Verifying the authenticity of printed documents

The method of creating at a particular location a receipt indicative of a prior transaction between a purchaser and a seller of service, said receipt having self proving capability, and said particular location being remote from said seller, said method comprising the steps of:

• communicating to said seller data which is unique to the material upon which the receipt is to be generated;
• said seller verifying satisfaction with said unique data;
• and
• said seller communicating to said particular location data for associating with said receipt material, said last-mentioned data operable at said particular location for creating said receipt;
• said seller transmitted data including at least one machine decodable portion, the key to said decodable portion contained within at least a portion of data which is unique to said receipt material.

A system for establishing the validity of a display, said system comprising:

• a device for creating said display on media containing preestablished data which is unique to said media;
• and
• communicating at least a portion of said preestablished data to a location independent from said creation device, said independent location operable to create on said media in conjunction with said creation device a security indicia, as part of a human readable display, said security indicia created in part by information contained in said preestablished media data and whereby said security indicia is validatible at a subsequent time partially under control of data contained in said preestablished media data;
• wherein said media is paper, and wherein said device is a nonsecure printer;
• wherein said paper is divided into sections, each section adapted for printing thereon information pertaining to a different display, each such display having associated therewith a security indicia.

A method for verifying the authenticity of a document, wherein said document was previously created on a stock, comprising:

• decoding a first indicia, that was pre-printed on said stock before creation of said document, to determine a unique code, wherein said unique code includes an encryption key;
• decoding a second indicia that is included in said document to determine encrypted authentication information;
• decrypting said encrypted authentication information in accordance with said encryption key;
• and
• selectively permitting a consumer to complete a commercial transaction in accordance with said authentication information.

A system for verifying the authenticity of a document, wherein said document was previously created on a stock, comprising:

• means for decoding a first indicia, that was pre-printed on said stock before creation of said document, to determine a unique code, wherein said unique code includes an encryption key;
• means for decoding a second indicia that is included in said document to determine encrypted authentication information;
• means for decrypting said encrypted authentication information in accordance with said encryption key;
• and
• means for presenting said authentication information to a gatekeeper to allow said gatekeeper to selectively permit completion of a commercial transaction by a consumer.