Slide to unlock was also on Windows CE in 2005, but Apple still claimed that Samsung stole it from them - and won.
And the multi-tasking interface that Apple does have was taken from WebOS/Palm Pre in 2009.
And Apple stole slide-from-top notification center from Android, and now Apple is "following" with larger screens, possibly NFC, etc.
For what it's worth, I'm totally FINE with all of the above. Competition borrowing and refining makes better interfaces. Apple's self-righteous stance in this area feels hypocritical since they steal just as much... going back to complaints about Windows copying Mac, when Mac was copied from Xerox in the first place.
Patents are on specific concepts and not general ideas. Samsung's attorneys were exaggerating when they claimed Apple was trying to patent the rectangle (for what it's worth, Samsung has design patents on rectangles with rounded corners, too, as do every car manufacturer).
I don't recall the specific slide-to-unlock concept on WinCE, though in Europe there was a phone that came out in 2006 that had it, and so Apple's patent there was invalidated.
As for Mac and Xerox, it's a myth that Apple "stole" Mac OS from PARC. Apple licensed it from Xerox, and offered them stock, which Xerox sold. Also, Apple made significant changes to the user interface. Microsoft, on the other hand, basically copied entire elements from Mac OS. Blame John Sculley, who gave Microsoft an open-ended license in exchange for a one-year exclusivity deal on the original Microsoft Office. Subsequent Apple management later tried the "look and feel" argument to attempt to limit the damage, but the courts disagreed. Microsoft got a little greedy again and copied QuickTime (to which it didn't have a license). That's how Steve Jobs was able to extract the agreement with Microsoft back in 1997 to continue writing Office for Mac and supporting Apple's development efforts. He threatened a $1 billion lawsuit and settled for something that proved far more valuable.
My guess is that is what Apple is after with Samsung. Remember, they settled with HTC, have a cross-licensing agreement with Microsoft, and a stand-still agreement with Nokia. They probably want a cross-licensing agreement with a "do not clone" clause. They have that with HTC, and it hasn't stopped HTC from building the One M8, which matches Apple's build quality and runs Android, but doesn't look like an iPhone clone the way the early Galaxy phones did.