It is entirely possible that, over time, standard usages of type arise outside the IVES Standard Types. There is nothing in the schema to enforce people utilising the IVES Standard Type and alternative standards may exist in parallel for describing different types of data, or describing it in different ways. However, it would be good if 3rd parties utilised an IVES Standard Type if there was one available, and if there wasn't then to approach IVES about the possibility of creation of a new one before taking matters into their own hands and defining their own standard.