Under CURRENT law, if this person gets a job at Y company within 6 months, they cannot be denied coverage for a pre-existing condition. If the person gets a job at Y company after 6 months have passed, then they can only be denied coverage for a pre-existing condition for 12 months, after which, it must be covered. This is the current federal law, some states have different limits, but they cannot be worse than federal law, only better. (Maryland, for example, limits pre-exisiting condition clauses to 6 months rather than 12.)
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(1) I was referring to the supposed law in the mythic Land of sirs, where pre-existing condition exclusions appear to be sacred.
(2) If you have some forms of cancer, those 12 moths could easily be the difference between life and death.Curiously, I tend to side with life.