GEO supplier assumptions register
What assumptions should a GEO buyer require suppliers to record?
Use a six-part GEO assumptions register to document the statement, evidence, owner, dependencies, impact and review decision behind a supplier proposal or delivery plan.
Published by SALIENS · Published
Hidden assumptions make apparently comparable proposals different
A GEO proposal may assume that approved facts already exist, analytics access will be granted immediately, English and Simplified Chinese reviewers will be available, developers can release recommended changes, priority pages use one content system, or a monitoring sample represents the buyer's real markets. If these conditions are not written down, two similar prices can describe materially different work and risk.
An assumption is not automatically a defect. It is a condition treated as true for planning or decision-making before it has been fully verified. The procurement problem is an assumption that remains implicit, has no owner, or changes the commercial or delivery position without an agreed response. GOV.UK's AQuA Book calls for assumptions to be described, risk assessed, dated, justified, attributed and signed off, with their effect and reliability recorded. GEO buyers can apply the same discipline proportionately.
Create one six-part GEO assumptions register
Ask every shortlisted supplier to complete the same register for material assumptions in its price, scope, timetable, measurement design and delivery method. Retain buyer assumptions as well as supplier assumptions. Give every row a stable identifier so that it can be linked to a risk, dependency, decision, change or acceptance record.
| Register field | What to record | Buyer test |
|---|---|---|
| 1. What is assumed | One precise statement, the affected deliverable or decision, who introduced it and when. Separate the assumption from verified facts and promises. | Could an independent reviewer identify exactly what has not yet been verified? |
| 2. Basis and evidence | Source documents, observations, data period, sample, methodology, reliability, limitations and reason the assumption is currently necessary. | Is there enough evidence to judge whether the assumption is reasonable rather than merely convenient? |
| 3. Owner and authority | Person or role responsible for checking it, buyer and supplier contacts, approval authority, due date and current status. | Is someone accountable for verification and empowered to close or escalate the item? |
| 4. Dependencies and validity | Required access, data, approvals, systems, people, languages and third parties; conditions and period for which the assumption remains valid. | Can the buyer see what must remain true and what other work depends on it? |
| 5. Impact if wrong | Effect on scope, price, timing, quality, security, rights, measurement, English/Chinese delivery and acceptance; related risks and options. | Is the consequence specific enough to compare proposals and plan a proportionate response? |
| 6. Review and decision | Verification method and period, trigger, evidence required, reviewer, decision, approved action and any linked change-control record. | Does failure lead to a defined decision rather than an automatic unbounded claim or price change? |
Keep assumptions separate from facts, risks and dependencies
A fact has been verified for the intended use. An assumption is temporarily treated as true. A risk is an uncertain event or condition that may affect an objective. A dependency is something delivery relies on, and an issue has already occurred. A decision records the authorised response. These records should reference each other, but replacing them all with one vague risk log makes it difficult to see what evidence is still missing.
The Gate 4 Review guidance treats the assumptions register as one linked component of a wider RAID and decision record. For a GEO engagement, an assumption that the buyer's developer can implement schema changes may link to a dependency on release capacity, a risk of delay, and a decision to change the acceptance date. Keep the original assumption visible even after it is verified, rejected or superseded so that a later reviewer can reconstruct the decision.
- Mark every row as proposed, accepted for planning, verified, rejected, expired or superseded.
- Do not convert a supplier statement into a buyer-approved assumption without an identified reviewer.
- Do not use an assumption to hide an exclusion, minimum commitment or unpriced buyer responsibility.
- Link a material failed assumption to the agreed change and decision route instead of rewriting the original record.
Use the register before award and throughout delivery
During proposal comparison, normalise the registers and ask whether one supplier's lower price depends on more buyer inputs, faster approvals, broader access or narrower samples. Before mobilisation, verify high-impact assumptions and place unresolved items into the delivery baseline with owners and dates. During delivery, review assumptions at agreed checkpoints and when a source, market, platform, language, system or buyer priority changes.
Government sourcing guidance describes a specific allowable-assumptions mechanism for defined procurement circumstances, with verification periods and change control. The Mid-Tier Contract guidance says such assumptions should be used carefully, narrowly drafted and not replace information that the buyer should provide. This article does not import that contract mechanism into every GEO purchase. It provides an operational record; buyers should obtain appropriate commercial and legal advice for contractual wording or price adjustment rights.
Test one representative bilingual workflow
Select one priority English and Simplified Chinese page group and trace the proposal from source facts to content, technical implementation, approval, publication and monitoring. Ask the supplier to list every assumption needed to complete that workflow, then supply evidence or an owner and verification date for each one. Include at least one buyer dependency, one technical dependency, one language-review condition and one measurement assumption.
The exercise fails if the supplier cannot distinguish a fact from an assumption, if material impacts are described only as 'to be agreed', if the buyer has no owner for inputs, if the assumption has no expiry or test, or if failure automatically permits an undefined extension or charge. A bounded uncertainty can be managed; an invisible assumption cannot be compared or governed.
Ask SALIENS for a source-linked assumptions review
SALIENS provides GEO audits, AI visibility monitoring, content and technical improvements, and ongoing GEO delivery. A scoped engagement can include proposal-assumption review, English and Simplified Chinese workflow mapping, source and reliability checks, linked risks and dependencies, verification checkpoints and buyer-controlled decision records.
Email info@oxfordintelligence.co.uk with the proposals or delivery plan, intended markets and languages, priority pages and buyer journeys, current evidence, implementation owners, access constraints, procurement timetable and known uncertainties. SALIENS is operated by Oxford Intelligence Limited. An assumptions register does not guarantee crawling, indexation, AI mentions, citations, rankings, traffic or enquiries, and it is not legal or commercial advice.
Sources
- GOV.UK: The AQuA Book — assumptions logs and assurance records (checked 30 October 2026)
- GOV.UK: Gate 4 Review — RAID and assumptions registers (checked 30 October 2026)
- GOV.UK: The Sourcing Playbook — allowable assumptions and change control (checked 30 October 2026)
- GOV.UK: Mid-Tier Contract guidance for buyers — narrowly drafted allowable assumptions (checked 30 October 2026)
- SALIENS: How should a GEO buyer control and approve project changes?
Prepared with AI assistance using the linked sources and SALIENS service information.