Rift rumblings began last month, when the ornery actor, 50, flew solo at the Cannes Film Festival and was supposedly seen in the company of two "super-hot" ladies, one blond and the other brunette.
ScarJo, 26, who was first linked to Penn in January, a month after parting ways with Ryan Reynolds after two years of marriage, stayed put on the New Mexico set of "The Avengers."
Word of the breakup follows months of cozy sightings between the nicotine-fueled flames, who never actually confirmed they were an item.
The coupling was cemented when Sean invited Scarlett to be his plus-one to Reese Witherspoon's March wedding to CAA agent Jim Toth.
"They are totally head over heels in love," a source gushed to People in April. "They make each other feel good. They're both kind of unique and a little bit dark, but together they're a good match."
Just not good enough, it seems. Reps have yet to comment.
What do you think of Scarlett and Sean's bust-up? And who do you think the starlet should date next? Tell us in the comments.
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