Newspaper publisher Phil Bronstein said he and Stone will have joint custody of their adopted 3-year-old son, Roanm, Zap2it.com reported Thursday.
Rumors surrounding the impending break-up have pointed to Stone's attempt at reviving her movie career as a reason for stress in the marriage.
She is currently filming a period romance opposite Rupert Everett in London called "A Different Loyalty."
The actress has been married twice before and has previously been linked romantically to Dwight Yoakam and producer Bill Macdonald.
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