These are the outdated guidelines of SigiDoc, in their version 1.0 and 1.1, formerly stored on SourceForge (destined to be no longer used) and published at https://sigidoc.huma-num.fr/ (site that will soon no longer be the place where guidelines are published).
These guidelines are currently being updated to the 2.0 version in the framework of the DFG-ANR project DigiByzSeal "Unlocking the Hidden Value of Seals: New Methodologies for Historical Research in Byzantine Studies" ANR: https://anr.fr/Project-ANR-21-FRAL-0008; DFG: https://gepris.dfg.de/gepris/projekt/469385434. They are currently a work in progress and are available as Wiki in this same repository.