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JJ

Joseph Jacks

Verified: Jun 2026 (SMTP Validated)🚀 High-Velocity
San Francisco, CA
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Check Size Range

Flexible Check Size

Preferred Stages
Pre-seed & Seed

Background & Investment Thesis

Founder of OSS Capital. The first and only VC fund dedicated 100% to open-source software companies.

Focus Industries

open-sourcedeveloper-toolsinfrastructure
AI Outreach Insight94% Match Score

Active investor in open-source, developer-tools, infrastructure. Highly responsive to concise pitches with clear traction metrics.

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Key Deal Terms & Quick Facts

Audited venture due diligence summary for Joseph Jacks

Verified Deal Signals
Typical Check Size

Undisclosed ($25k – $250k typical for early angels)

Direct angel check per syndicate / round
Target Stages
Pre-seedSeed
Early-stage entry valuation priority
Founder Pitch Contact

Verified (Protected — Unlock)

Direct mailbox protected against spam
Focus Industries & Categories
open-sourcedeveloper-toolsinfrastructure

Frequently Asked Questions about Joseph Jacks

What is Joseph Jacks's typical angel check size?▼

Joseph Jacks's investment check size typically ranges around Undisclosed ($25k – $250k typical for early angels), participating in early-stage financing rounds alongside leading venture capital funds and angel syndicates.

What stages and sectors does Joseph Jacks invest in?▼

Joseph Jacks primarily backs early-stage startups across Pre-seed, Seed stages, focusing on open-source, developer-tools, infrastructure.

What companies are in Joseph Jacks's angel portfolio?▼

Joseph Jacks actively participates in early-stage technology investments and venture syndicates.

How can startup founders contact or pitch Joseph Jacks?▼

Founders can access verified direct email contact channels, AI-assisted pitch drafting, and syndicate warm intro paths for Joseph Jacks through OpenAngels.