Zac just informed me that the Red Hot Chili Peppers are considering suing Britain’s X Factor finalists Diana Vickers for this similar hook in her 2010 song “My Wicked Heart”. Vickers even admits to it!

“That happened without even knowing! We had the song and it didn’t have the ‘My Wicked Heart’ bit in it and then we put the vocal in and we were like, ‘Why does it sound so familiar?’.”
“Then we realised it was because we were listening to ‘Under The Bridge’ the day before! We were saying, ‘Should we change it? Should we not? What should we do?’. Sod it, no, we’re just gonna keep it, it works, it’s the way it is.”
– digitalspy.com