Jon Callas
Angel investor in San Jose
San Jose, California
Jon Callas, Angel investor in San Jose is an active investor based in San Jose, California. This profile covers what Jon Callas backs, at which stage, and how founders can reach out in 2026.
Mr. Jon Callas is a Co-Founder of Dark Mail Alliance. Mr. Callas is an Angel Investor. He serves as Advisor at Titaniam. He also serves as Advisor at Ten Eleven Ventures. He was a Co-Founder & served as the Chief Technology Officer at Silent Circle. Prior to joining Entrust, Callas co-founded PGP Corporation which specialized in email and data encryption software. Over the course of more than fifteen years, Callas held leadership functions including CTO and CSO. Most recently, he also served as an operating system security expert with Apple. Additionally, he has held leadership positions with corporations including Wave Systems Corporation, Digital Equipment Corporation and Counterpane Internet Security Inc. He has also authored several Internet Engineering Task Force (IETF) standards including OpenPGP, DKIM, and ZRTP. He serves as an Advisor at ten Eleven Ventures.
- Investor type
- Angel
- Stages
- Early Stage Venture
- Invests in
- Artificial IntelligenceHealthcare & BiotechDigital Health & HealthTechBiotech & PharmaMedTech & Medical DevicesSaaS & EnterpriseConsumer & RetailClimate & Energy
- Location
- San Jose, California
- Typical check
- $500K
- Past investments
- 3
Notable investments
RipcordHow to reach Jon Callas
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Round Funded. "Jon Callas." Round Funded investor database, updated September 8, 2026.
Stable URL, it will not change: https://www.roundfunded.com/en/investor/jon-callas
Frequently Asked Questions
What does Jon Callas invest in?
Jon Callas invests in Artificial Intelligence, Healthcare & Biotech, Digital Health & HealthTech and Biotech & Pharma, typically at Early Stage Venture. Match your sector and stage, then reach out with a personalized pitch.
What stage does Jon Callas invest at?
Jon Callas typically invests at Early Stage Venture. Lead with traction that fits the stage when you reach out.
What is Jon Callas's typical check size?
Jon Callas typically writes checks around $500K. 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.
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