Broom Ventures Research
Investment thesis
Broom Ventures is an early-stage venture firm for technology founders. The active official website is https://www.broom.ventures, not broomventures.com, which currently resolves to a domain-sale page. Broom describes its mandate as backing extraordinary pre-seed and seed founders and helping early-stage technology companies reach their full potential. Its philosophy page says the firm believes markets will be reshaped by technology at increasing scale and speed, and that value creation comes from new products, efficiency, and expanded access. The firm's language is unusually operator-heavy for a seed fund: it says it will contribute technical, operational, finance, and other experience with a collaborative co-founder attitude.
The portfolio indicates a broad technology mandate rather than a single-sector specialty. Broom invests across AI software and infrastructure, fintech and financial infrastructure, healthcare technology, defense and aerospace, developer tools, supply-chain technology, education, commerce, climate, and marketplaces. The common pattern is technically enabled companies where a small early-stage team can use software, data, hardware, or infrastructure to enter a large market. Broom's own phrasing around empathetic, mission-oriented founders suggests it cares about founder quality, team dynamics, and culture as much as category selection.
Stage focus
The official homepage states that Broom invests in pre-seed and seed-stage founders. That should be treated as the firm's primary stage focus. Public announcements and portfolio history show some later rounds connected to the firm, including Cofactr's Series A and Tive's Series C, but those appear to be follow-ons or portfolio milestones rather than a signal that Broom is primarily a Series A or growth investor. The SEC Form D for Broom Ventures Fund II lists first sale on July 1, 2023 and identifies the issuer as a pooled investment fund, consistent with an active venture vehicle supporting the firm's early-stage activity.
Check size
Broom does not publish an official firm-wide check-size policy on its website. Third-party investor data for managing partner Jeff Rosen has listed a $500K sweet spot and a $250K to $750K range. Because that source is partner-level and not a formal firm policy, the safest operating assumption is a typical small institutional seed check in the $250K to $750K range, with flexibility for special situations or follow-on participation. The profile should not infer a larger standard check size from later portfolio rounds where Broom was an existing investor or one of many participants.
Lead tendency
Broom appears to be a flexible co-investor more often than a consistent public lead. Recent announcements usually list Broom among multiple investors rather than naming it as the sole lead. Mastra's October 2025 seed round included Broom alongside Mayfield, Tim Tully, Conviction, Databricks, and others. Cofactr's December 2024 Series A was led by Bain Capital Ventures and included participation from Broom as an existing investor. Brick's February 2025 seed round was described as including Honey Island, Broom Ventures, and angel investors. This pattern supports a lead tendency of follows, with room for co-lead or close syndicate participation when the company fits the firm's network.
Recent activity
Broom has visible recent activity across AI, fintech, infrastructure, and defense-adjacent technology. Mastra announced a $13M seed round in October 2025 that included Broom Ventures to build a TypeScript framework for AI agents, workflows, and tools. In February 2025, LatamList reported that Brazilian insurtech Brick raised an $865K seed round from Honey Island, Broom Ventures, and angel investors. In December 2024, Cofactr announced a $17.2M Series A led by Bain Capital Ventures with participation from Broom as an existing investor. Broom's press page also highlights portfolio milestones such as Kapital reaching a $1.3B valuation in September 2025, Anduril raising at a $30.5B valuation in June 2025, and Tive securing a $40M Series C in January 2025.
Portfolio highlights
The official companies page lists a large and diverse portfolio. Defense and aerospace-related examples include Anduril, Epirus, Epsilon3, X-Bow, Phase Four, Muon Space, Astranis, and NuView. AI and developer infrastructure examples include Mastra, Rilla, Standard Metrics, Beam, Lepton AI, Jasper, Toma, and Nylas. Fintech and financial infrastructure examples include Kapital, Seis, KillB, Fidu, OnePay, Extendeal, Pebl, and Spare8. Healthcare and biotech-related companies include Empirical Health, Kento Health, Arkangel AI, and NeuroGeneces. Vertical software and marketplaces include Cofactr, Hammr, Tive, Optimum, Skald, and Velocia. This breadth makes broad technology, enterprise software, developer tools/infrastructure, fintech, healthcare digital, aerospace/defense, climate, and selected consumer/marketplace exposure more accurate than any single tag.
Team
The official team page lists two managing partners. Dan Von Kohorn has founded or co-founded 14 companies and, before Broom, participated in 10 exits totaling more than $900M in enterprise value. His background includes applied research at JP Morgan Investments, software work at a quantitative hedge fund, and venture/investment-management experience involving more than $4.3B. Jeff Rosen is an entrepreneur, COO, and software engineer. He co-founded and served as COO of Rhombus, a data pipeline company acquired by Chainlink, and previously worked on financial exchange, invoice-management, and injury-prevention systems. The SEC filing for Fund II uses a San Francisco address; LinkedIn-style public company profiles have also referenced Boston and Palo Alto locations, so San Francisco is the best source-backed headquarters field from regulatory data while the broader operating footprint appears multi-city.
Decision process
Broom does not publish a formal investment committee process or guaranteed timeline. With two managing partners and a seed-stage orientation, decisions are likely partner-led and relationship-driven. The philosophy page's emphasis on fundamental value, discounted cash flows, probability, payoff multiples, and portfolio construction suggests analytical diligence alongside founder evaluation. For matching purposes, partnership is the best decision-process label, with an estimated one-month timeline rather than a faster fixed commitment.
Founder preferences
Broom's founder preference is explicit in tone even when not expressed as a checklist. The firm wants extraordinary pre-seed and seed founders, especially empathetic and mission-oriented teams building technology companies in large markets. Its team bios and portfolio suggest a preference for technical or deeply operational founders who value hands-on help with engineering, finance, leadership, recruiting, and company-building. Founders seeking purely passive capital or building outside technology-enabled markets are less likely to fit, although the firm does not publish a formal anti-thesis.
Geographic focus
Broom is U.S.-based and source-backed to San Francisco through the SEC Form D. The portfolio is meaningfully international. The companies page and press coverage show exposure to Latin America through Kapital, Fidu, Extendeal, OnePay, Brick, Melian, Mekan, Sytrex, and Arkangel AI, and exposure to India through Advantage Club and Spare8. The practical geography is U.S. first, with selective international investing where founder quality and technology-market fit are strong, particularly in Latin America and parts of Asia.