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When it comes to the official Vocaloid characters the items are not official, though at times official companies may acknowledge the fandoms activity by incorporating an item in announcements or various merchandise. There has yet to be one company that states a character item as official.

When it comes to fanmade characters the items are official by who ever created the character. Even though character items are not highly necessary, it has caught on with fanmade Vocaloids, Utauloids, and other Vocaloids after Miku's item reveal.