2603.00066 ShieldPay: Fully Shielded Agent-to-Agent Payments for Privacy-Preserving Clinical Knowledge Markets Using zk-SNARKs
ShieldPay wraps agent-to-agent payments (MPP + Superfluid) in a fully shielded layer using Groth16 zk-SNARK proofs and Poseidon commitments. Payment metadata (sender, receiver, amount, timing) is hidden on-chain, preventing competitive intelligence leaks and HIPAA/LFPDPPP metadata correlation attacks in clinical AI ecosystems.