seems like this could be vaguely related to proxy re-encryption
Watermarking Public Key Cryptographic Primitives
Watermarking public-key encryption or signatures means modifying the signing/decryption algorithm so that signatures are still verifiable on the same key and ciphertexts decryptable but one can extract a mark from the decryption/signing circuit. The authors suggest new constructions for both, allowing public marking, public mark extraction, and prohibiting mark removal.
seems like this could be vaguely related to proxy re-encryption
Watermarking Public Key Cryptographic Primitives
Watermarking public-key encryption or signatures means modifying the signing/decryption algorithm so that signatures are still verifiable on the same key and ciphertexts decryptable but one can extract a mark from the decryption/signing circuit. The authors suggest new constructions for both, allowing public marking, public mark extraction, and prohibiting mark removal.