George, 29, filed the dissolution in Los Angeles Superior Court on Friday, PEOPLE confirms.
Reps for Penn and George did not immediately respond to PEOPLE's request for comment.
Penn, 61, and George tied the knot in July 2020, during an intimate ceremony with only a few loved ones present. Rumors of their nuptials started swirling when they were spotted wearing gold rings. Their friends later started congratulating them on Instagram before Penn confirmed the news.
"We did a COVID wedding. By that I mean it was a county commissioner on Zoom and we were at the house, my two children and her brother. And we did it that way," the actor said on Late Night with Seth Meyers a month later.
Though Penn and George have been romantically linked since 2016, a friend of the actress told PEOPLE in August following their nuptials that the pair had reunited earlier in 2020 after a stretch of being on and off.
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"They got together and then they broke up, and Sean won her back," said the source. "He realized he had made a mistake and when he felt he might lose her, he worked hard to get her back."
The insider added that the time self-isolating together during the pandemic helped strengthen their connection. Penn and George even embarked on humanitarian efforts with each other throughout the public health crisis, including helping set up testing sites in Los Angeles.
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"They got back together during COVID and became really close and got engaged a few months ago, early during quarantine," the source explained.
The actor has two children from his marriage to Wright: daughter Dylan, 28, and Hopper.
TMZ was first to report the news of the Penn and George's split.