Venture Capital

Union Square Ventures

Union Square Ventures (USV) is a thesis-driven, early-stage venture capital firm founded in 2003 by Fred Wilson and Brad Burnham and headquartered at 817 Broadway in New York City. USV invests at the edge of large markets being transformed by technological and societal pressures, historically backing large networks of engaged users that are differentiated through user experience and defensible through network effects, and more recently companies that broaden access to knowledge, capital, and well-being. The firm invests primarily at Seed and Series A across three strategies — a Core fund, a Climate fund, and an Opportunity (later-stage) fund — with check sizes typically ranging from roughly $1M at seed to the low-to-mid single-digit millions at Series A. USV runs a small, collegial partnership and focuses on social media, marketplaces, developer tools, learning/education, health, fintech, web3/decentralized protocols, energy, and climate. It reports roughly $1.9B in assets under management across 14 funds. Notable investments include Twitter, Etsy, Coinbase, Stripe, Cloudflare, MongoDB, Twilio, Duolingo, Kickstarter, Stack Overflow, SoundCloud, and Carta.

206 portfolio companies 204 publish APIs here 13 properties
Venture CapitalSeedSeries AFintechMarketplaceDeveloper ToolsWeb3ClimateNew York
Portfolio Strength across 75 profiled portfolio companies on the network
10 top-rated API companies 5 exemplar · 5 strong
22 agent-ready companies 6 agent-native · 16 agent-ready
Average quality of the book:
Composite thin 37.2
Agent-Readiness agent-aware 23.4

Firms are ranked by cumulative portfolio strength — how many highly-rated API companies they've backed, weighted by tier across composite quality and agent-readiness. The averages below are a secondary read on the typical company in the book.

Union Square Ventures has 206 portfolio companies tracked on the APIs.io network, of which 75 (36%) publish APIs indexed here. The remaining 129 are tracked as profiles without a published API on the network.

Its highest-rated API providers on the network are Twilio, MongoDB, Stripe, Cloudflare, Canvas.

Portfolio on the Network

Portfolio companies that publish APIs indexed on APIs.io, grouped by their API Evangelist rating. Exemplar and Strong are expanded by default.

Exemplar 5 Complete, well-documented, and agent-ready
Strong 5 Solid coverage with minor gaps
Developing 23 Usable, with meaningful gaps to close
Thin 25 Limited public surface area
Emerging 12 Early or largely undocumented
Minimal 5 Almost no public developer surface

Rest of Portfolio

2 further portfolio companies that don’t yet have a provider page on the network.

Multicoin CapitalPolychain Capital

Scroll for all 2

Properties

Portfolio

Where the firm publishes its investments

Team

Partners and investing staff

Content

Blog, podcast, newsletter, and research

Firm

The firm itself

Cohort brief

Auto-generated

The 172 portfolio companies with APIs in the catalog, backed by Union Square Ventures, scored on the Kin Score. Every figure below is computed from the catalog — nothing here is written.

Providers
172
of 204 on the roster
Mean Kin Score
21.4
-1.5 vs catalog 22.9
Mean Agent Readiness
11.2
-0.8 vs catalog 12
Spread
0–82.1
median 13.6 · σ 18.2
How the 172 split by band
Exemplar 4Strong 6Developing 23Thin 25Emerging 49Minimal 65
Facet averages, against the whole catalog
FacetThis cohortCatalogDifferenceScored
Access Clarity 25.9 26.4 -0.5 172
Developer Ergonomics 21.9 23.1 -1.2 172
Contract Quality 16.1 17.6 -1.5 172
Discoverability 56.6 58.2 -1.6 172
Operational Transparency 11.6 13.6 -2 172
Contract Governance 4.2 6.3 -2.1 172

A facet is averaged over the members that carry it, not over the whole cohort — the “Scored” column is that count. Averaging an absent facet as zero would score our own coverage gaps as the providers’ posture.

What this cohort publishes
ArtifactThis cohortCatalogDifference
MCP server (any) 15% 15% 0
MCP server (first-party) 12% 12% 0
Agent Skills 0% 0% 0
OAuth scopes 13% 11% +2
Security 98% 98% 0
Arazzo workflows 3% 2% +1
Governance rules 13% 13% 0

mcp_pct counts any mcp/ artifact including ones API Evangelist derived from the provider OpenAPI; mcp_first_party_pct counts only servers the provider publishes. Prefer the latter.

