JWT’s honeymoon with Microsoft has apparently come to a screeching halt as the agency and its parent WPP are being sued by Delaware-based ad firm Denizen for a recent Bing spot that ties into NBC show The Philanthropist.

According to Brand Republic, Denizen met with WPP back in 2002 to discuss business ventures including program-integrated advertising and partnerships with WPP media agencies. Though talks eventually fell through, both parties signed a confidentiality agreement in 2006 to keep their convo on the QT.

Now, with The Philanthropist promo, Denizen is claiming JWT has ripped off its overall concept of melding a TV show’s content and characters with advertising while also jacking proprietary information and trade secrets for creating such ads.

When pressed for comment, JWT wasn’t talking, instead referring us to the powers-that-be at MS and WPP.

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