2008.06.12 18:46 "Re: [Tiff] Re: color profile management other than ICC", by Phil Harvey
Judging from the lack of Google hits, it seems to be proprietary and undocumented. So, having got one, what do you do with it?
You are right, the documentation isn't freely available, so it is of little use to individuals. Even Adobe products don't use this information unless you install the Epson-sponsored PrintIM plug-in. But presumably one could pay for a license if they were slightly insane and had far too much money on their hands.