How to Verify and Accept a Loaded SATSCARD

Before accepting a loaded SATSCARD, use compatible software to verify the card, factory certificate, current sealed slot, payment address, balance, and confirmation status. Keep the slot sealed during inspection. Verification reduces protocol and funding uncertainty, but it cannot prove that the physical card was controlled safely before the handoff.

Use a compatible wallet for the strongest check

A plain NFC tap can open a signed, single-use verification link. That is useful for recognizing card state and avoiding a copied static URL. A compatible wallet or the official cktap command-line implementation can perform deeper protocol checks, including validation of the factory certificate and the address derivation inputs.

The open protocol's best practices call for wallet software to verify the certificate before trusting card data. Check the app's current documentation rather than assuming every generic NFC reader performs the same validation.

Acceptance checklist

1. Inspect the physical card

Confirm that the card and six-digit CVC are present and legible. Ask how the sender obtained the card and whether the current slot has ever been unsealed. Keep the card in its RF-blocking sleeve except while using NFC.

A clean-looking card is not a cryptographic check, but unexplained damage, altered markings, or a missing CVC is a reason to stop.

2. Verify card identity and certificate

Use compatible software to connect over NFC. Confirm that the software recognizes a SATSCARD and successfully verifies the factory certificate. A web verification page can check the dynamic signed link, but protocol-aware software can validate more of the card directly.

3. Confirm the active slot is sealed

The current slot must be sealed for the bearer model to make sense. If it has been unsealed, the private key has been revealed and may have been copied. Do not accept an unsealed slot as though physical possession gives exclusive control.

4. Confirm the current address

Match the address derived or displayed by the compatible wallet with the address whose funding you are checking. The printed QR applies to the factory-initialized first slot. If the card has advanced, use the current NFC/app workflow rather than the printed first-slot QR.

5. Check transactions, amount, and confirmations

Verify the unspent balance and transaction history with a Bitcoin data source you trust. Confirm that the amount matches the agreement and apply a confirmation policy appropriate to the value. The NFC chip does not decide whether an on-chain payment is final.

6. Complete physical custody

Receive the card, CVC, and sleeve. Once accepted, protect them as a bearer asset. If exclusivity matters more than continued physical transfer, unseal and sweep promptly into a wallet you control.

What each check establishes

Check	What it helps establish	What it does not establish
Dynamic tap link	The response was freshly signed by the tapped card	Full certificate and address verification by every browser
Factory certificate	The card chains to Coinkite's factory root	Safe custody by every previous holder
Sealed state	The current slot has not reported an unseal transition	No undiscovered implementation or hardware failure
Address derivation	The checked address corresponds to the current card inputs	Sufficient confirmations or future price stability
Blockchain check	Funding and spend status at that moment	That the sender cannot attempt another transaction before confirmation

Decide whether to keep it sealed or sweep

Keeping the slot sealed preserves the ability to pass the card again without an on-chain transfer. Sweeping ends the bearer phase and moves the bitcoin into a wallet whose backup and transaction controls you manage.

For valuable payments, a prompt sweep can reduce exposure to prior custody and physical theft, but it creates the normal responsibility of securing the destination wallet. Prepare the destination before unsealing and follow the unseal-and-sweep guide.

Stop if any critical check fails

Do not accept the card as funded bearer bitcoin if the certificate check fails, the current slot is unsealed, the address does not match, the amount is wrong, or the funding does not meet your confirmation policy. A seller can instead request an ordinary on-chain payment to an address they control.

For the underlying lifecycle, read What is SATSCARD? and How SATSCARD slots work.