aid: 41st-parameter
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://kinlane-images.s3.amazonaws.com/shared/apis-json/icons/41st-parameter.png
name: 41st Parameter
description: >-
  The 41st Parameter, Inc. was a device-identification and web-fraud-detection
  company founded in 2004 and headquartered in Silicon Valley, with offices in
  Arizona, the UK, and Tokyo. Its device intelligence technology reduced fraud
  detection false positives for use cases such as new-account fraud, card-not-present
  (CNP) online transaction risk scoring, and account-takeover protection. Experian
  acquired the company in October 2013 and folded its device-recognition technology
  into Experian's global web-fraud and risk-based identity-authentication portfolio
  (FraudNet). 41st Parameter no longer operates as a standalone entity and publishes
  no independent developer portal, API, or documentation. This profile was surfaced
  as a portfolio company of kleiner-perkins and retained in the API Evangelist
  network as a historical record.
url: https://raw.githubusercontent.com/api-evangelist/41st-parameter/refs/heads/main/apis.yml
x-type: company
x-source: vc-portfolio
x-backed-by:
- kleiner-perkins
x-tier: stub
x-tier-reason: acquired-defunct
x-status: acquired
x-acquired-by: experian
x-acquired-date: '2013-10-01'
x-founded: '2004'
specificationVersion: '0.20'
created: '2026-07-17'
modified: '2026-07-17'
tags:
- Company
- Enterprise
- Fraud Detection
- Device Intelligence
- Web Fraud
- Identity Verification
- Account Takeover
- Acquired
apis: []
maintainers:
- FN: Kin Lane
  email: kin@apievangelist.com
- FN: APIs.json
  email: info@apis.io
x-enrichment:
  date: '2026-07-19'
  status: backfilled
  pass: local-v1
  note: backfilled from .gitignore signal + verified work evidence