How would you handle a DMCA takedown notice for image uploads?

WHAT THIS TESTS: This question evaluates whether you can design a system that satisfies legal compliance without sacrificing engineering rigor. Interviewers want to see that you understand non-repudiation, evidence preservation, safe-harbor provisions, and the operational difference between removing public access and destroying data. They also care about your ability to separate content storage from metadata audit trails.

A GOOD ANSWER COVERS: First, immutable upload metadata. You should log a cryptographic hash of the file such as SHA-256, the user ID, a timestamp with timezone, the IP address, user agent, original filename, and a unique upload transaction ID. Second, content-addressable storage so every identical image resolves to a single canonical blob regardless of how many users reference it. This lets you find all public instances of an infringing file via hash lookup rather than slow filename searches. Third, a structured takedown workflow. Upon receiving a valid DMCA notice, the system should suspend the public URL or mark the content as access-restricted, preserve the underlying blob in a legal-hold state, log the takedown action with a case ID, notify the uploading user, and provide a counter-notice mechanism. Fourth, retention policies. Audit logs and metadata must outlive the content itself because a dispute may arrive months after deletion. Fifth, automation guardrails such as hash matching against known infringement databases and rate-limiting repeat offenders.

COMMON WRONG ANSWERS: Proposing to permanently delete the image and all associated records immediately upon receipt of a notice. This destroys evidence and prevents you from proving compliance or defending against a false claim. Suggesting that logging the file path is sufficient without a content hash, which breaks when the file is moved or renamed. Ignoring the counter-notice process entirely, which exposes the platform to liability. Conflating user privacy with evidence destruction, for example arguing that GDPR requires immediate deletion of all upload logs.

LIKELY FOLLOW-UPS: How would you handle a user who deletes their account before the notice arrives? What happens if the same hash is uploaded by ten thousand users simultaneously? How do you distinguish a transformative work from an identical copy when only comparing hashes? Walk me through the database schema that supports this.

ONE CONCRETE EXAMPLE: A user uploads a photograph on January 10. The system writes a row containing the user ID, the SHA-256 hash, the upload timestamp, and the IP address. The image is stored in a content-addressable object store under its hash. On March 5, a rights holder submits a takedown notice including the public URL. An operator queries the URL to retrieve the hash, finds the original upload record, and executes a takedown that replaces the public URL with a 451 unavailable response while moving the blob to a legal-hold bucket. The operator logs the action under case ID 2024-03-05-442, notifies the user, and sets a 14-day timer for a counter-notice. The original upload metadata remains queryable even if the user deletes their account the next day.