XFDF

XFDF (XML Forms Data Format) is a format for storing and transferring data entered into a form in a PDF file. It is an XML-based alternative to FDF.

Specifications

 * XML Forms Data Format Specification, Version 3.0 (2009-08)
 * XML Forms Data Format Specification, Version 2.0 (2007-09)
 * XML Forms Data Format Specification Version 2.0 draft (2003-07)
 * XML schema