Mark continues working after the age of 65 and is covered through his employer's group health plan. Which of the following statements is TRUE?

In the context of Mark's situation, who is over the age of 65 and continues to work while being covered by his employer's group health plan, the correct statement pertains to the coordination of benefits between his group health plan and Medicare.

When someone continues working beyond the age of 65 and is enrolled in their employer's health plan, that plan will be the primary payer as long as the employer has 20 or more employees. This is because the employer-sponsored insurance is intended to provide coverage first. Medicare, in this scenario, will serve as the secondary payer.

This means that if Mark were to incur health expenses, his group health plan would pay benefits first, and then Medicare would cover any remaining eligible expenses. Therefore, stating that Medicare is the secondary payer accurately reflects this arrangement. This is a crucial aspect of understanding how insurance benefits work for those who are both employed and eligible for Medicare.