Bill and Melinda Gates have signed a separation contract
In their divorce filing, Bill and Melinda Gates make it clear that they have no prenuptial agreement - but the papers make repeated reference to a 'separation contract' which will divide up their estate.
A separation contract, or separation agreement, is a legally binding document drawn up by divorcing couples in advance of their split in which they agree how to split their lives - including child custody and access, debts and property.
It is governed by contract law, meaning that either party can sue the other for breach of contract if the agreement is broken.
Signing a separation contract allows a couple to divide their assets by mutual agreement, rather than having to go to court.
For the average couple, this means saving money in lawyers' fees. For Bill and Melinda Gates, it avoids a lengthy, public process during which details about their private lives an assets may have been revealed.
However, a separation agreement is not necessarily final and a judge may overrule it if they feel the contract is unfair to the children involved, unfair to one of the partners, or that one partner has not fully disclosed their assets or earnings to be divvied up.