What does DD mean online 12c on a w2?

In the context of a W-2 form, "DD" refers to the amount of employer-sponsored health insurance coverage provided to an employee, as reported in Box 12 with code DD. This amount is for informational purposes only and is meant to inform employees of the value of their health benefits, which may have implications for tax purposes under the Affordable Care Act. The figure does not affect the employee's taxable income.