Tanis Venture Management Research
Source Caveat
The firm's own website (tanisventures.com) is a GoDaddy "Coming Soon" placeholder with no content, no portfolio page and no team page. Everything below comes from press releases, portfolio-company announcements, and third-party investor databases (Caplight, Startup Intros, ConnectSafely, PitchBook and Preqin summaries). Confidence is moderate on thesis and low on check size, fund size and AUM, none of which are disclosed anywhere we could verify.
Investment Thesis
Tanis Venture Management, LLC is a New York City venture firm founded in 2019. Its stated approach is to invest in early-stage companies that have access to non-dilutive R&D funding (for example SBIR/STTR grants and government contracts) and to work closely with scientists and founders to commercialize deep technology. Its two visible verticals are biotech/healthcare and defense technology. Jack Seaver describes the firm as an early-stage venture capital firm with a focus on early-stage healthcare and defense companies. Databases also list B2B, information technology and life sciences as target sectors.
Stage Focus
Seed and Series A. The earliest verifiable deal is a Dive Technologies round in December 2020 that Tanis led. Later deals (Bounce Imaging, Corner Therapeutics, CND Life Sciences, Seasats) were participations in rounds led by other investors, and one 2024 deal for Corner Therapeutics was reported as a grant-style or other financing alongside the Series A.
Check Size
Not disclosed. Dive Technologies' $4M round in 2020 was led by Tanis, which suggests lead checks in the low single-digit millions at most. No check range is stored.
Lead Tendency
Both. Tanis led Dive Technologies' $4M equity round (December 2020), but is listed as a participant, not the lead, in Bounce Imaging's Series A prime (led by R42 Group and Good Growth Capital, May 2022), Corner Therapeutics' $54M Series A (led by Ziff Capital Partners, April 2024), and Seasats' $20M Series A (led by Konvoy Ventures, February 2026).
Recent Activity
- February 2026: participated in Seasats' $20M Series A (autonomous surface vessels for defense, led by Konvoy Ventures, with Shield Capital, DNS Capital, Techstars, Crumpton Ventures, Dorado Group).
- May 2025: listed as an investor in CND Life Sciences (Series A per Caplight; CND also announced a Series Seed 3 in April 2023 that names Jack Seaver as a director).
- April 2024: participated in Corner Therapeutics' $54M Series A (vaccine and immunology company).
- February 2022: portfolio company Dive Technologies was acquired by Anduril Industries; Tanis, Mill Town Capital and VTC Ventures were the selling investors.
The firm appears to be an active, low-volume investor: databases count roughly four to seven portfolio companies and about one new deal per year. Fund status is treated as actively deploying on the strength of the February 2026 deal, but no fund size has been published.
Portfolio Highlights
- Dive Technologies (subsea robotics, Boston): Tanis led the 2020 equity round; acquired by Anduril Industries in February 2022. This is the firm's known exit.
- Bounce Imaging: throwable tactical camera; Series A prime in 2022; Jack Seaver is a board observer.
- CND Life Sciences: neurodegenerative disease diagnostics; Jack Seaver sits on the board.
- Corner Therapeutics: vaccines and immune-system therapeutics; Series A 2024.
- Seasats: long-endurance autonomous surface vessels for defense; Series A 2026.
- Rampart Communications and Photonics657: Jack Seaver serves on both boards, so Tanis likely holds positions, but no round announcements were found.
Team
- Jack Seaver, Managing Partner and Co-Founder: runs day-to-day operations and works with portfolio companies on strategy, operations and financing. Director at CND Life Sciences, Rampart Communications and Photonics657, board observer at Bounce Imaging, and previously on the Dive Technologies board. Earlier operating roles at Bay Area startups and at DCI Group; BA Amherst, MBA Stanford GSB.
- Alexander Seaver, Co-Founder and Managing Partner: co-founded Stadium Capital Management in 1997; previously a partner at Interwest Venture Management.
- Bradley Kent, Co-Founder: co-founded Stadium Capital Management and served as a portfolio manager there.
Decision Process
Partnership of three co-founders, with Jack Seaver the operating partner on most boards. No formal committee structure is documented.
Founder Preferences
Scientist-founders and technical teams with commercially relevant research, and companies that can fund development through grants and government contracts before or alongside equity. Defense companies in the portfolio carry real government traction (Seasats reports over $100M in US government contracts).
Geographic Focus
US-wide. Headquartered in New York City; portfolio spans Boston (Dive), San Diego (Seasats) and other US hubs. Co-investors skew toward regional and sector specialists such as Mill Town Capital, VTC Ventures, Konvoy Ventures, Shield Capital and Ziff Capital Partners.
Gaps
No official website content, fund size, AUM, check range or contact emails were found. The Business Wire release on the Dive exit could not be fetched directly; its content was confirmed through WSJ, Janes and Caplight snippets.