US 12,229,320 B1
PDF tracking for local editing and digital signing for applications
Reed Wentworth Owens, Damascus, MD (US)
Assigned to UXSTORM, LLC, Damascus, MD (US)
Filed by UXSTORM, LLC, Damascus, MD (US)
Filed on Nov. 11, 2022, as Appl. No. 17/985,793.
Int. Cl. G06F 21/64 (2013.01); G06F 21/60 (2013.01)
CPC G06F 21/64 (2013.01) [G06F 21/602 (2013.01); G06F 2221/2107 (2013.01)] 8 Claims
OG exemplary drawing
 
1. An application server system for verifying the provenance of a candidate Portable Document File comprising:
a processor operably connected to a network and non-transitory computer instruction storage media storing computer instructions configured to cause the processor to:
receive over a network a request for a Portable Document File from a client user computer;
determine whether the request corresponds to a previously generated Portable Document file and transmit the previously generated Portable Document File to the client user computer if so; otherwise:
generate an integrity key unique to the Portable Document File and the request;
encode the integrity key in the Portable Document File in an annotation;
encode the annotation to be hidden;
store the Portable Document File in a local data store and set a processed flag associated with the integrity key to false; and
transmit the Portable Document File to the client user computer;
after transmitting the Portable Document File or the previously generated Portable Document File to the client user computer:
receive over the network from the client user computer a candidate Portable Document File;
search the candidate Portable Document File for a candidate hidden annotation;
if the candidate hidden annotation is found, extract a candidate key from the candidate hidden annotation and compare it to the integrity key and pass the candidate Portable Document File for further processing and set the processed flag associated with the integrity key to true if the integrity key and candidate key match;
if the hidden annotation is not found or the integrity key and candidate key do not match, transmit a rejection message over the network to the client user computer.