Can one governance law hold across six AI vendors? We ran the same governed prompt through Claude, GPT-5.6, Gemini, Grok, Llama, and watsonx. Five were allowed. One was denied — and the agent halted before the vendor was called. Every run produced a receipt. Every receipt is independently verifiable. Here is what happened.
Enterprise AI governance claims to work across vendors. Most platforms test against one. We tested against six — simultaneously, with the same prompt, under the same policy engine, with no staged failures. The locked runner matrix had four rules: no staged results, the watsonx runner halts immediately on DENY, growth-hack vocabulary stays internal only, and vendor prioritization is founder-timed. We followed all four.
The watsonx run exposed a governance bug in our own evidence path. The policy engine correctly returned APPROVAL_REQUIRED and the agent halted. But the evidence receipt stored the verdict as “allowed” — a binary mapping that defaulted any non-DENY verdict to allowed. Our proudest receipt was lying.
We fixed it. We re-ran R6 through the corrected path with a real correlation ID — the product path, not a workaround. The receipt you can verify above records APPROVAL_REQUIRED truthfully. It took four defects, three re-runs, and one non-receipt to get there.
A vendor claiming a flawless proof run is unremarkable. One that publishes the defect its own test exposed is a governance company. The Proof Run existed to find exactly this. It did its job.
One governance law — the same policy engine, the same evidence schema, the same receipt format — held across six vendors. The allowed runs got receipts. The denied run got a receipt that proved the denial. Every receipt is independently verifiable: click the verify link, the hash recomputes in your browser, not by our server. That is the whole point. PromptKing decides. Your stack enforces. The receipt proves it.