John Jack
Venture investor in San Francisco
San Francisco, California
John Jack, Venture investor in San Francisco is an active investor based in San Francisco, California. This profile covers what John Jack backs, at which stage, and how founders can reach out in 2026.
- Investor type
- VCInvestor
- Stages
- Seed
- Invests in
- CybersecuritySaaS & EnterpriseHardware & Deep Tech
- Location
- San Francisco, California
- Typical check
- $250K
- Past investments
- 3
Notable investments
CipherCloudoak9How to reach John Jack
Angels and operators like John Jack reply to specific, personalized notes that show real traction, not mass blasts. Build a verified list, write a note that fits their thesis, and track replies, all on Round Funded Accelerator.
Connect with John Jack
Frequently Asked Questions
What does John Jack invest in?
John Jack invests in Cybersecurity, SaaS & Enterprise and Hardware & Deep Tech, typically at Seed. Match your sector and stage, then reach out with a personalized pitch.
What stage does John Jack invest at?
John Jack typically invests at Seed. Lead with traction that fits the stage when you reach out.
What is John Jack's typical check size?
John Jack typically writes checks around $250K. Use it as a signal for whether your raise fits their stage.
How do I contact John Jack?
Unlock John Jack's verified email on Round Funded Accelerator and send a personalized pitch. We surface only deliverable contacts so your outreach lands.