Return Path

Return Path is an email-deliverability and inbox-intelligence brand that pioneered sender reputation, inbox-placement monitoring, and email fraud protection for marketers and email senders. Founded in 1999 and backed by Sapphire Ventures and Union Square Ventures, Return Path was acquired by Validity in 2019 and now ships as the Validity "Return Path" product line; returnpath.com 301-redirects to validity.com. The platform draws on signals from billions of global mailboxes to measure inbox placement, sender reputation, and deliverability across major mailbox providers. Return Path exposes no publicly documented developer API, SDK, or developer portal today; its capabilities are delivered through the Validity email-success platform.

Return Path is profiled on the APIs.io network. Tagged areas include Company, Martech, Email, Email Deliverability, and Email Marketing.

Return Path’s developer surface includes engineering blog, support, and 14 more developer resources.

🌐 Visit website 📡 Source on GitHub

14.7/100 minimal ▬ flat Agent 4/100 human only Full breakdown ↓
scored 2026-07-27 · rubric v0.5

0 APIs

CompanyMartechEmailEmail DeliverabilityEmail MarketingSender ReputationInbox PlacementDeliverability

Kin Score

Kin Score How this is scored →
scored 2026-07-27 · rubric v0.5

Composite quality — 14.7/100 · minimal

Contract Quality 0.0 / 25

Developer Ergonomics 1.3 / 20

Commercial Clarity 5.3 / 20

Operational Transparency 1.4 / 13

Governance 0.0 / 12

Discoverability 6.8 / 10

Agent readiness — 4/100 · human only

Machine-Readable Contract 0 / 18

Agentic Access Contract 0 / 15

MCP Server 0 / 12

Machine-Readable Auth 0 / 10

Idempotency 0 / 9

Stable Error Semantics 0 / 8

Request/Response Examples 0 / 7

Rate-Limit Signaling 0 / 7

Typed Event Surface 0 / 6

Agent Skills 0 / 5

Well-Known Catalog 4 / 4

Consent & Bot Identity 0 / 3

Improve this rating by publishing the missing artifacts — every area above can be raised, and the full rubric is at apis.io/rating/. This rating is computed from github.com/api-evangelist/return-path: open an issue to ask a question, or submit a pull request to add artifacts. Want it done for you? Prioritized profiling — $2,500 →

Agent Surfaces 1

MCP servers, agent skills, and machine-readable catalogs

WellKnown

WellKnown

Access & Security 8

Authentication, authorization, and security posture

TrustCenter

Compliance

Security

TrustCenter

Compliance

VulnerabilityDisclosure

VulnerabilityDisclosure

Security

Security

DomainSecurity

DomainSecurity

Scroll for all 8

Operate 3

Status, limits, changes, and where to get help

Support

Support

HelpCenter

HelpCenter

Community

Community

Commercial 1

Pricing, plans, and the legal terms of use

PrivacyPolicy

PrivacyPolicy

Company 2

The organization behind the API

Website

Website

Blog

Blog

Other 1

Properties that don't map to a standard resource type

Product

Product

Source (apis.yml)

aid: return-path
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/return-path.png
name: Return Path
description: Return Path is an email-deliverability and inbox-intelligence brand that pioneered sender reputation, inbox-placement
  monitoring, and email fraud protection for marketers and email senders. Founded in 1999 and backed by Sapphire Ventures
  and Union Square Ventures, Return Path was acquired by Validity in 2019 and now ships as the Validity "Return Path" product
  line; returnpath.com 301-redirects to validity.com. The platform draws on signals from billions of global mailboxes to measure
  inbox placement, sender reputation, and deliverability across major mailbox providers. Return Path exposes no publicly documented
  developer API, SDK, or developer portal today; its capabilities are delivered through the Validity email-success platform.
url: https://raw.githubusercontent.com/api-evangelist/return-path/refs/heads/main/apis.yml
x-type: company
x-source: vc-portfolio
x-backed-by:
- sapphire-ventures
- union-square-ventures
x-tier: stub
x-tier-reason: portfolio-lead
specificationVersion: '0.20'
created: '2026-07-17'
modified: '2026-07-20'
tags:
- Company
- Martech
- Email
- Email Deliverability
- Email Marketing
- Sender Reputation
- Inbox Placement
- Deliverability
apis: []
maintainers:
- FN: Kin Lane
  email: kin@apievangelist.com
- FN: APIs.json
  email: info@apis.io
common:
- type: Website
  url: https://www.returnpath.com/
- type: Product
  url: https://www.validity.com/products/returnpath/
- type: Blog
  url: https://www.validity.com/blog
- type: Support
  url: https://knowledge.validity.com/hc/en-us
- type: HelpCenter
  url: https://knowledge.validity.com/hc/en-us
- type: Community
  url: https://mycommunity.validity.com/
- type: PrivacyPolicy
  url: https://www.validity.com/privacy-policy/
- type: TrustCenter
  url: https://trust.validity.com/
- type: Compliance
  url: https://trust.validity.com/
- type: Security
  url: https://trust.validity.com/
- type: TrustCenter
  name: Trust Center (artifact)
  url: security/return-path-trust-center.yml
- type: Compliance
  name: Published compliance program (SOC 2, ISO 27001/27701)
  url: security/return-path-trust-center.yml
- type: VulnerabilityDisclosure
  url: security/return-path-vulnerability-disclosure.yml
- type: Security
  name: Security contact / disclosure
  url: security/return-path-vulnerability-disclosure.yml
- type: DomainSecurity
  url: security/return-path-domain-security.yml
- type: WellKnown
  url: well-known/return-path-well-known.yml
x-enrichment:
  date: '2026-07-20'
  status: enriched
  artifacts_added: 4
  pass: local-v1

Return Path

Kin Score

Security Posture 3

Return Path Domain Security

Return Path Vulnerability Disclosure

Return Path Trust Center

Resources