I am open to 'Iron Man 4'

Robert Downey Jr. says he is open to an Iron Man 4.
The 49-year-old actor discussed his role in the future sequel in an interview with Entertainment Weekly. Marvel has confirmed a fourth movie in the series, but it is uncertain if Downey Jr. would reprise the role or be replaced with a different actor.
"It's down to Kevin [Feige, Marvel Studios president] and Ike [Perlmutter, Marvel Entertainment CEO] and Disney to come to us with what the proposal is, and that's on us to agree to disagree," Downey Jr. shared. "When things are going great, there's a lot of agreement."
"Right now, this has just been swell, hasn't it?" he said in reference to Iron Man 3's success. "This has been a really good one and it feels good and we're having a good time."
The first Iron Man movie premiered in 2008, with Iron Man 2 in 2010 and Iron Man 3 in 2013. The series has been enormously successful; Iron Man 3 raked in over $1.2 billion dollars alone. The character also starred in The Avengers (2012), and will appear in sequel Avengers: Age of Ultron in 2015.
"It's that thing of: Why give up the belt when it feels like you can barely get jabbed?" Downey Jr. posited before he added, "Most people are saying that right when they get knocked out... The future is, as usual, uncertain."
Avengers: Age of Ultron is scheduled for release May 1, 2015, and Marvel is expected to announce new movies and premiere dates this week at San Diego Comic-Con.