AIBiotech & Life SciencesClimate & EnergyDefense & SpaceEnterprise SoftwareRobotics & AutomationSaaS
SBXi is an early-stage venture capital fund that exclusively backs MIT alumni founders across any sector. It is jointly sponsored by eight firms including Accel, Polaris Partners, General Catalyst, Pillar, Danaher, Underscore VC, Glasswing Ventures, and GETTYLAB, writing $10K-$100K checks on SAFEs and $100K-$1M checks on qualifying priced rounds.
30% of their portfolio is in Consumer. Deal activity decreased year-over-year (1 deal in the last 12 months vs 2 prior). Their most common stage is seed (60% of deals). Average disclosed round size is $6.1M (across 9 rounds with reported amounts).
Portfolio
10
Fund Size
—
Top Stage
Seed
Last 12 Mo
1
Team
Portfolio Breakdown
Stage Distribution
Sector Distribution
Investment Activity
DealsAvg Round Size
Portfolio
10 investments
| Company | Round | Amount | Date |
|---|---|---|---|
| MMagnendo | Series A | $18M | Jul 2026 |
 Unbound | Seed | $4M | May 2025 |
 Unbound | Seed | $4M | May 2025 |
 Surgicure Technologies | Seed | $1.8M | Jan 2025 |
 zeroRISC | Seed | $10M | Jan 2025 |
 Undermind | Pre-Seed | $500K | Sep 2024 |
 Fabri | Seed | $5M | Jan 2024 |
 Nowadays | Unknown | $300K | Jan 2024 |
 M1 Finance | Series A | $11M | Jan 2018 |
 Unbound Security | Seed | — | — |
Top Co-Investors
Y Combinator5 shared
Pioneer Fund4 shared
Wayfinder Ventures3 shared
Massive3 shared
Alpha Square Group3 shared
Unpopular Ventures1 shared
FundersClub1 shared
Lavrock Ventures1 shared
Lockheed Martin Ventures1 shared
Transpose Platform1 shared
Underdog Labs1 shared
Decacorn Capital1 shared
Basis Set Ventures1 shared
Techstars1 shared
Launchpad Capital1 shared
Fontinalis Partners1 shared
private angel investors1 shared
Fundomo1 shared
GG11 shared
BASS Investment1 shared
Last updated: 20 October 2026