Can a health insurance company take more money from your salary, despite not having a contract with them?

Would prefer a little more than a yes or no answer.
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No, they can't access your paycheck without a court order. But, if it's your EMPLOYER taking the money from your paycheck, to forward to the health insurance company, yes, they can. Employers aren't required to contribute ANYTHING towards your insurance. They can change how much they contribute (thus changing how much you have to pay) with no notice. And they don't have to notify you if the insurance company's rate goes up, either.
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