Trust & Security

The trust argument is architectural.

Cert doesn't ask you to trust a vendor's cloud with your tax data — it runs inside the Microsoft tenant you already govern. This page is written to be forwarded to IT, security, and legal.

Where your data lives

One design decision does most of the security work: there is no Trojion cloud holding customer data.

Your tenant is the boundary

Cert deploys as a managed Power Platform solution into your existing Microsoft Dataverse environment. Your financial and tax data is stored, processed, and backed up inside your tenant — Trojion has no standing access to it.

You inherit Microsoft's controls

Because the runtime is your environment, your existing Entra ID authentication, conditional access, DLP policies, Purview auditing, encryption at rest, and Dataverse backup and residency settings all apply to Cert automatically.

Data residency follows your Dataverse region

Cert stores nothing outside your Dataverse environment, so your data stays in the Microsoft region your organisation has already chosen — EU, UK, US, or elsewhere.

Signed regulatory releases

OECD rates and thresholds ship as dated, versioned, ECDSA-signed parameter packs. Your environment verifies the signature before applying an update — rates cannot be silently altered.

Every data flow, stated plainly

Three surfaces, three different answers — none of them vague.

The Cert product

Nothing leaves your tenant

Runs entirely in your Microsoft tenant. No customer financial or tax data is transmitted to, stored by, or accessible to Trojion.

Cert IQ (optional add-on)

Request-scoped, opt-in

When enabled, request-scoped context only — for example, the account descriptions being mapped — transits Cert's authenticated Azure gateway to Anthropic's Claude model for the duration of the request. Nothing is retained by Trojion, and commercial API terms prohibit training on your data. Disable Cert IQ and this path does not exist.

This website (cert.tax)

Website only

A static site on Cloudflare Pages. No cookies, no cross-site tracking, no AI. Forms are relayed to our inbox by Web3Forms; analytics, where enabled, is Cloudflare's cookieless measurement.

Integrity of the numbers

Security is also about whether a figure can be silently changed. In Cert, it can't.

Provenance on every figure

Every number traces back through the calculation to the source data that produced it, with the OECD reference cited on each line.

Server-enforced approval workflow

Draft → Reviewed → Approved → Filed is a state machine enforced server-side, not a convention. Sealed filings can only change through visible, attributed amendments.

Evidence Pack

A sealed, auditor-ready record per group, fiscal year, and scenario — inputs, rates, results, and who approved what, when.

Deterministic engine

The calculation engine is deterministic and versioned. The same inputs always produce the same outputs; AI never computes your figures.

Subprocessors

The complete list. Changes are notified to customers in advance.

ProviderScopeApplies to
Microsoft (your tenant)Cert product runtime — Dataverse, Power AppsAll customers (under your own Microsoft agreement, not ours)
Microsoft Azure (Trojion)Cert IQ gateway — authentication, scoping, rate controlOnly with Cert IQ enabled
Anthropic, PBCClaude model inference on request-scoped contextOnly with Cert IQ enabled
Cloudflare, Inc.Marketing website hosting, DNS, cookieless analyticsWebsite visitors only — never product data
Web3FormsWebsite form relay to our inboxWebsite form submissions only

For your procurement file

Everything a purchase decision needs, available on request.

Data Processing Addendum (UK GDPR / EU GDPR) — available on request
Subprocessor list with change notification — the table above, kept current
Security questionnaires (CAIQ, SIG, or your own format) — answered within five business days
Architecture and Cert IQ data-flow walkthrough with your IT and security teams — included in evaluation
Multi-year price lock and licence terms — set out in your proposal
Trojion Consulting Ltd — registered in England & Wales since 2013, company no. 08663271. Registered office: 8 High Street, Heathfield, East Sussex, TN21 8LS.

Put your security team on the demo call.

We'll walk through the architecture and the Cert IQ data flow with IT and legal in the room — that conversation is usually shorter than the questionnaire.