How fucking stupid are you people. All assets acquired before a marriage are not joint assets.
If the marriage is out of community of property and subject to the accrual system, then on divorce, the wealth accumulated during the marriage is shared.
A regular prenup contract automatically falls under the accrual system, unless specified in the contract that it is not to fall under the accrual system.
So unless you specified this in the contract, everything attained after the marriage is shared.