William Simpson
Managing General Partner at Yellowdog Capital
Seal Beach, California
William Simpson, Managing General Partner at Yellowdog Capital is an active investor based in Seal Beach, California. This profile covers what William Simpson backs, at which stage, and how founders can reach out in 2026.
William Simpson is Managing General Partner at Yellowdog Capital and owner of tradingipos.com.
William Simpson invests in Fintech, SaaS & Enterprise and Artificial Intelligence, typically at Seed and Series A.
- Investor type
- VC
- Stages
- SeedSeries A
- Invests in
- FintechSaaS & EnterpriseArtificial Intelligence
- Location
- Seal Beach, California
- Typical check
- $625K
How to reach William Simpson
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About this profile
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Cite this page
Round Funded. "William Simpson." Round Funded investor database, updated November 3, 2026.
Stable URL, it will not change: https://www.roundfunded.com/en/investor/william-simpson
Frequently Asked Questions
Who is William Simpson?
William Simpson, Managing General Partner at Yellowdog Capital is an active investor based in Seal Beach, California. William Simpson invests in Fintech, SaaS & Enterprise and Artificial Intelligence, typically at Seed and Series A.
What does William Simpson invest in?
William Simpson invests in Fintech, SaaS & Enterprise and Artificial Intelligence, typically at Seed and Series A. Match your sector and stage, then reach out with a personalized pitch.
What stage does William Simpson invest at?
William Simpson typically invests at Seed and Series A. Lead with traction that fits the stage when you reach out.
What is William Simpson's typical check size?
William Simpson typically writes checks around $625K. Use it as a signal for whether your raise fits their stage.
How do founders reach investors like this?
Round Funded lists active investors with verified, professional contact details for signed-up founders. Filter by sector, stage and location, then send a personalized pitch from your own inbox.
What is Round Funded?
Round Funded is an investor database and outreach platform for startup founders. It lists 60,000+ active investors with verified contacts, filtered to recent investment activity, and lets founders send personalized pitches from their own Gmail, track replies, and share a free Data Room. Round+ starts at $99 per month with a 3-day trial.