An evidence freshness decision asks whether a dated source still represents the proposition for which it will be used at a stated assessment time. It identifies the claim, source object and version, distinguishes a completed historical fact from a current state or forward-looking capability, records the source period and last verification, names the facts that could have changed, checks for material change or correction, and considers the consequence of relying on a stale result. It returns current for this use, current after bounded confirmation, historical use only, refresh required, freshness unknown or specialist review. It does not replace an explicit tender lookback rule, certificate expiry calculation, evidence-scope comparison, statistical validation or source-conflict decision.
A transport authority asks how the bidder will maintain service during depot communications failures. The fictional Calder Mobility Services Ltd wants to say that its current operating model restored 92 percent of disrupted dispatch sessions within 30 minutes. The source is a signed 2022 service review covering the same company and service. Since then, Calder has replaced the dispatch platform, consolidated four depots into two, changed its night-support supplier and redefined a restored session to exclude delayed vehicle updates. The review remains an authentic record of 2022. Its age alone does not disqualify it, but the changes stop it from proving the proposed current-performance sentence.
Do not assign every source a generic twelve-month life. Age matters through the behavior of the fact. A completion date can remain true for decades, while a staffing roster can be wrong tomorrow. A recent copy of an old table is not fresh evidence, and a long-lived source is not stale merely because its file date looks old. Fix the exact tense and use of the proposal statement, identify the events that could change its truth or relevance, and verify those events at a level proportionate to the consequence. Preserve old evidence as historical evidence when that is all it proves. Where currency is material and cannot be demonstrated, narrow the wording or obtain a new observation.
Direct answer
There is no useful universal age limit for proposal evidence
The right question is not how many months have passed since the file was created. Ask whether the observation still supports the proposition at the time and for the purpose in which the proposal will use it. A 2017 completion certificate can still prove that a named contract was completed in 2017. A support rota approved last week may already be wrong after an employee departure. Both are dated, but only one describes a state that is expected to move.
Fix the evidence object and the assessment instant. Record when the underlying event happened or the measurement period ended, when the source was issued, when its status was last checked and whether a later correction exists. These dates answer different questions. Republishing the same finding changes the publication date, not the age of the finding. A new owner signature can confirm a defined continuity check, but it cannot recreate an observation that was never made.
Freshness is use-specific. The same service report may remain good evidence for the sentence “Calder operated this service in 2022,” require a caveat for “this experience informs our method,” and fail for “our current service achieves the same result.” Store those decisions separately. Do not stamp the report itself current or stale for every possible use.
| Layer | Required facts | Question answered |
|---|---|---|
| Proposition | Exact wording, tense, subject, period and intended use | What must remain supported? |
| Observation | Native source, version, event or measurement period and method | How old is the underlying evidence? |
| Change record | Material change vectors, events checked, sources and gaps | What may have invalidated continuity? |
| Consequence | Effect of error, buyer rule and required reviewer | How strong must currency proof be? |
| Disposition | Permitted wording, prohibited wording, owner and reopen trigger | How may the evidence be used now? |
Claim time
Define the time asserted by the proposal, not only the source date
Underline the temporal work done by the sentence. “Completed,” “has experience,” “currently operates,” “is certified,” “normally achieves,” “can deliver” and “will maintain” make different demands. A completed event is fixed unless the record is corrected or misidentified. Experience can remain part of a team or company history while its practical relevance falls. Current state and normal performance need observations close enough to survive known changes. A future commitment requires capability and authority evidence rather than an old result alone.
Record the function of the sentence as well. A contextual example, participation reference, scored performance claim, risk-control assurance and contractual commitment carry different consequences. The higher the consequence and the faster the subject can change, the stronger the current confirmation should be. This is not a licence to invent a numeric risk score. Name the decisive change and the proof needed to rule it in or out.
