OIG has issued a reminder to Medicare participating physicians of the potential liabilities posed by billing Medicare patients for services that are already covered by Medicare. The OIG states that Medicare participating physicians can charge Medicare beneficiaries extra for items and services that are not covered by Medicare. Participating physicians may also charge beneficiaries for any Medicare deductibles and coinsurance without violating the terms of their assignment agreements. But when participating physicians request any other payment for covered services from Medicare patients they are liable for substantial penalties and exclusion from Medicare.