Board Thread:General Discussion/@comment-199.96.182.188-20130521215014/@comment-3076833-20130521224500

The difference between her and the UTAUs you mention are the fact that Teto and Co were made as a fan joke. Mitsuko on the other hand :


 * Went under the Vocaloid name but only in a more serious manner; i.e. not as a simple joke


 * Was advertised as a Vocaloid even though it had an UTAU bank in her name (Teto gave up her title as a Vocaloid when she went UTAU in comparison, heck even long before that happened)


 * Was used commercially under the Vocaloid name (In other words money was involved)


 * Infringed the copyrights of both fan arts and mmd models (As described on her wiki page here)

TL;DR : Unlike Teto there is far more legal concerns with Mitsuko, even if she is UTAUed (Assuming she is using the thing, there are concerns about that too).