Any explicit buyer rule stays authoritative within its scope. If the tender asks for services completed during the previous three years, a factually sound seven-year-old reference may still be outside that requirement. If the tender asks for the present support model, a report from inside a permitted reference window can still be unrepresentative after reorganization. Factual currency and procedural admissibility need separate rows.
Temporal behavior
Classify how the proved fact can age
Historical-event evidence ages differently from state evidence. A signed acceptance can continue to prove that a defined deliverable was accepted on a stated date. It does not show that the same people, product or method remain available. A period measurement, such as response performance for one year, also remains true about that period if its method and population were sound, but it does not automatically describe the next year.
Current-state evidence concerns something that can cease to be true: staff availability, legal status, insurance, product settings, supplier arrangements or policy implementation. Capability evidence sits between state and history. A test proves a capability in the tested version and conditions; later product or environment changes may preserve, improve or break it. A forecast or roadmap is conditional on assumptions and decisions that need their own current status.
Choose change vectors from the proposition, not from a generic checklist. Product behavior may depend on code, configuration, infrastructure, data and interfaces. Service performance may depend on volume, geography, staffing, subcontractors and metric definition. Corporate experience may depend on legal continuity, records, people and assets. If a vector cannot change the conclusion, omit it. If it can, say how it was checked.
| Evidence type | What remains stable | What needs renewed proof |
|---|---|---|
| Completed event | The event, party and result as recorded | Identity corrections, attribution and relevance to a new claim |
| Period measurement | The measured value for its defined population and interval | Current representativeness after definition, population or operating change |
| Present-state record | Only the observed state at the observation time | Continued status at the time claimed |
| Test or assessment | Result for the tested scope, method and version | Effect of later changes on covered behavior |
| Plan or forecast | The approved assumption set at that version | Current approval, dependencies, progress and changed assumptions |
Change evidence
Trace the observation forward through material changes
Start from the native evidence, not the latest paragraph that quotes it. W3C PROV-O distinguishes entities, activities, agents, derivation and revision. For proposal work, that means a copied statistic should retain the service report and measurement period from which it came. A newly approved answer library entry is a new text object, not a new measurement. Its approval can authorize wording while leaving the underlying performance period unchanged.
Build a change trace from the end of the evidence period to the assessment time. Use release records for product changes, organization and supplier records for delivery changes, controlled metric definitions for measurement changes, and accountable source owners for facts not held in a system. Record both positive events and gaps. “No change found” is bounded by the repositories, owners and dates checked; it is not proof that nothing changed anywhere.
The UK Government Data Quality Framework defines timeliness by whether data remains an up-to-date reflection of the period represented and whether the lag is appropriate for the intended use. It also distinguishes data that stays stable from data that moves. That is useful reasoning for proposal evidence, but it does not set a procurement deadline. Apply it to the exact source and disclose what the verification covered.
Decision rule
Set the currency test from change exposure and consequence
Decide what would make the proposition materially wrong. A cosmetic interface change may not affect a throughput claim, while a revised denominator can. A new owner may preserve a controlled process, while an unchanged owner cannot prove that the process still runs. List the few events that matter, the source used for each and the latest observation that would be acceptable for this decision. Avoid labels such as fast-changing unless they point to actual mechanisms.
Raise the evidence requirement when misuse could determine eligibility, misstate a legal or security position, distort price, create a contractual promise or expose a customer. A low-consequence historical illustration can often keep its date and caveat. A current assurance may need a responsible owner, live status source, change review or fresh test. Specialist authority remains necessary where the current conclusion is legal, regulatory, financial, safety or security critical.
