And there's no prenup (they were married in 1980), so his $900 million willprobably be split 50/50. Gibson's wife Robyn is also asking for joing physical and legal custody of their child Tom (the only minor in their brood totaling 7), as well as spousal support and attorneys.

That doesn't really make sense to me. If you're the one filing for divorce, shouldn't you have to pay for your own fucking lawyers? Anyway, the papers she filed site "irreconcilable differences" and the date of separation is listed as "to be determined," which could be fought over later, since the date of separation is the date that earnings cease to be considered under the 50/50 split of finances. 

Bummer too... they've been married 28 years. Ah well. Shit happens.