The company filed for the trademark shortly after launching the device in October, but in a letter sent to Apple in January, the USPTO reviewer argued that the name was "merely descriptive."
In denying the application, the reviewer wrote: "Registration is refused because the applied-for mark merely describes a feature or characteristic of applicant's goods."
Apple already owns the trademark for the iPad in the US, but the USPTO believes the addition of "mini" does not do enough to give it "distinctiveness" and earn a separate mark.
Breaking it down
The reviewer also broke down the smaller device's name to argue that the parts "i" (internet device) "Pad" (tablet computer) and "mini" (something smaller then other members of its class) were all descriptive.
Apple, which has faced a global battle to register the iPad name, has until June to adapt its filing or the application will be officially shot down.
If it can convince the USPTO that the iPad mini name does indeed fall under the "distinctiveness" clause mentioned above then the company may yet be successful in its application.
The letter read: "If applicant believes that a portion of the mark has acquired distinctiveness, applicant may amend the application to add a claim of acquired distinctiveness as to that portion under Trademark Act Section 2(f)."
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A technology journalist, writer and videographer of many magazines and websites including T3, Gadget Magazine and TechRadar.com. He specializes in applications for smartphones, tablets and handheld devices, with bylines also at The Guardian, WIRED, Trusted Reviews and Wareable. Chris is also the podcast host for The Liverpool Way. As well as tech and football, Chris is a pop-punk fan and enjoys the art of wrasslin'.