Secure element of a transaction system

A secure element of a transaction system comprising multiple transaction partners, the secure element comprising:

• a communication unit configured for receiving at least one certificate from a current transaction partner;
• a certificate verification unit configured to verify the at least one received certificate and to provide a verified data element, wherein the verification unit uses verification data stored in a non-volatile memory of the secure element;
• a transaction unit using the verified data element provided by the certificate verification unit in a current transaction of the transaction system;
• wherein the verification data stored in the non-volatile memory comprise dynamic verification data;
• wherein the dynamic verification data comprise at least two records of previous transactions of the secure element in the transaction system;
• and
• wherein the records in the dynamic verification data stored in the non-volatile memory respectively comprise a certificate reference of at least one previous certificate received and verified in a previous transaction.