It is possible to insert dynamic links in the PDF output created by InterForm400 with a special &&URI command in the spooled file.
You insert the special &&URI command as text in the input spooled file, that you use for a merge with an overlay or overlay selector. The command can e.g. be inserted via a split definition or page builder program. No other text can be placed in the same spooled file line, and the command line cannot be the first non-blank line on the page.
The prerequisites should be observed.
There are many other commands, that you can add to the input spooled file.