A method is provided for an escrow cryptosystem that is overhead-free, does not require a cryptographic tamper-proof hardware implementation (i.e., can be done in software), is publicly verifiable, and cannot be used subliminally to enable a shadow public key system. A shadow public key system is an...http://www.google.com.au/patents/US6202150?utm_source=gb-gplus-sharePatent US6202150 - Auto-escrowable and auto-certifiable cryptosystems
