Apple and Samsung met four times in 2010 to try to prevent patent litigation11
The meetings took place at Apple's campus in Cupertino and at Samsung's home in Korea. It was in Korea, at an August 2010 meeting, that Apple representatives showed Samsung a presentation called "Samsung's Use of Apple Patents in Smartphones," which discussed two patents that Apple believed that the Korean based firm had infringed on. Obviously, Samsung's Attorney's were not impressed. It was Apple that fired the first salvo in April 2011 claiming that Samsung had used the look and feel of the Apple iPhone and Apple iPad with its own products. Samsung retaliated with its own suit and the game was on.
Ironically, Samsung is a major vendor for Apple and including the battery on the new iteration of the iPad, Samsung parts account for about 50% of Apple's third-gen tablet.
source: SBNation, TheVerge via AppleInsider