In a filing today in federal court, Megaupload founder Kim Dotcom stated that all artists involved in the now-infamous Megaupload video signed Appearance Consent and Release Agreements. Furthermore, Dotcom revealed that Black Eyed Peas frontman Will.i.am had assured him during a telephone call that contrary to suggestions in the press, he had not authorized the submission of DMCA takedown notices of Mega Song.

File-hosting service Megaupload sued Universal on Monday claiming that the label had sabotaged its viral advertising campaign. The Hong Kong-based company said that Universal wrongfully claimed copyright over the Mega Song, a promotional track commissioned by Megaupload which featured some of the biggest names in pop music.

After being launched Friday last week, Mega Song disappeared from YouTube and a whole host of other video services as a result of Universal-issued DMCA takedown requests. Papers filed in federal court today provide additional details on Megaupload’s complaint.

At the heart of Universal’s takedown is their assertion that Mega Song contained an unauthorized performance by New Zealand artist Gin Wigmore. Last week TorrentFreak learned that Wigmore’s vocals had been considered for the Mega Song, but in the end the decision was made to hire Macy Gray instead.

Wigmore has been described as having a vocal quality “somewhere between Amy Winehouse and Macy Gray”, which begs the question whether there is a case of mistaken identity at play here. In any event, Megaupload are absolutely clear – “Ms. Wigmore did not even appear in, much less author the Megaupload Video,” today’s filing declares.

Earlier this week, an article appeared in Hollywood Reporter titled, “Will.i.am Sends Takedown Notice Over Megaupload ‘Endorsement’ Video” in which it was claimed that Ken Hertz, attorney for Will.I.Am, filed a takedown request last week with YouTube.

But a statement from Megaupload founder Kim Dotcom today raises serious questions.

“On December 12, 2011, I spoke directly with will.i.am about this issue, and he personally advised me that he absolutely had not authorized the submission of any takedown notice on his behalf,” Dotcom explains.

THR also reported Hertz as saying that Will.i.am had never consented to appearing in the Mega Song, but considering documents filed today, that seems in doubt.

“Plaintiff obtained licenses from each of the persons who appeared in the Megaupload Video, including will.i.am,” the filing reads.

“In the agreement he signed, will.i.am explicitly waived any interest he may have in and to the copyright in connection therewith, agreeing that Plaintiff is its sole owner.”

Indeed, the agreement with Megaupload (signed under Will.i.am’s real name of Will Adams) seems particularly broad, granting the file-hoster the right to:

..copyright, record, reproduce, broadcast, distribute, edit, publish, exhibit, disseminate, couple and use in any way throughout the universe and in perpetuity the audio and/or visual portions of any videotape, film, pictures, negatives, prints, photographs, stills or other recordings of the Appearance, and any reproduction thereof.

While it’s clear that Megaupload had invested a substantial amount of money in creating the Mega Song and video, exactly how much remained unclear. Today it was revealed that the cost of production was in excess of $3 million, hardly surprising considering the huge names involved.

Megaupload say that Universal knowingly made false claims in order to sabotage the momentum of a viral campaign designed to boost the file-hoster’s image. Universal are yet to file an official response.