With privacy-preserving and traceability properties, group signature is a cryptosystem with central role in cryptography. And there are lots of application scenarios. A new extension concept of group signature is presented, namely group signature with self-proof capacity. For a legitimate group signature, the real signer can prove that the signature is indeed signed by him/her. While for the other members of the group, they can prove that the signature is not signed by him/her. The former can be used for claiming money reward from the police, while the latter can be used for proving one's innocent in a criminal investigation.

翻译：具有隐私保护和可追溯性的群签名是密码学中扮演核心角色的密码系统，且具有众多应用场景。本文提出一种新的群签名扩展概念——具备自证能力的群签名。对于合法的群签名，真实签名者能够证明该签名确系本人签署；而群内其他成员则可证明该签名并非由本人签署。前者可用于向警方申领悬赏金，后者则可用于在刑事调查中证明自身清白。