Do not average the checks. A recent confirmation of the team does not cure an unreviewed metric change. A product release record does not confirm that field operations stayed the same. Each decisive vector must either be supported, shown immaterial, or left open. If one open vector could defeat the sentence, current use remains unproved.
| State | Meaning | Allowed treatment |
|---|---|---|
| current_for_use | Material continuity is supported for the exact proposition | Use the approved wording and retain the decision |
| current_after_confirmation | A bounded owner or source check closes the only relevant gap | Use only after the recorded confirmation arrives |
| historical_use_only | The source still proves a dated fact but not present state | Keep the date, scope and historical tense |
| refresh_required | A material change occurred or current observation is required | Obtain new evidence before making the current claim |
| freshness_unknown | The change trace or latest state cannot be established | Hold or narrow the affected statement |
| specialist_review_required | Currency depends on a controlled professional judgment | Route the defined question with sources and gaps |
Procurement rules
A procurement reference window is a rule, not a law of evidence decay
Read the live procedure before deciding whether an older reference is allowed. Directive 2014/24/EU Annex XII describes references for works over the past five years and principal deliveries or services over the past three years, while allowing evidence from further back where necessary to ensure adequate competition. German VgV section 46 contains a corresponding three-year rule for relevant supplies and services and permits older examples where the contracting authority says it will consider them. French rules contain their own evidence lists. These are scoped procurement provisions, not a universal shelf life for every report or claim.
The current UK regime takes another form. Section 22 of the Procurement Act allows proportionate conditions concerning legal and financial capacity or technical ability and permits independently verifiable evidence. Cabinet Office guidance notes that the Act does not prescribe one way suppliers must demonstrate the conditions. The exact notice and tender documents therefore matter. Do not import a three-year convention from another regime or an earlier procurement into a current UK answer.
United States FAR 15.305 requires consideration of the currency and relevance of past-performance information, its source, context and trends. FAR 42.1503 provides a defined CPARS-use period for federal source selection. The solicitation still controls the live acquisition. Record each rule beside its jurisdiction, procedure, evidence category and purpose, then send date arithmetic and event validity to the evidence-validity timeline rather than hiding them inside a general freshness label.
Worked case
Keep the 2022 result historical after the operating model changes
The Calder team recovers the signed service review, the metric specification used in 2022 and the current answer draft. The 92 percent result covers disrupted dispatch sessions at four depots from January through December 2022. A session counted as restored when dispatch screens resumed, even if queued vehicle updates were still processing. The proposed sentence uses present tense and suggests that today’s complete service restores within 30 minutes.
The change trace finds a new dispatch platform, two consolidated depots, a different night-support supplier and a revised restoration definition that now includes vehicle-update completion. The legal entity and service purpose remain stable, but the technical path, delivery organization, population and measurement definition changed. None of those differences makes the old report false. Together they make it an unsuitable observation of current performance.
The team rejects the present-tense 92 percent statement. It can use a bounded sentence saying that Calder recorded the 2022 result under the former platform and definition if that history is relevant and disclosure is approved. A current claim needs a fresh measurement under the offered model, with the new denominator and period. A method section may describe current recovery controls from current design and operating records without attaching the old percentage to them.
| Element | 2022 evidence | Current proposition | Finding |
|---|---|---|---|
| Period | January to December 2022 | Normal performance now | Historical observation only |
| Technology | Former dispatch and synchronization platform | Replacement platform in the offered service | Material change requires new evidence |
| Operations | Four depots and former night-support supplier | Two depots and new supplier | Population and delivery path changed |
| Metric | Screens resumed within 30 minutes | Vehicle updates also completed | Definition is not continuous |
| Disposition | 92 percent in 2022 under named conditions | 92 percent current performance | Historical use only; refresh current result |
Disposition
Approve a use, not a timeless green label
The final record names the proposition version, evidence object, represented period, checked change sources, continuity findings, contrary facts, consequence, reviewer, approver and assessment time. It also states the precise wording allowed and the wording that was rejected. If the source is restricted to historical use, keep its date prominent wherever the claim appears. Do not let a reusable library strip away the temporal qualifier.
