Open standards for trust signaling.

The Signaling Trust Framework (STF) defines, in plain and testable terms, what constitutes a genuine trust signal across search engines and answer engines. It is the basis of all certification issued by the Authority.

The framework is organized into five core standards, each addressing a distinct dimension of credibility. An organization is certified against the framework as a whole; the standards are not optional modules but complementary requirements.

Each standard is identified by a stable reference (for example, STF-300) and carries a published edition (the current framework edition is STF-2026.2). Certified organizations are always assessed against a specific edition.

The STF Series

The five core standards

Reference	Standard	Requirement summary	Domain
`STF-100`	Entity & Identity Signaling	The organization presents a single, consistent, and verifiable identity across the open web, with no conflicting or fabricated representations.	SEO / AEO
`STF-200`	Structured Data Integrity	Schema and machine-readable markup accurately reflect the underlying content and contain no deceptive or misleading assertions.	SEO
`STF-300`	Citation & Source Provenance	Claims that may be surfaced by answer engines are traceable to attributable, good-faith sources.	AEO
`STF-400`	Local & Geographic Signaling	Location, service area, and physical presence are represented truthfully and consistently.	SEO
`STF-500`	Content Authenticity & Authorship	Authorship is genuine, material relationships are disclosed, and content provenance is not misrepresented.	SEO / AEO

SEO Signaling

Signaling to search engines

Traditional search engines establish an entity’s standing through a web of structured, behavioral, and reputational signals. The framework’s SEO provisions ensure those signals are accurate rather than gamed: that identity is consistent (STF-100), that structured data tells the truth (STF-200), that local representation is honest (STF-400), and that content is genuinely authored (STF-500).

The objective is not visibility for its own sake. It is to ensure that when a search engine reads an organization’s signals, what it reads is true.

AEO Signaling

Signaling to answer engines

Answer engines — the AI systems that summarize, cite, and respond on a user’s behalf — introduce a new class of trust signal. They do not merely rank a page; they decide whether to repeat what it says. That makes provenance paramount.

The framework’s AEO provisions, anchored by STF-300, require that claims likely to be surfaced by answer engines are traceable to attributable, good-faith sources, and that identity and authorship (STF-100, STF-500) remain machine-verifiable. An entity that meets these standards is one an answer engine can cite with confidence.

Editions & versioning

How the framework evolves

Edition	Status	Notes
`STF-2026.2`	Current	Active edition. All new certifications are assessed against this framework.
`STF-2026.1`	Superseded	Remains valid for existing credentials until their next review.
`STF-2025.1`	Archived	Historical reference only.

Detailed clause-level documentation is available through Resources & Publications.

Ready to be measured against the framework?

Certification assesses your organization against the full Signaling Trust Framework and, when met, authorizes the Signaling Compliance Mark.

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