I have a PDF file that I would like to add Long Term Validation (LTV) to, how can this be achieved?
The functionality can be achieved using the low level SDF API to manipulate the document objects directly in order to add the LTV information. LTV information for PDF files should be written into the DSS dictionary which itself should be present in the Catalog object. It’s the data that is in this dictionary which should be read by any application performing validation on the PDF file. You can read further information about the DSS in the PDF standard: http://xodo.com/view/#/c0c11968-ee14-478e-9b09-6dc5635c0915 section 220.127.116.11 “Document Security Store (DSS)”.