AmericanFortress, a Wyoming-based team working on post-quantum wallet cryptography, is publishing new research that lets a cross-chain bridge or swap service check, before it pays out, whether the wallet receiving funds on one chain is controlled by the same hidden secret as the wallet that sent them on another. The paper, laid out in the paper, extends a proof system the same authors call ZKPoSP, Zero-Knowledge Proofs of Seed Provenance, from certifying a single derived address to certifying relationships between several addresses at once, including addresses built on entirely different cryptographic curves.