se entiende que este contrato pre nupcial sera un hecho desde que se celebra el matrimonio

Claims means a right of action or legalistically a 'chose in action', so una acción - not to be confused with a company share - or pretensión.

Matrimonio can also double as the parties as the married couple: entry 2. West and claims are more like entitlements than obligations.

correspondan : future subjunctive - correspondieren - might be more fitting here.

We also need to know what matrimonial property regime is being referred to e.g. joint vs. separate property in Anglo-Am law known as joint tenancy vs. tenancy-in-common or joint of 'after-acquired marital property' only > régimen de gananciales in Spanish law only. There are at least three other systems, including régimen de participación.