Sean O'Brien
Solo GP · New York, New York
Named as one of two individuals (Chief Financial Officer of Alpha Partners Management LLC, manager of Issuer) on the Form D for Alpha Excel Associates LLC - Series I, a $4.9M venture fund (Mar 2026) (8 vehicles on file: 7 funds, 1 SPV).
Angel Investment Confidence Score
Algorithmic score indicating recent deal velocity, check size reliability, and investment conviction in early-stage startups.
Why Sean O'Brien holds a 89/100 confidence score
- Verified active check-writing activity within the last 12 months
- Target check sizes calibrated between $125K–$400K
- Cross-sector early stage track record
- Named as one of two individuals (Chief Financial Officer of Alpha Partners Management LLC, manager of Issuer) on the Form D for Alpha Excel Associates LLC - Series I, a $4.9M venture fund (Mar 2026) (8 vehicles on file: 7 funds, 1 SPV).
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Check My Startup FitVerified investment track record
Named as one of two individuals (Chief Financial Officer of Alpha Partners Management LLC, manager of Issuer) on the Form D for Alpha Excel Associates LLC - Series I, a $4.9M venture fund (Mar 2026) (8 vehicles on file: 7 funds, 1 SPV).
Source: SEC Form D: Alpha Excel Associates LLC - Series I (Mar 26, 2026) · 7 more sources
- Stages
- Pre-seed, Seed
- Typical check (est.)
- $125K–$400K
- Verified deals
- 7 on file
- Latest activity
- Mar 2026
Is Sean O'Brien a fit for you?
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What sectors does Sean O'Brien back?
Sector focus not yet verifiedVerified investments & deal activity
7 deals trackedRecent startup investments, syndicate rounds, and public co-investments across the US and Europe.
- Mar 2026
Alpha Excel Associates LLC - Series I
Invested through a fund
- Dec 2025
KI Opportunities LLC - Series I
Invested through a fund
- Nov 2025
Silvertech Ventures IV LLC - Series I
Invested through a fund
- Nov 2025
Alpha Sentinel Associates LLC
Invested through a fund
- Nov 2025
Interlock Alpha Associates LLC
Invested through a fund
- Sep 2025
Alpha Pathfinder Associates LLC - Series I
Invested through a fund
- Aug 2025
Alpha Zinc Associates LLC
Invested through a fund
Public Verification Sources
- SEC Form D: Alpha Excel Associates LLC - Series IMar 26, 2026
- SEC Form D: KI Opportunities LLC - Series IDec 9, 2025
- SEC Form D: Alpha Partners Technology Merger SPV LLCDec 3, 2025
- SEC Form D: Silvertech Ventures IV LLC - Series INov 26, 2025
- SEC Form D: Alpha Sentinel Associates LLCNov 26, 2025
- SEC Form D: Interlock Alpha Associates LLCNov 26, 2025
- SEC Form D: Alpha Pathfinder Associates LLC - Series ISep 19, 2025
- SEC Form D: Alpha Zinc Associates LLCAug 28, 2025
Data refreshed from SEC filings and public European announcements Oct 15, 2026. Is this you? Correct or remove this profile.
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