Top by Kin Score
  1. 1 Stripe 82.1
  2. 2 Twilio 74.3
  3. 3 Cloudflare 71.9
  4. 4 Canvas 68.7
  5. 5 MongoDB 62.9
  6. 6 Microsoft Active Directory 62
  7. 7 Dwolla 61.6
  8. 8 Super Payments 61.6
  9. 9 Viam 60.7
  10. 10 Etsy 58.7
Top by Agent Readiness
  1. 1 Cloudflare 65.5
  2. 2 MongoDB 58.6
  3. 3 Stripe 58.3
  4. 4 Dwolla 52.9
  5. 5 Jam 45.5
  6. 6 Yieldmo 43.3
  7. 7 Justworks 42
  8. 8 Blackbird 40.4
  9. 9 Twilio 40.2
  10. 10 Neynar 40.1
This roster declares 204 members; 190 resolve to a provider in the catalog and 172 carry a score (91%). The figures above describe the scored members only.
Coverage caveat. 148 of 172 scored members had under half their catalog-attributable points satisfied at all (catalog_earned / catalog_max < 0.5). They are INCLUDED in the mean above. A large share here means the cohort mean is partly a measurement of how far our enrichment reached, not only of how these providers publish.Generated from the catalog build of 3 October 2026, across 28834 providers, using the same computation served by the APIs.io cohort API. Briefs are published for rosters of 5 or more scored providers; below that a distribution is not meaningful.

Source (apis.yml)

apis.yml Raw ↑
aid: union-square-ventures
name: Union Square Ventures
description: >-
  Union Square Ventures (USV) is a thesis-driven, early-stage venture capital
  firm founded in 2003 by Fred Wilson and Brad Burnham and headquartered at 817
  Broadway in New York City. USV invests at the edge of large markets being
  transformed by technological and societal pressures, historically backing
  large networks of engaged users that are differentiated through user
  experience and defensible through network effects, and more recently companies
  that broaden access to knowledge, capital, and well-being. The firm invests
  primarily at Seed and Series A across three strategies — a Core fund, a
  Climate fund, and an Opportunity (later-stage) fund — with check sizes
  typically ranging from roughly $1M at seed to the low-to-mid single-digit
  millions at Series A. USV runs a small, collegial partnership and focuses on
  social media, marketplaces, developer tools, learning/education, health,
  fintech, web3/decentralized protocols, energy, and climate. It reports roughly
  $1.9B in assets under management across 14 funds. Notable investments include
  Twitter, Etsy, Coinbase, Stripe, Cloudflare, MongoDB, Twilio, Duolingo,
  Kickstarter, Stack Overflow, SoundCloud, and Carta.
x-type: venture-capital
x-category: Venture Capital
deliveryModel:
  model: unknown
  open_source: false
  commercial: false
  callable_host: false
  label: Delivery model not determined — needs a product licence on record
  confidence: low
  source:
  - none
  generated: '2026-08-28'
  method: derived
accessModel:
  pricing: unknown
  onboarding: unknown
  trial: false
  try_now: false
  public: false
  label: Unknown
  confidence: low
  source: []
  generated: '2026-07-22'
  method: derived
image: https://www.usv.com/favicon.ico
tags:
  - Venture Capital
  - Seed
  - Series A
  - Fintech
  - Marketplace
  - Developer Tools
  - Web3
  - Climate
  - New York
tags_raw:
  - Venture Capital
  - Seed
  - Series A
  - Fintech
  - Marketplaces
  - Developer Tools
  - Web3
  - Climate
  - New York
created: '2026-07-17'
modified: '2026-07-17'
specificationVersion: '0.23'
apis: []
common:
  - type: Website
    url: https://www.usv.com/
  - type: Portfolio
    url: https://www.usv.com/companies
  - type: Portfolio
    url: portfolio/union-square-ventures-portfolio.yml
  - type: Team
    url: https://www.usv.com/people/
  - type: Team
    url: team/union-square-ventures-team.yml
  - type: InvestmentThesis
    url: https://www.usv.com/about/
  - type: InvestmentThesis
    url: https://www.usv.com/idea/usv-investment-thesis/
  - type: Blog
    url: https://www.usv.com/writing/
  - type: Jobs
    url: https://jobs.usv.com/
  - type: Contact
    url: mailto:info@usv.com
  - type: Crunchbase
    url: https://www.crunchbase.com/organization/union-square-ventures
  - type: LinkedIn
    url: https://www.linkedin.com/company/union-square-ventures
  - type: Twitter
    url: https://twitter.com/usv
  - type: Features
    data:
      - 'Stage: Seed and Series A (early-stage), plus later-stage via the Opportunity fund'
      - 'Typical check: ~$1M at seed, low-to-mid single-digit millions at Series A'
      - 'Sectors: social media, marketplaces, developer tools, learning/education, health, fintech, web3/decentralized protocols, energy, climate'
      - 'Geography: United States (NYC-based), with global investments including Europe'
      - 'AUM: ~$1.9B across 14 funds (self-reported)'
      - 'Strategies: Core fund, Climate fund, Opportunity (later-stage) fund'
      - 'Founded: 2003'
      - 'Founders: Fred Wilson, Brad Burnham'
      - 'HQ: 817 Broadway, 14th Floor, New York, NY 10003'
    sources:
      - https://www.usv.com/about/
      - https://www.usv.com/idea/usv-investment-thesis/
      - https://www.crunchbase.com/organization/union-square-ventures
    updated: '2026-07-17'
maintainers:
  - FN: Kin Lane
    email: kin@apievangelist.com
    url: https://apievangelist.com
  - FN: APIs.json
    url: http://apisjson.org
  - FN: Union Square Ventures
    url: https://www.usv.com/

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