Deposit Screening

Nullmask employs deposit screening to prevent illicit funds from entering the privacy pool.

How It Works

Every deposit to the Nullmask contract must be verified and approved by the guard service before the deposited funds become available as shielded notes.

Screening Criteria

The guard service uses chain analysis tools to evaluate:

• Whether the depositing address is associated with known illicit activity

• Whether the funds originate from sanctioned entities

• Whether the deposit patterns indicate money laundering

Expedited Approval

Deposits originating from well-established centralized exchanges receive expedited approval, since CEXs are responsible for:

• Collecting user KYC data

• Rejecting illicit funds at the point of entry

Rejected Deposits

If a deposit is rejected:

• The deposited funds are refunded to the original depositor

• The gas escrow is paid to the guard

• No note is created in the Merkle tree

User-Initiated Withdrawal

Users can withdraw pending deposits at any time before guard action:

• Call withdrawPendingDeposit() on the contract

• Both deposit amount and gas escrow are refunded