Sigstr

Sigstr was an Indianapolis-based email signature marketing and account-based marketing (ABM) platform that turned employee email signatures into a targeted marketing channel, backed by Battery Ventures and other investors. It was acquired by Terminus in September 2019 and folded into the Terminus platform as its Email Experiences / signature marketing product; the standalone Sigstr brand has since been retired. As of this enrichment pass the sigstr.com domain is a parked WP Engine page (HTTP 404), no api./developer. hosts resolve, and app.sigstr.com CNAMEs to Terminus infrastructure (email2.terminusplatform.com) — the company publishes no public API surface to enrich.

Sigstr is profiled on the APIs.io network. Tagged areas include Company, Email, Email Signature, Marketing, and Account Based Marketing.

📡 Source on GitHub
5.0/100 minimal ▬ flat Agent 0/100 human only Full breakdown ↓
scored 2026-09-08 · rubric v0.20.0
0 APIs
CompanyEmailEmail SignatureMarketingAccount Based MarketingMarTechAcquired

Kin Score

Kin Score Kin Score How this is scored →
scored 2026-09-08 · rubric v0.20.0
Composite quality — 5.0/100 · minimal
Contract Quality 0.0 / 25
Developer Ergonomics 0.0 / 20
Access Clarity 0.0 / 20
Operational Transparency 0.0 / 13
Contract Governance 0.0 / 12
Discoverability 5.0 / 10
Agent readiness — 0/100 · human only
Machine-Readable Contract 0 / 18
Agentic Access Contract 0 / 10
Documented Reversibility 0 / 6
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 0 / 4
Consent & Bot Identity 0 / 3
A2A Agent Card 0 / 8
Dry-Run / Simulate Mode 0 / 4
Delegated User Identity 0 / 6
Protected Resource Metadata 0 / 5
Registration Without a Human 0 / 6
Agentic Commerce Well-Known Document 0 / 5
Create-or-Update Ergonomics could not be measured. We hold no machine-readable contract for this provider to read, so there is nothing to measure a write surface against. Excluded rather than scored zero: never-measured and measured-empty are different facts. Publishing an OpenAPI is what makes this facet — and several others — scorable at all.
Improve this rating by publishing the missing artifacts — every area above can be raised, and the full rubric is at apis.io/rating/. Every facet and dimension name above is a link: it opens that measurement's own page — what it means, the exact checks that feed it, how the whole catalog distributes on it, and the providers at the top of it. This rating is computed from github.com/api-evangelist/sigstr: open an issue to ask a question, or submit a pull request to add artifacts. Submit an artifact on GitHub — free → Manage your own listing — the Influence plan, $499/mo →

Source (apis.yml)

apis.yml Raw ↑ 
aid: sigstr
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://kinlane-images.s3.amazonaws.com/shared/apis-json/icons/sigstr.png
name: Sigstr
description: Sigstr was an Indianapolis-based email signature marketing and account-based marketing (ABM) platform that turned
  employee email signatures into a targeted marketing channel, backed by Battery Ventures and other investors. It was acquired
  by Terminus in September 2019 and folded into the Terminus platform as its Email Experiences / signature marketing product;
  the standalone Sigstr brand has since been retired. As of this enrichment pass the sigstr.com domain is a parked WP Engine
  page (HTTP 404), no api./developer. hosts resolve, and app.sigstr.com CNAMEs to Terminus infrastructure (email2.terminusplatform.com)
  — the company publishes no public API surface to enrich.
url: https://raw.githubusercontent.com/api-evangelist/sigstr/refs/heads/main/apis.yml
x-api-posture: no-product-api
x-api-posture-basis: observed
x-api-posture-note: As of this enrichment pass the sigstr.com domain is a parked WP Engine page (HTTP 404), no api./developer.
  hosts resolve, and app.sigstr.com CNAMEs to Terminus infrastructure (email2.terminusplatform.
x-type: company
x-source: vc-portfolio
x-backed-by:
- battery-ventures
x-tier: stub
x-tier-reason: portfolio-lead
x-status: acquired
x-acquired-by: terminus
x-acquired-date: 2019-09
x-api-surface: none
specificationVersion: '0.23'
created: '2026-07-17'
modified: '2026-07-21'
tags:
- Company
- Email
- Email Signature
- Marketing
- Account Based Marketing
- MarTech
- Acquired
tags_raw:
- Company
- Email
- Email Signature
- Marketing
- Account-Based Marketing
- Martech
- Acquired
apis: []
maintainers:
- FN: Kin Lane
  email: kin@apievangelist.com
- FN: APIs.json
  email: info@apis.io
x-enrichment:
  date: '2026-07-21'
  status: nochange
  artifacts_added: 0
  pass: local-v1

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