The legal scenarios where AI evidence matters
IP dispute: someone alleges your product is based on AI-derived work from a leaked training set. Defensive evidence: receipts showing which AI assisted which code, when, supervised by whom. Contract dispute: a vendor claims you owe them AI-related fees you didn't actually incur. Defensive evidence: receipts showing the actual usage, signed and timestamped. Employee dispute: a former engineer claims work product was theirs. Defensive evidence: per-engineer attribution on every receipt.
Standards for digital evidence admissibility
Most jurisdictions require: (1) the evidence was created at the time of the event (not reconstructed). (2) chain of custody is preserved. (3) the format is verifiable. Receipts satisfy all three: issuance is at the time of the AI call, signature provides chain of custody, JCS-canonical JSON + Ed25519 are standard verifiable formats. Your IT expert can verify any receipt offline with openssl + node.
Privilege considerations
Receipts are factual records of AI usage. They're not legal advice. They can be discoverable in litigation — which can be a problem (receipts showing problematic AI usage) or a benefit (receipts proving compliant usage). Talk to your in-house team about your discovery posture; the same logic applies to any audit log.
EU AI Act + GDPR overlap
For EU-touching businesses: AI Act §50 transparency + GDPR Article 22 human-supervision exemption both require evidence of human involvement in AI decisions. Receipts capture the reviewer_human_id + the timestamp of review. This becomes both the AI Act §50 evidence and the GDPR Article 22(2)(a) evidence — one record, two regulatory frames satisfied.
M&A due diligence — receipts as asset disclosure
In M&A: the buyer's diligence increasingly asks "what AI was used to build the target's product and what data did it touch?". Without receipts: vague answer. With: the AI bill of materials and the data-flow audit are queryable from the receipt feed. The target presents better diligence; the buyer accepts a smaller indemnity. The deal closes faster and cleaner.
Counsel's 5-minute gut check
For your client's AI usage: is there a credible scenario in the next 18 months where they'd need to defend their AI activity in litigation, regulatory inquiry, or M&A diligence? If yes (most clients with non-trivial AI usage), the receipt audit trail is rational risk management. If no (pure exploration, no production use), defer.