Apple has secured control of a critical patent that covers the downloading of music and video to a computer along with the capability of playing that content on another device, such as an iPod.

The company has reached an out-of-court settlement that Michael Starkweather, the lawyer responsible for the original patent holder's case, believes will affect "the future of the whole mobile phone, iPod and PDA industry. That's the billion dollar patent."

The case began in June 2005. During the litigation, Apple was accused of using the patent without permission, before an out-of-court settlement was reached, terms of which remain undisclosed.

Starkweather believes "Apple will eventually be after every phone company, film maker, computer maker and video producer to pay royalties on every download of not just music but also movies and videos."

If the patent had landed in the hands of Apple's competitors, it would have seriously threatened Apple.

Starkweather wrote the patent in 1996 for David Contois of Contois Music Technology. The concept consisted of a desktop computer holding multiple songs with an interface allowing a user to select three songs and play them on an electric grand piano. Starkweather saw the broader value and broke the patent into three elements: remote music storage, selection of music to download, and playing music on a music device.

Starkweather realised that downloading movies was an obvious variation to downloading music. It was data manipulated in the same way. "Sometimes it's easy to break an invention down to its key components," Starkweather says. "That's why patent writing is an art, not a science, and requires creativity."

Starkweather began his career as a Patent Examiner in the US Patent and Trademark Office, then served as in-house Patent Attorney for several major corporations, including Xerox, AT&T/NCR, Micron Semiconductor and IBM.

Currently, Starkweather is practicing patent law in Salt Lake City at his law firm, Advantia Law Group which he founded.