Gregory Mazlin
Solo GP · New York, New York
Named as the only individual (The Managing Member of the General Partner) on the Form D for Sideline Group Fund I, L.P., a $139.4M venture fund (Mar 2026) (3 vehicles on file: 1 fund, 2 SPVs).
Angel Investment Confidence Score
Algorithmic score indicating recent deal velocity, check size reliability, and investment conviction in early-stage startups.
Why Gregory Mazlin holds a 80/100 confidence score
- Verified active check-writing activity within the last 12 months
- Target check sizes calibrated between $1.4M–$4.2M
- Cross-sector early stage track record
- Named as the only individual (The Managing Member of the General Partner) on the Form D for Sideline Group Fund I, L.P., a $139.4M venture fund (Mar 2026) (3 vehicles on file: 1 fund, 2 SPVs).
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Check My Startup FitVerified investment track record
Named as the only individual (The Managing Member of the General Partner) on the Form D for Sideline Group Fund I, L.P., a $139.4M venture fund (Mar 2026) (3 vehicles on file: 1 fund, 2 SPVs).
Source: SEC Form D: Sideline Group Fund I, L.P. (Mar 24, 2026) · 2 more sources
- Stages
- Seed, Series A
- Typical check (est.)
- $1.4M–$4.2M
- Verified deals
- 1 on file
- Latest activity
- Mar 2026
Is Gregory Mazlin a fit for you?
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What sectors does Gregory Mazlin back?
Sector focus not yet verifiedVerified investments & deal activity
1 deal trackedRecent startup investments, syndicate rounds, and public co-investments across the US and Europe.
- Dec 2024
Sideline Group Fund I, L.P.
Invested through a fund
Public Verification Sources
- SEC Form D: Sideline Group Fund I, L.P.Mar 24, 2026
- SEC Form D: Sideline Group Urban Golf SPV, L.P.Jun 10, 2025
- SEC Form D: Sideline Group Bandit SPV, L.P.Dec 17, 2024
Data refreshed from SEC filings and public European announcements Oct 15, 2026. Is this you? Correct or remove this profile.
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