What happens when someone doesn't disclose a pre-existing condition on their health insurance?

Is there a statute of limitations for that. Let's say for example it's been ten years they had the policy.
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This is what's wrong with the American Medical System and their insurance. In Australia you can be covered for a pre-exsisiting condition, even one that you or your Doctor didn't know about at the time, say something you were born with that develops at age 30. But In the USA they won't cover you for anything pre-excisting. It's all wrong really. From my friends that I have talked ti on the USA with trouble getting insurance, it doesn't make any difference how long you have the condition. ANYTHING that's going to cost THEM money, they will never cover.
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