The legal kerfuffle between publisher Activision and former Infinity Ward studio heads Jason West and Vince Zampella just got uglier. Acti filed an amendment to its suit today that labels EA as a co-conspirator, seeking $400 million in damages.

Further, Activision calls the EA-funded venture Respawn Entertainment, which primarily consists of former Infinity Ward employees, as an “illicitly-created” operation. The suit places blame on EA for collaborating with Zampella and West ahead of their termination. Negotiations, allegedly, began as early as July 2009.

It also claims that EA’s top brass had a hand in the so-called conspiracy to lure Infinity Ward employees to Respawn. Here’s a few snips from the suit:

Unable to compete with Activision and Infinity Ward, and, upon information and belief, enraged by the recent defection of two Electronic Arts executives to Activision (unlike West and Zampella, the executives who left Electronic Arts were not under employment contracts), Electronic Arts was determined to retaliate. Electronic Arts set out to destabilize, disrupt and to attempt to destroy Infinity Ward. Although the precise dates the scheme was conceived and initiated remain somewhat unknown to Activision it was clearly underway no later than July 30, 2009.

Activision is informed and believes that the negotiations between Electronic Arts and West and Zampella were structured with the design and the expectation that West and Zampella would “spin out” from Activision and would take significant numbers of key Infinity Ward employees with them to set up their own independent company so that Electronic Arts could make another run at competing with Activision. Electronic Arts would finance the illicitly-created start-up in exchange for an ownership interest or exclusive distribution rights to the content created by their new company, which would produce video games for Electronic Arts instead of Activision.

EA has yet to comment on the filing.

Thanks, Gamasutra.

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