Apple has hit a hurdle in its three-year attempt to patent the menu-based software interface of its iPod, according to AppleInsider.

The patent application was rejected by the US Patent and Trademark Office last month.

"Standing in Apple's way appears to be a prior filing by inventor John Platt, who submitted a patent application for a similar software design for a portable device in May of 2002 - just five months before Robbin submitted his claims on behalf of Apple," the report explains.

The Register identifies Platt as a, "Microsoft Research scientist who used to work for touch pad vendor Synaptics".

His application explains "playlist generation based on seed items".

It was filed on May 30 2002, seven months after the iPod was revealed.

Apple's application reports iTunes engineer Jeffrey Robbins, Apple CEO Steve Jobs and vice president of marketing Phil Schiller as patent holding names. It was filed September 26 2002.