Keeping every authentication report forever is not a retention policy. Raw aggregate data, message-specific failure reports and investigation notes serve different purposes and carry different risks. A useful retention plan explains why each class is kept, how long it remains useful and what happens when that period ends.
DMARC's reporting specifications describe report content, privacy and security considerations. They do not establish a universal legal retention period for every organization. The workflow below is an operational design to review with the people responsible for privacy, security and applicable legal obligations.
Inventory the actual record classes
References: RFC 9990 §7.1, RFC 9990 §7.2, RFC 9991 §2, RFC 9991 §7.1.
Separate raw aggregate reports, parsed records, summarized metrics, failure reports, controlled-message samples and incident conclusions. Identify who owns each store and every downstream copy: mailbox, parser queue, analytics system, ticket, analyst export and backup.
Standard aggregate reports exclude individual message content and identifying end-user information under RFC 9990 §7.2, but traffic metadata can still expose operational patterns under RFC 9990 §7.1. Do not treat an aggregate store as exempt from access and retention review. Aggregate reports include infrastructure and traffic information that can still require appropriate handling. Failure reports deserve particular attention because they may contain message headers, bodies and identifiers. Classify based on actual and possible content rather than the file extension or dashboard label.
Set a purpose and clock for each class
State why the record is retained: ingestion troubleshooting, seasonal comparison, a specific investigation or an applicable obligation. Define when the retention clock begins, such as report receipt or incident closure, and who owns exceptions. Avoid ambiguous instructions such as keep for a while after use.
Choose durations based on documented needs and obligations, not a number copied from a generic security checklist. A long seasonal comparison might be served by appropriately minimized metrics while raw message content is kept for a much shorter diagnostic need. Verify that the summary retains the context needed to interpret coverage and configuration changes.
Work through a retention design
Illustrative design: raw aggregate reports support parser troubleshooting; derived counts support longer trend analysis; message-specific reports support a time-bounded investigation; a redacted incident conclusion preserves the cause and corrective action. Each class has its own approved duration, start event, owner and deletion method.
The example intentionally does not assign universal day counts. An organization's obligations and systems determine them. If an incident requires an exception, record the reason, scope, approver and review date. Preserve relevant evidence under a valid hold rather than allowing normal deletion to destroy it, while avoiding an unlimited hold on unrelated data.
Calculate one synthetic register row
The following row uses arbitrary hypothetical approvals solely to demonstrate retention mechanics. Its seven-day duration is not a recommendation, legal minimum or claim about any organization's current policy. Every timestamp is UTC.
- Register field: Record class and identifier; Hypothetical value: Raw failure-report fixture RET-TEST-01 containing no real message data
- Register field: System and accountable owner; Hypothetical value: Isolated test report store; report-operations owner
- Register field: Purpose; Hypothetical value: Verify the test parser's handling of the harmless fixture
- Register field: Clock start; Hypothetical value: Receipt at 2026-11-01T10:00:00Z
- Register field: Hypothetical approved duration; Hypothetical value: Seven elapsed 24-hour days from receipt
- Register field: Calculated expiry; Hypothetical value: 2026-11-08T10:00:00Z
- Register field: Disposal targets; Hypothetical value: Active fixture object, parsed message-content copy and temporary plaintext copy
- Register field: Exception decision; Hypothetical value: No hold in the base case; a separately approved hold can suspend disposal of this specific record
- Register field: Backup treatment; Hypothetical value: A test backup follows its documented separate expiry; restored records are checked against original expiry and hold state before ordinary access
For the unheld case, the proposed check at 2026-11-08T09:59:59Z should find the fixture retained; the check at expiry should find it eligible for disposal. Run the cleanup and verify the listed active disposal targets are removed, retaining only an approved minimal disposal event. Expiry eligibility and successful deletion are separate facts: an unsuccessful job leaves an overdue record and requires an owner, not a false deletion entry.
For a held case, assume a scoped test hold is approved at 2026-11-07T12:00:00Z. The expiry check should preserve the held record in controlled storage and identify the hold reference. If the hold is released at 2026-11-10T10:00:00Z, the original expiry has already passed; the record should enter the approved disposal process rather than automatically receiving a fresh seven days.
For a restore test, restore a backup containing RET-TEST-01 on 2026-11-09T10:00:00Z. With no active hold, prevent the expired record from returning to ordinary access and apply the approved disposal process. With an active scoped hold, preserve it only in the controlled hold workflow. These are proposed outcomes, not completed system tests; the offline timestamp calculation verifies arithmetic only.
Make expiry work across copies
Test whether deletion from the main application also removes exports, cached previews, temporary parser files and ticket attachments. Backups may follow a different expiry schedule; document it and control access instead of claiming immediate erasure where it is not technically true.
Plan how restored backups are handled so expired material is not silently reintroduced into routine use. Determine whether contractual processors can apply the approved schedule and provide meaningful evidence. A retention statement is incomplete if the organization cannot identify which system performs the deletion.
Preserve useful evidence without excess content
References: RFC 9991 §7.
Before deleting a diagnostic report, determine whether an approved minimized record should preserve the relevant identity, time, failure condition, corrective action and verification result. Remove unnecessary message content, recipients and secrets from the retained narrative. Check the extract rather than assuming an automated redaction is complete.
Use controlled access while records are retained. A short lifetime does not make an unprotected store acceptable, and encryption does not eliminate the need to delete data that is no longer needed.
Review the policy as systems change
Revisit the schedule after adding a reporting processor, changing export integrations or discovering that records contain more sensitive content than expected. Keep a test record of expiry behavior and exceptions, including what cannot yet be deleted as intended.
The final deliverable is a small retention register with record class, purpose, system, owner, clock, approved duration, exception process and verified disposal behavior. It should describe what the organization actually does, with unresolved gaps assigned for correction.
Keep the illustration within its evidence
The local UTC calculation confirms seven elapsed days from 2026-11-01T10:00:00Z reach 2026-11-08T10:00:00Z. Release and restore timestamps are later than that original expiry; they do not restart it. Only arithmetic was executed. No deletion, legal hold, backup restore or system disposal test was performed.