Mars filed a preemptive lawsuit last Monday in the US District Court for the Eastern District of Virginia, asking a federal judge to dismiss Hershey’s claims, just days before Hershey filed its trademark infringement suit against Mars in the US District Court for the Middle District of Pennsylvania.

The companies have clashed previously over Mars’ use of an orange color that Hershey considered to be too similar to its trademark shade, after Mars sued Hershey for copyright infringement, among other claims. They settled out of court in August in a court-ordered settlement conference.

Hershey’s assistant general counsel, global IP, Lois Duquette sent Mars a cease-and-desist letter dated November 3, which said: “It can come as no surprise to Mars that Hershey, having objected to the color of the individual Dove peanut butter chocolate wrappers and filed a counterclaim to obtain a change of that color, would have a serious problem with Mars' revising the outer package to add orange as a substantial background color.”​

The Hershey Company objects to Mars’ use of orange as a predominant background color and has asked the company not to use color combinations of orange, yellow and brown/tan. It claims that a new packaging design for Mars’ peanut butter milk chocolate Promises, which features an orange diagonal wave against a brown background, constitutes trademark infringement and dilution, and unfair competition.

However, Mars claimed in its preemptive suit last week that Hershey has previously admitted that it does not have exclusive rights to use the color orange for peanut butter candy and that orange is commonly used in the confectionery industry as a generic flavor indicator for peanut butter.