How to make e-Signing interoperable

This presentations sorts out digital signatures and e-Signing and describes the current status of e-Signing, with its non-interoperable, cloud based workflows.

Can PDF turn e-Signing into an interoperable workflow? Can PDF carry proprietary data of the signing process and the audit-trail information? Can PDF help tracking the signing process, even outside of cloud e-Signing solutions, thus allowing the user to use his own favorite service, rather than being forced into the authors favorite e-Signing service?

If the ease of use of cloud based e-Signing could be moved into document based e-Signing using PDF, true interoperability could be achieved.

Of course, the presentation has suggestions on how to use PDF forms to get there. It also introduces the concept of a universal API for signature verification services.