The pop superstar's lawyer, Laura Wasser, and her estranged husband's attorney, Mark Vincent Kaplan, started proceedings at Los Angeles County Superior Court on Monday morning.
TMZ.com reports Wasser will make a motion to keep the custody and spousal support orders secret.
Insiders claim the custody will stay at 50/50, despite recent claims Federline is pushing to win full custody of his sons as a result of Spears' recent erratic behavior--she stripped to her underwear for an afternoon swim in the Pacific Ocean and walked away from a magazine interview with thousands of dollars worth of clothes and accessories.
The couple split in November.
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