Citing irreconcilable differences in Friday's filing, Harper asked the judge to deny Dern spousal support, the Web site TMZ.com reported.
The filing said the couple separated in January, but people connected with the couple told TMZ they were living and traveling together as recently as last week, the report said.
Harper wants joint legal and physical custody of the couple's children, Ellery, 9, and Jaya, 5.
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