secure vs. e commerce

The only possible way to 'revoke' access to a PDF file is to use Digital Rights Management, such as Adobe's LiveCycle enterprise software. Even then the file is never deleted, it simply cannot be opened with that user's login details.

LiveCycle ES is only sold to large-scale organizations and costs run into the tens of thousands of dollars per server. For individual authors and vanity publishers, sell your work through a third party eBook distributor that handles the DRM, or forget about trying to control revocation and increase your cover price to offset the expected percentage of piracy. Unless you are selling millions of books, or the content is security classified, the costs of running a DRM system vastly outweigh the losses from pirated copies.

nilleg57851248  wrote I want to sell interactive PDF's. and with a time expiration date for use.

what happens when the date runs out;

• the pdf can no longer be downloaded
• any pdf that was already downloaded deletes itself from the local system
• if some person sets their system clock to next year (i.e, past the expiration date)
• if that person sets their system clock back to last year... does it start working again?
• what part of this pdf makes it interactive
• what country [countries] is the pdf allowed to be sold in... more to the point what country is the host server where these pdf files are stored