yeah he said on The Daily Show he was negotiating for more money,saying it with a wink and accompanied by Stewart laughing
Seriously speaking, it sounds like Marvel/Disney doesn't want to give Downey Jr. percentage points on box office anymore as salary. I would attribute that partially to Marvel/Disney being Scrooges, but also perhaps they don't want Hemsworth, Evans etc. to get similar ideas.
IM3 has topped $1 billion globally, so supposedly he gets more than $50 million at this point.
It all is incomprehensible to me, but probably they'd be more willing to just give him a flat $25M or $30M check - for one movie - but skip percentage points of total box office. Can you imagine?
Now, pre-Iron Man and pre-Sherlock Holmes, Marvel Studios probably felt that giving Downey Jr. some percentage points was an easy risk. He seemed washed up, had no track record at that point, how could it hurt? Oops