(CN) - Apple won another battle in its multipronged patent war against Google's Motorola Mobility after the U.S. International Trade Commission dismissed claims over an internal phone sensor.
The ruling effectively ends Motorola Mobility's three-year fight with Apple over six patents Motorola accused Apple of copying in the construction of the iPhone. Had Motorola been successful, the ITC could have halted imports of the iPhone into the United States from Apple's manufacturers in China.
It had looked into the case after Administrative Law Judge Thomas Pender invalidated the final patent in the dispute last year. Pender found Motorola could not patent a sensor that prevents unintended hang-ups and application launches when the phone is close to a person's face because of its similarity to other patents on the market.
On appeal, Motorola argued that it filed the patent in 1999 before mobile touch-screen devices dominated the market.
Motorola also noted that the late Apple co-founder Steve Jobs himself called the sensor a "breakthrough," though Apple argued he wasn't talking about the sensor patent directly.
For its part, Apple argued the sensor is similar to ones that prevent accidental dialing on keypads, predating Motorola's sensor technology.
The ITC ended its investigation Monday by reversing Pender's opinion of similarity. Instead, the agency accepted Apple's arguments and said the sensor patent is invalid for a lack of inventiveness.
This latest ITC action mirrors ones earlier in the drawn-out proceedings. A year ago, Judge Pender found that Apple had infringed Motorola's 3G wireless transmission patents, but the commission found that the technology is used industry-wide and dismissed Motorola's claims.
The war between Apple and Motorola wages on - and on multiple fronts - as Apple appeals the commission's earlier dismissal of its touch-screen technology claims. Bot companies are also challenging a federal judge's decision to toss their infringement suits against each other. And a federal judge in Miami presiding over another dispute called the companies "obstreperous and cantankerous" for using the courts as a business strategy instead of resolving their differences.
Google bought Motorola Mobility for $12.4 billion last year, largely to take on Apple and compete directly in the $51 billion U.S. smartphone market. By acquiring Motorola, Google also gained access to over 17,000 of the company's cellphone-related patents.
Apple dominates the U.S. smartphone market, with the iPhone accounting for 45 percent of all devices sold here last year.