Shielded Labs, the non-profit organization behind Zcash, has proposed a new upgrade aimed at cryptographically proving the total supply of ZEC coins. This initiative follows the discovery of a bug in the Orchard protocol that could potentially allow the minting of undetectable counterfeit ZEC coins. The privacy features inherent in Zcash's cryptography, while ensuring user anonymity, also prevent verification of whether such a counterfeiting bug has been exploited. Shielded Labs is now working to resolve this issue by engineering a solution that maintains privacy while ensuring supply integrity.