Electronic notary
CA 2043533 C · Owner: Pitney Bowes Inc. · Inventors: Durst, Robert T. Jr.; Hunter, Kevin D.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
Method and apparatus for determining that a first unit of data associated with a first party has not been modified since a specified point in time. A method includes the steps of (a) providing the first unit of data and (b) generating a second unit of data from the first unit of data, the second unit of data being expressive of an information content of the first unit of data. The method further includes a step of (c) generating a time indication for specifying a point in time, the time indication being generated with time generation means having a time is settable by a second party other than the first party. Thàt is the time generation means is secured and cannot be altered or changed by …
Read the whole patent
Listed from its CIPO record in Patent Yard's archive of Canadian patents past their term. Its claims, description and drawings are in the CIPO record and on Google Patents, and the Claude kit works from them.
Why it's free to use
- Filed May 30, 1991 and granted June 18, 1996. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended May 30, 2011.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by May 30, 2013.
- We check Canadian rights only. A patent in its family in another country could still be in force: check its family on Google Patents.
Timeline
Timeline From CIPO dates
Sources & verification
Official CIPO records
Everything on this page comes from the CIPO record linked above. Contains information licensed under the Open Government Licence – Canada.