaired Silicon Graphics, Netscape, Shutterfly, Healtheon, DNA Sciences and WebMD.
In 2017 TechCrunch reported that he was self-funding CommandScape, a home-automation and building-control startup. Crunchbase also lists him as chairman and co-founder of Beyond Identity.
Crunchbase lists 17 personal investments for Clark, including Positron and Beyond Identity. It shows him in the Series B and Series C rounds of Beyond Identity. It also lists Shutterfly as an exit. The public profile does not give check sizes, dates for most of these deals, or a count of early-stage angel checks.
Clark's best-documented AI investment is Positron AI, a Reno, Nevada company that builds hardware and software for AI inference. Positron announced an $875 million Series C at a $5 billion post-money valuation in September 2026. The round came in two tranches. The first was a $375 million Series C. The second was a Series C-1 of up to $500 million, anchored by NEA and Clark. Crunchbase marks him as a lead investor in the round.
Thomas Jermoluk, from Clark's office, joined Positron's board as part of the financing. In the announcement Clark said Positron's power consumption, cost and density suit inference for large language models with trillions of parameters.
Clark's one public AI lead is a late-stage round in AI inference hardware. His earlier companies were in computer graphics, internet software, healthcare technology, consumer internet and financial services. He has not publicly stated a typical check size, a target stage or a list of what he looks for in founders. Those details are left out here.
- Positron AI: AI inference hardware and software built on commodity memory. Clark co-led the Series C-1 with NEA in 2026.
- Beyond Identity: Identity and security company. Crunchbase lists Clark as chairman and co-founder, and shows him in its Series B and Series C rounds.
- Shutterfly: Photo products company that Clark co-founded. Crunchbase lists it as an exit.
- Silicon Graphics: 3-D graphics workstation maker that Clark co-founded in 1982.
- Netscape Communications: Browser company that Clark co-founded in 1994.
- Healtheon (later WebMD): Healthcare internet company that Clark founded.
- crunchbase.com/person/james-h-clark
- finance.yahoo.com/technology/ai/articles/positron-ai-raises-875-millio
- citybiz.co/article/901809/nea-jim-clark-join-positron-ais-875m-round-t
- finance.yahoo.com/technology/ai/articles/positron-ai-875m-bet-commodit
- techcrunch.com/2017/08/22/billionaire-netscape-founder-jim-clark-is-ba
- encyclopedia.com/education/economics-magazines/clark-jim-0
Investing activity
Jim Clark appears in 1 AI deal tracked by the AI Lounge deals desk, rounds totalling $875M, and led 1 of them. The rounds are mostly Series C, with a median round size of $875M. The most recent is Positron (Series C, $875M, Sep 2026).
Jim Clark most often invests alongside Valor Equity Partners, Atreides Management, Andra Capital and NEA, and the companies they back on AI Lounge are mostly in AI inference chips.
Deals
Frequently asked questions about Jim Clark
Does Jim Clark invest in AI startups?
Yes. He co-led the Series C-1 of Positron AI, an AI inference chip company, with NEA. The round was part of an $875 million financing announced in September 2026.
What is Jim Clark's check size as an angel investor?
It is not public. None of the sources found state a check size or range for his personal investments.
What companies did Jim Clark found?
He co-founded Silicon Graphics and Netscape Communications. He also started Healtheon (which became WebMD), myCFO and Shutterfly. More recently he started CommandScape and is listed as co-founder of Beyond Identity.
What stage does Jim Clark invest in?
His only documented AI lead is a Series C-1 growth round. No source states a preferred stage, so founders should not assume he invests at pre-seed or seed.
How can founders contact Jim Clark?
No personal website, LinkedIn or X profile was confirmed. The Positron announcement names Thomas Jermoluk of Jim Clark Office, who joined that company's board.
Is Jim Clark an angel investor?
Yes. Jim Clark invests personally as an angel.
What AI companies has Jim Clark invested in?
Jim Clark's AI investments include Positron. The 1 round on AI Lounge are listed on this page with amounts, dates and co-investors.
Where is Jim Clark based?
Jim Clark is based in Palm Beach, US.
What stage does Jim Clark invest at?
In the rounds tracked on AI Lounge, Jim Clark has invested at Series C, with a median round of $875M. Jim Clark led 1 of those rounds.
Who does Jim Clark co-invest with?
Jim Clark's most frequent co-investors on AI Lounge are Valor Equity Partners (1 deal), Atreides Management (1 deal), Andra Capital (1 deal), NEA (1 deal) and SemiAnalysis Capital (1 deal).