Essential hasn’t yet shipped its first smartphone, but Andy Rubin’s new company has already come upon its first trademark dispute. Spigen, a fairly well-known smartphone case and accessory maker, has sent Essential a cease and desist letter demanding that Rubin’s latest business stop using the “Essential” mark. Spigen holds a trademark for the Essential mark that covers a slew of consumer products — though not smartphones directly. Android Police has a good writeup on the situation.

Spigen insists that Essential will “cause confusion” if the company moves forward with its launch of the Essential Phone. In the cease and desist letter, Spigen’s lawyers also point out that Essental had its trademark application denied by the US Patent and Trademark Office — not once, but twice — for this precise reason. In refusing the mark requests from Rubin’s latest business, the USPTO pointed to potential confusion between Essential and Spigen’s Essential sub-brand, which is already being used for a variety of battery packs and other smartphone accessories.

Spigen’s legal team is demading that Essential stop using the term “Essential,” and if a response isn’t received by June 15th, the accessory maker is “prepared to take any and all actions to protect Spigen’s marks.”

The likelihood of this being a major obstacle for Rubin’s Essential is small. It’s more so a nuisance that might require the company to write a check to take care of. But so far, Essential’s official response is that Spigen’s claims are “without merit” and the company plans to “respond accordingly.”

Welcome back to consumer electronics, Andy.