Prince William has popped the question to his long-time girlfriend Kate Middleton! And what  if.. if Prince William divorces Kate, he can’t protect the royal fortune with a simple prenuptial agreement!

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Prenups aren’t legally totally binding in the U.K. — which means if William ever divorces Kate Middleton … she could own half of the kingdom.

We’re definitely not insinuating the marriage to be doomed … but if.. if things go south, money could be a HUGE issue … due to the fact that William’s grandma is reportedly worth around $450 million.

TMZ has spoken with multiple legal experts who specialize in U.K. family law — who say prenups have been considered virtually worthless, due to the fact that English law was based upon the idea that a married couple should be together for life and their property should be shared.

Translation — from the second a couple is married, they’re each entitled to half of the couple’s wealth … unless a judge decides the traditional 50/50 arrangement is unfair.

Now there is a catch — The Supreme Court of the U.K. recently made a landmark decision honoring a multi-million dollar prenup … and the ruling could change the laws regarding divorce agreements forever.

So what does that mean for William??? The experts tell TMZ that he’ll probably get a prenup anyway — just to be safe.

After dating for nine years, I think they can stick together in the long haul.. say till death do they part.. of course if they try hard enough. Relationships aren’t easy, we all know that, right?

photos: Fame

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