Joule Ventures
UnclaimedAt a Glance
- Check Size
- $1M – $3M
- Stage
- Pre-Seed, Seed, Series A, Series B+
- Sectors
- Enterprise, Cybersecurity, SaaS
- HQ
- New York, NY
About Joule Ventures
Joule Ventures is a first-check fund for Israeli management teams commercializing enterprise-grade solutions in U.S. markets. It invests at pre-seed and seed and follows into Series A and later, and its published sector labels are DevOps, cybersecurity, fintech, AI, data enablement and software, categories that some directory records have mistakenly carried as portfolio company names. Brian Rosenzweig is a co-founding partner.
The firm runs a deliberate partner-only model: three partners, no associates fronting deals, operating from Tel Aviv, New York and Atlanta. It positions itself as a hands-on, high-conviction lead investor at pre-seed and seed, which in practice means writing the first institutional check and taking board-level involvement rather than following larger funds into priced rounds.
The transatlantic structure is the distinguishing feature. Israeli companies typically build strong technical teams at home and then have to establish U.S. commercial credibility to reach enterprise buyers. Joule underwrites exactly that transition, with a partner physically in Tel Aviv for sourcing and two in the United States for go-to-market, which is a harder thing to replicate than a thesis.
The track record supports the framing. Exits include BioCatch, Cellwize, Reposify, Pynt, Mirato, Presenso, Simpo and Unomy, all acquired, plus WeWork's public listing. Active positions include Coralogix, Sayari, IronVest, Arnica, Control Monkey, Reeco and Shield IoT, weighted toward security, observability and infrastructure software sold to U.S. enterprises. The fund lineage runs back to 2010 under the former Janvest name, giving the partnership more than a decade of pattern recognition in a niche most U.S. seed funds approach opportunistically.
Investment Thesis
“Invests in early-stage enterprise software, data infrastructure and cybersecurity companies, formerly operating as Janvest Capital Management.”
Sector Focus
Investment Stage
Notable Portfolio Companies
Fund History
- Joule Ventures was formerly Janvest Capital Management, a former name recorded on its SEC adviser registration, and its fund history runs back under that name.
- Janvest Technologies, LP raised $5 million from 58 investors with a first sale in July 2010.
- Janvest Technologies B, LP raised a further $5 million from 47 investors starting in June 2013.
- Janvest Capital Partners C filed a $10 million offering in 2015 with $400,000 sold at the time of filing and no amendment on record.
- Janvest Capital Partners IV closed $33,235,000 from 86 investors against a $100 million offering by July 2020, with a companion IV-A vehicle taking $7.4 million from 26 investors.
- Under the Joule name, Joule Ventures V began raising in August 2023 and had reached $51,631,313 from 82 investors against a $100 million offering by June 2026, alongside a parallel V-A vehicle at $9,040,404 from 30 investors.
- Daniel Frankenstein and Brian Rosenzweig are the two named principals on every vehicle since 2010.
- No limited partners are disclosed.
SEC Fund Filings
- Vehicles filed, last 24 months
- 2
- Latest filing
Joule Ventures filed a Form D for 2 fund vehicles between Sep 30, 2024 and Sep 29, 2026.
| Fund vehicle | Source |
|---|---|
| Joule SPV VI, LP | SEC Form D, filed |
| Joule Ventures V-A, L.P. | SEC Form D, filed |
A Form D is the notice a fund files with the SEC when it raises money in a private offering. Feeder funds, parallel funds and SPVs each file their own, so the count measures filing activity, not the number of flagship funds.
Source: SEC EDGAR Form D filings for pooled investment funds, original filings only (amendments excluded). Our filing data starts Jul 1, 2024. Vehicles are matched to Joule Ventures by fund name and checked against the sponsor address and named principals on each filing; offering amounts are not shown. Each “SEC Form D” link opens an EDGAR full-text search for that vehicle’s exact name, where the filing itself is listed. See every new fund filing on the Form D Radar.
Team (2)
Brian Rosenzweig
Co-Founder & Partner, Joule Ventures
Daniel Frankenstein
Co-Founder & Partner, Joule Ventures
Frequently Asked Questions
What stage does Joule Ventures invest at?
Joule Ventures primarily invests at the Pre-Seed, Seed, Series A, Series B+ stages. This means they focus on companies that are at the earliest idea or prototype phase.
Where is Joule Ventures located?
Joule Ventures is headquartered in New York, NY. Many of their portfolio companies are also based in this region, though they invest across geographies.
What sectors does Joule Ventures focus on?
Joule Ventures focuses on investments in Enterprise, Cybersecurity, SaaS. Their portfolio reflects deep expertise and networks within these sectors.
What is Joule Ventures's typical check size?
Joule Ventures's typical investment check size ranges from $1M to $3M. Actual amounts may vary based on the stage, sector, and specific opportunity.
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