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 203 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 4 exemplar · 6 strong
22 agent-ready companies 4 agent-native · 18 agent-ready
Average quality of the book:
Composite thin 37.6
Agent-Readiness agent-aware 23.7

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 128 are tracked as profiles without a published API on the network.

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

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 4 Complete, well-documented, and agent-ready
Strong 6 Solid coverage with minor gaps
Developing 26 Usable, with meaningful gaps to close
Thin 23 Limited public surface area
Emerging 11 Early or largely undocumented
Minimal 5 Almost no public developer surface

Rest of Portfolio

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

ConsensusMulticoin CapitalPolychain Capital

Scroll for all 3

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 169 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
169
of 203 on the roster
Mean Kin Score
22.7
-1.7 vs catalog 24.4
Mean Agent Readiness
11.4
-1.3 vs catalog 12.7
Spread
1.2–87.9
median 14.9 · σ 18.4
How the 169 split by band
Exemplar 4Strong 6Developing 26Thin 23Emerging 50Minimal 60
Facet averages, against the whole catalog
FacetThis cohortCatalogDifferenceScored
Access Clarity 26.7 27.2 -0.5 169
Developer Ergonomics 22.3 23.8 -1.5 169
Contract Quality 18.4 20.4 -2 169
Discoverability 59.4 61.5 -2.1 169
Contract Governance 4.4 6.6 -2.2 169
Operational Transparency 12.1 14.4 -2.3 169

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) 8% 11% -3
MCP server (first-party) 12% 13% -1
Agent Skills 0% 0% 0
OAuth scopes 13% 12% +1
Security 92% 96% -4
Arazzo workflows 3% 2% +1
Governance rules 12% 13% -1

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 87.9
  2. 2 Twilio 77.8
  3. 3 Canvas 73.1
  4. 4 Cloudflare 71.1
  5. 5 Super Payments 64.7
  6. 6 Dwolla 63.7
  7. 7 Etsy 63.1
  8. 8 MongoDB 60.2
  9. 9 Viam 60.2
  10. 10 Microsoft Active Directory 59.8
Top by Agent Readiness
  1. 1 Cloudflare 65.8
  2. 2 MongoDB 59
  3. 3 Stripe 58.3
  4. 4 Dwolla 52.9
  5. 5 Jam 45.5
  6. 6 Yieldmo 45.1
  7. 7 Justworks 42
  8. 8 Neynar 40.6
  9. 9 Blackbird 40.4
  10. 10 Twilio 40.2
This roster declares 203 members; 190 resolve to a provider in the catalog and 169 carry a score (89%). The figures above describe the scored members only.Generated from the catalog build of 22 September 2026, across 27674 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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