Data Retention & Deletion

Last updated: 2026-07-14

This page describes how long skink keeps different categories of data, and how you can request earlier deletion.

Principles

Minimize what we store, delete on a defined schedule, and honor deletion requests promptly.

Retention schedule

• Submitted email addresses — stored as a keyed hash and domain by default. Retained 1–90 days per your account's retention setting (7 days by default), then purged automatically. If you opt into keeping a readable copy, it's encrypted at rest and follows the same schedule.
• Verification results — retained on the same schedule as the submitted address.
• Bounce outcome data reported by your ESP — retained 12 months, used to measure and improve verification accuracy over time.
• Bulk upload files and results — retained until your bulk job and its retention window expire; per-email cache entries expire within 24 hours of processing.
• Account and billing records — retained as required for legal, tax, or accounting purposes.

Deletion on request

• You can request deletion of specific addresses or lists at any time — we remove matching records by their hash, including any cached copies.
• Closing your account deletes your data per the schedule above, subject to legal or tax hold requirements.

Automatic purging

A scheduled job removes records once their retention period expires. This runs continuously, independent of any manual deletion request.

Backups

We keep encrypted-at-rest database backups for disaster recovery, retained up to 30 days. Deleting data from the live system (via the retention schedule above or a deletion request) does not retroactively remove it from backups already taken before the deletion — it ages out of backup retention within 30 days on its own. Backups are not used for anything other than restoring service after a failure; they are not queried, analyzed, or accessed as part of normal operation.

Note on hashed storage

We identify records by a keyed hash of the lowercased email address, not a plain hash — a plain hash is efficiently reversible for email addresses given how predictable their format is, so it wouldn't meaningfully protect what you sent us.

Note on opt-in plaintext storage

Storing a readable copy of submitted addresses is off by default. Turning it on is not retroactive — only verifications made after you enable it get a stored copy. Turning it off does not delete or decrypt copies already stored; those are still purged on your normal retention schedule.

Contact

Questions about this page: privacy@skink.dev.