Set a reopen condition tied to how the fact moves. Product release, supplier change, organizational transfer, revised metric, new operating region, material volume shift, source correction or owner withdrawal can reopen immediately. A calendar checkpoint is useful when relevant changes are not reliably evented, but it is a backstop rather than the reason a source is fresh. Record who will perform the next check and what evidence will close it.
Keep neighbouring decisions separate. Evidence-scope review asks whether entity, service, product, geography and period match. The evidence-validity timeline applies printed expiry, buyer maximum age and required tender events. Statistical review tests the number and method. Evidence hierarchy ranks candidate sources. Answer-library freshness examines a reusable response as a compound object. This decision owns whether one source still represents one proposition at the stated assessment time.
What good looks like
Useful outcomes from how old can RFP evidence be
- Each decision covers one exact proposal proposition, evidence object, version, intended use and assessment time.
- Historical facts, period measurements, present states, current capabilities and forecasts are not given the same lifespan.
- The source date, period represented, publication date, last verification and later corrections remain distinct.
- Material changes to entity, people, process, product, environment, definition or population are checked explicitly.
- A recent re-export or copied paragraph does not reset the age of the underlying observation.
- Explicit buyer lookback and validity rules are preserved as separate binding requirements.
- High-consequence claims receive stronger currency evidence without inventing a universal review interval.
- Older evidence is retained for accurate historical wording instead of being silently upgraded or discarded.
- The accepted wording, permitted use and next change-triggered review are recorded together.
Operating model
How to run the work
- 01
Freeze the intended proposition
Record the exact words, tense, subject, period, answer location and decision for which the source is being considered.
- 02
Identify the underlying observation
Trace the file to the event, measurement, assessment or record it reports, including version and represented period.
- 03
Classify temporal behavior
Decide whether the proposition is an immutable event, interval result, present state, continuing capability or forecast.
- 04
Find material change vectors
Name the people, process, technology, entity, environment, population, definition or external rule that can alter the conclusion.
- 05
Inspect changes and corrections
Use controlled records and responsible owners to test what changed after the evidence period and whether the source was corrected.
- 06
Apply tender-specific rules
Keep any buyer-defined lookback, maximum age, valid-on date or permitted reference period as its own requirement.
- 07
Choose the narrowest sound use
Approve current use, require confirmation, restrict to historical wording, refresh the evidence or leave the issue unresolved.
- 08
Bind wording and review trigger
Link the decision to the final sentence and reopen it after the next material change, correction, source update or required checkpoint.
Evaluation
Questions that change the decision
- What exact fact must the evaluator understand, and is the sentence historical, present-tense or predictive?
- Which event, observation or reporting period produced the evidence rather than merely the current file?
- Can the proved fact change after it occurred, or can only its interpretation and relevance change?
- Which entity, team, process, product, configuration, population, definition and environment determine continuity?
- What material events occurred between the evidence period and the assessment time?
- Has the source owner corrected, withdrawn, superseded or limited the original result?
- Does the tender impose a reference period, maximum document age or current-status rule independent of factual freshness?
- What is the credible consequence if the proposal treats a historical result as current?
- What smaller statement remains accurate if present currency cannot be proved?
- Which future event or elapsed interval should reopen this specific decision?
Failure modes
Where teams lose control
A blanket annual expiry retires stable historical evidence while missing a service change made yesterday.
The date of a newly exported PDF is mistaken for the date of the underlying observation.
A policy approval date is treated as proof that current practice still follows the policy.
An old performance average is described in the present tense after its population or definition changed.
A recent owner confirmation says nothing changed but does not name the components actually checked.
No detected change is presented as proof that a complete change search was performed.
A statutory reference period is converted into a general truth about how long all evidence remains reliable.
A historical record is deleted even though it still proves the event and explains a prior submission.
One freshness score allows serious product drift to disappear behind a recent verification date.
The proposal sentence expands after review without reopening the source-currency decision.
Measurement
Measure the finished job
Measure the completed workflow, including review effort and exceptions. Output volume on its own is not evidence of a better process.
