💵 QR Code Cash

1. Tamper-Evident Tear-Open QR Code Cash

  • Physical bills are printed by the U.S. Treasury and each corresponds to a unique wallet containing a fixed amount of digital USD tokens.
  • Each note has a tamper-evident seal hiding the private key, and a visible QR code showing the public wallet address.
  • These notes function exactly like physical cash: whoever possesses the paper, possesses the funds.

3. Treasury-Managed Issuance

  • The U.S. Treasury creates a new wallet for every note printed.
  • The treasury creates a unique wallet containing digital USD tokens in advance.
  • The private key is printed and sealed inside the note at the time of issuance.
  • Denominations are fixed and printed directly on the note (e.g., $1, $5, $20).
  • Treasury can actually see exactly how much cash exists

4. Usage Behavior

  • Spending a note does not require opening it.
  • The bearer physically hands the note to the recipient, just like cash.
  • Transferring the funds to a digital wallet does require opening the seal and scanning the private key.
  • Once opened, the note is considered void for further physical transfer, as its private key is exposed.

5. Offline Utility and Finality

  • Notes enable offline peer-to-peer payments, disaster recovery, and unbanked commerce.
  • Value is inherent to the physical item, similar to bearer instruments.
  • Finality is physical until the wallet is drained or the note is opened.

6. Anti-Fraud and Verification

  • Public QR code allows anyone to verify the balance of a note in real time.
  • Scanning the public key reveals:
    • Amount
    • Status (unspent/spent)
    • Wallet history (if transferred digitally)
  • Tamper-evident seals prevent covert access to the private key.

7. Bill Format and Print Specifications

  • Standard U.S. bill size (156mm x 66mm)
  • Public QR (wallet address) printed visibly
  • Private key hidden under tamper-evident tear seal
  • Paper composition similar to cotton-linen cash

8. Treasury Workflow

  • Each note corresponds to a unique wallet
  • Treasury creates a unique wallet at print time and does not store private keys
  • Printed denomination matches wallet balance
  • Enables precise public tracking of all outstanding cash inventory

9. Lifecycle

  • An unopened note can be handed off as cash and retains its bearer-value characteristics.
  • An opened note allows the recipient to digitally redeem the tokens, after which the physical note is void.
  • Anyone can scan the public QR to check its balance at any time.