The act requires that health insurance companies not use underwriting to avoid insuring people likely to have health problems or with pre-existing conditions.

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In many states, small group insurance has group health underwriting, so if the small group has a bad history of claims, the insurance can be very expensive.

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Insurers have been doing this for centuries in underwriting health, auto, home and life insurance.

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The individual market for health care insurance is historically underdeveloped compared to the employer-sponsored market due to high costs, individual underwriting, and the ability of insurers to deny applicants based on pre-existing conditions.

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