- open freshness decisions by claim, source owner and proposal cutoff
- evidence records with observation period, object version and last verification stored separately
- current-state claims with named change vectors and an accountable verifier
- material changes found after the original evidence period
- recent files rejected because their underlying observations were older
- older sources retained for bounded historical use
- claims narrowed or refreshed before release because currency was not supported
- buyer lookback rules routed to a separate validity check rather than inferred
- freshness decisions reopened by the change event recorded in advance
Questions
Common questions
Is proposal evidence automatically too old after one year?
No. Use the tender’s explicit rule where one exists. Otherwise assess the kind of fact, material changes since the observation and the exact claim. A stable historical event and a current staffing state age differently.
Is newer evidence always better?
No. A recent summary may merely copy an older observation, while an older signed record may be the best source for a historical event. Compare authority, scope, method and represented period.
Can I use an old case study in an RFP?
Possibly. Check the tender’s reference window, preserve the date and actual performer, and do not use past results as current performance without evidence that the material conditions continued.
Does an owner confirmation make old evidence current?
Only for the bounded facts the owner is competent and authorized to confirm. The confirmation should name the change vectors checked and cannot replace a missing measurement or assessment.
How often should proposal evidence be reviewed?
Use material change events first. Add a calendar backstop where events are incomplete, based on how quickly the fact can move and the consequence of stale use. Avoid one cadence for every source.
Should stale evidence be deleted?
No. Preserve it as a historical record where retention and permissions allow. Remove it from current-use suggestions, keep prior decisions traceable and mark the permitted historical wording.
Does reissuing a report reset its freshness?
Not by itself. Record whether the underlying data, represented period, method and conclusion were newly observed, revalidated, corrected or simply republished.
Is freshness the same as certificate or document validity?
No. Validity applies explicit effective dates, expiry, live status, buyer age rules and required tender events. Freshness asks whether the underlying evidence still represents the fact used in the sentence.
Sources
Primary references
- Procurement Act 2023, section 22 on proportionate conditions and verifiable evidence The National Archives
- Cabinet Office guidance on conditions of participation, updated August 2026 Cabinet Office
- Cabinet Office guidance on assessing competitive tenders, updated August 2026 Cabinet Office
- Directive 2014/24/EU, including Articles 58 and 60 and Annex XII EUR-Lex
- German GWB section 122 on suitability criteria and their link to the contract German Federal Ministry of Justice and Consumer Protection
- German VgV section 46 on reference periods and technical ability German Federal Ministry of Justice and Consumer Protection
- French order of 22 March 2019 on information and evidence for public procurement Légifrance
- French Public Procurement Code Article R2143-11 on evidence of capacity Légifrance
- FAR 15.305 on the currency, relevance, source and context of past performance Acquisition.gov
- FAR 42.1503 on performance evaluation records and source-selection use periods Acquisition.gov
- World Bank guidance on evidence for rated procurement criteria World Bank
- UK Government Data Quality Framework on timeliness and fitness for purpose Government Data Quality Hub
- W3C PROV-O recommendation on derivation, revision, activity and responsibility World Wide Web Consortium
- W3C methodology for evaluating accessibility conformance and rerunning evaluations World Wide Web Consortium
- NIST SP 800-53 Revision 5 Update 1, including continuous monitoring National Institute of Standards and Technology
- Companies House guidance on current register searches and filing history Companies House
- Joint Register Portal of the German federal states for company records German state justice administrations
- French public-service guidance on SIREN and SIRET identifiers Direction de l’information légale et administrative
About the author
Tony Kim
Tony writes about applied AI, dependable product engineering and the systems that turn complex response work into controlled delivery.
Ziva
Proposal software for source-grounded RFP, RFI, DDQ and questionnaire response work.
Bid, proposal, presales, security and compliance teams. Start with the workflow, constraints and evidence you already have.