It's interesting how it's Apple that mostly did everything and how the summary led people like you to mention only Microsoft. Typical biased Slashdot bullshit.
Not to mention other companies are part of Rockstar like RIM, EMC, Ericsson, Sony. Apple bought some patents from Rockstart in 2012 for like $1B.
By the fifth round of bidding, it was Rockstar Bidco that decided not to submit a bid. This brought the group of bidders down to three: Google, Apple, and Intel.
Then something really interesting happened.
Following Rockstar’s seeming exit, Apple asked Nortel for permission to talk to the group about a possible partnership. This request was granted. Following these discussions, Apple decided they wanted to partner with Rockstar and adopt their name and transaction structure.
Essentially, Apple decided to stake the Rockstar group in this high-stakes poker game.