The bookmarks lead you to specific sections in an international standard. Perhaps it is helpful to think of it as a legal document. Go to Article 164, clause 504, section e, subsection i, ii, iii, etc. The text that follows is lengthy and detailed, too much for a bookmark. When I open the document I most likely am intending to go to a specific article/clause/section/subsection (i.e. 164.504.e.iii). So that's what is available in the bookmarks. All medical industry standards are arranged this way. It just so happens that the legal standard has a section ii that has subsections A, B, C ... up to I (iiI) and then has a separate section iii. Completely different sections, but one has an uppercase character in it and another doesn't. I can patch around this (make this case iiIa, for example), I just was checking what the rules are for case so I can see if there will be other conflicts like this.