Uber Technologies Inc. has filed a lawsuit against Fetch Media Ltd., a mobile ad agency owned by ad giant Dentsu Inc., alleging the agency misrepresented the effectiveness of its mobile ads, failed to prevent ad fraud and didn’t return rebates owed to Uber.

The ride-hailing company is suing Fetch for breach of contract, fraud and negligence, among other allegations.

In the complaint, Uber said it hired Fetch to purchase and place mobile ads that direct potential new riders and drivers to download the Uber app. Uber said it only pays for ads that lead to app installations, new sign-ups or first trips. Fetch coordinated multiple ad networks to purchase ad inventory from a variety of publishers on behalf of Uber, according to the suit.