Apple wins patent on key smartphone feature

By:  Kim Peterson

Other software companies have incorporated the slide-to-unlock system, potentially leaving themselves open to lawsuits.

If you have a smartphone, you've probably used the slide-to-unlock feature to make a call or check your mail. This week, Apple (AAPL +0.06%) won the patent for that feature.

Apple first applied for the patent in 2005 (you can read the patent here), long before the first iPhone was unveiled. The idea is simple: A device with a touch-sensitive display may be unlocked via gestures performed on the touch-sensitive display.

Apple co-founder Steve Jobs had a little more fun describing it in 2007: "To unlock the phone, I just take my finger and slide it across," he said in a presentation. "Wanna see that again? We wanted something you couldn't do by accident in your pocket. Just slide it across -- BOOM!"

Slide-to-unlock is an elegant, useful feature, and it's been copied by many other companies. The Android software by Google (GOOG +0.25%) uses it, as does the new Windows 8 lock screen from Microsoft (MSFT -0.99%). (Microsoft owns and publishes Top Stocks, an MSN Money site.)

So what will happen now that Apple owns the feature? Well, it's pretty clear that any devices using it could be sued for patent infringement. Time Magazine thinks we'll see a substantial drop in the number of devices offering it from now on.

Apple isn't saying anything about this publicly. But we might look to Jobs himself for clues about the company's legal strategy here.

In the new biography of Jobs out this week, he says he was "willing to go thermonuclear war" on Android. Google's copying of Apple's features amounted to "grand theft," he added.

He also said he would "spend every penny of Apple's $40 billion in the bank to right this wrong."

So I'm guessing Apple's lawyers are getting ready for a big fight.