Just because UTAU is freeware, it doesn't mean you can use it in any way you wish. The UTAU fandom has rules.

Yes, believe it or not, rules.

Ameya, the creator of the UTAU software himself, has written a set terms of use that can always be found in full English translation on the UTAU wiki. One of the most important of these, think of it as the Golden Rule of UTAU:

YOU MAY NOT IMPORT OTHER SYNTHETIC VOICES INTO UTAU, ESPECIALLY VOCALOID VOICES.

"But," you say, "wasn't there a Haku UTAU made at one time? What about Macne Nana, Acme Iku, or FLchan? What about Mikune Samu/Microsoft Sam? What about our beloved Google Translate Lady?!"

Macne Nana is legal to use in UTAU so long as you have purchased her voicebank legally. Same with Acme Iku.
And before you begin arguing about the others, please take this into account:


------


Many of users in the Spanish-speaking Vocaloid and UTAU community might know of Lionoid Lourdes and Sofia Fernanda. The creator, Ricardo Carrera (clandangosama on Youtube), openly promoted Lourdes as a LOLA fanmade, and likewise Sofia as a fan version of MEIKO. He publicized them on Youtube, on NicoNico Douga, and even on Piapro.

And yet, despite being "fanmades," these were both used as and listed as UTAUloids. The problem? Lourdes used LOLA's voice imported into UTAU, and Sofia was made the same way using MEIKO, though the creator repeatedly denied any such wrongdoings.

In what's probably the biggest show of fandom self-policing, Lourdes and Sofia were exposed for what they really were. The legal repercussions are not something to laugh at: Crypton and Piapro are involved in the Sofia/MEIKO case, and now Zero-G has been notified of Lourdes/LOLA. Videos of Lourdes and Sofia have been removed from NND, though it is unknown whether or not Ricardo himself did this, or if NND removed the videos. (Note: The "Lourdes" tag no longer appears to exist on NND.) All of his UTAUs/fanmades are now blacklisted from both the UTAU and Vocaloid Wikis.

Ricardo, having redistributed Vocaloid-based voicebanks at one point in time, has committed a serious offense of Vocaloid piracy. In terms of real life, should Crypton or Zero-G decide to take full legal action, it is most likely his parents that will suffer financially as a result, since he is a minor.


------


NOTE!! PLEASE DO NOT TAKE MATTERS LIKE THESE INTO YOUR OWN HANDS AND GO TROLL ANYONE OVER THIS. If you find people importing Vocaloid voices into UTAU, report them to people on the Vocaloid or UTAU Wikis.

Thank you.


Sources:
[link]
[link]
[link]