Do my parents have to claim me as a dependent to let me be on their health insurance?

I am still on my parents health insurance (because they have really good benefits) and I am a student and I also work full time. My issue is that my parents still claim me as a dependent therefore my tax returns suck PLUS I won't get the 2008 stimulus money. My parents insist that if they don't claim me I won't be able to be on their insurance. I don't see how the health insurance company would even know whether or not they were claiming me. Do my parents have to claim me as a dependent to have me on their health insurance?
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If their benefit plan states that you have to be a tax dependent to be insured, then yes...your parents would have to claim you. I work on dependent eligibility audits, and in the past 6 months I've had to remove somewhere between 200-300 dependents for various clients because they weren't able to show proof of claiming the child as a dependent on the taxes when I requested the documentation. Some of these people were also fined very heavily by their employers for trying to carry ineligible dependents. Now, this only applies if your parents benefit plan specifically states that you have to be claimed as a tax dependent. Some do state that, but most don't. But is it possible that your parents have to claim you as a tax dependent? Absolutely.
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