Securing content authenticity

[Guest]

I need to publish documents via ASP.NET and plan on using  pdf API but need to be able to verify that contents have not been changed after publish.

I assume I want to produce PDF's that users can copy, redistribute, read and print but can not edit (or hack) without breaking/removing authenticity certificate/signature from file.

Is this possible and how is it done?

[margueritek]

Use a Certification signature. (Tools->Certificates->Certify). Set permitted actions to "No Changes Allowed"