1,586. The Universal Practice Regarding Movable Property
Hilchos Ishus 16:8
The Rambam says that in all the communities he has ever heard of, the universal practice has become to write a kesubah so that it can be collected from both real estate and movable property. This is a great enactment, instituted by very wise men, because it is a financial condition. This enables a widow to collect the value of her kesubah from movable property by virtue of this condition rather than by rabbinic decree.
Hilchos Ishus 16:9
If this condition was not included in the text of a kesubah with the result that a couple married without such an arrangement, then if the husband was aware of this rule instituted by the Gaonim, the wife can collect from movable property. If he was not aware, or if we don’t know if was aware, then the matter must be thoroughly evaluated. This is because a rule of the Gaonim doesn’t have the authority to take money from the husband if he didn't make such a condition. The conditions of the kesubah are different in this authority because the kesubah was instituted by the Sanhedrin.