Sourcing control · addendum validation

Supplier addendum validation checklist

Use this checklist after a late evidence addendum is opened. It prevents one late screenshot, supplier message or corrected file from changing a review outcome until authenticity, completeness, relevance and decision impact are tested.

Validation gates

  1. Source check: confirm who sent or found the evidence, when it was received, and where the original file or message is preserved.
  2. Authenticity check: compare file metadata, order number, supplier entity, timestamps, signatures, photos and message headers against the frozen pack.
  3. Completeness check: ask whether the evidence is a full record or only a selected screenshot, partial document or unverified statement.
  4. Relevance check: connect the item to the exact claim, shipment, payment, defect, exception or next-order condition it is supposed to affect.
  5. Impact check: decide whether the item causes no change, a temporary hold, stricter control, relaxed control, delayed decision or reopened review.

Do not accept late evidence when

  • The supplier cannot connect the file to a specific PO, batch, claim or corrective action.
  • The record contradicts inspection, payment, arrival or archive evidence without explaining the conflict.
  • The evidence is only a promise to fix something that still lacks closure proof.
  • The same supplier repeatedly relies on post-freeze documents to avoid review restrictions.
  • Acceptance would weaken a buyer handoff, next-order restriction or dispute record without owner approval.

Checklist table

CheckRequired proofDecision rule
Chain of custodyOriginal email, chat export, inspection file path, payment record or archive link.If the source cannot be preserved, mark provisional or reject.
Supplier identityLegal entity, contact, bank/account reference, factory or trading-company identifier.If identity is unclear, do not relax controls.
Order linkagePO, SKU, shipment, claim, invoice, batch or corrective-action reference.If linkage is weak, treat as background context only.
Conflict reviewComparison against the frozen evidence pack and related archive records.If it conflicts, assign a validation owner before changing status.
Operational impactSpecific affected decision: status, cap, hold, exit, payment, shipment or next-order release.If impact is not explicit, log it but keep the original decision.
Follow-up ownerNamed owner, due date, next evidence expected and escalation trigger.If there is no owner, the addendum is informational only.

Default rule

Late evidence may be valid, but it earns influence only after validation. The addendum can explain a decision; it should not silently replace the evidence timeline.