Complex sentence: The ACA legislation includes the language "enrolled in through an Exchange established by the State under 1311" where the IRS regulation implements a more broad definition encompassing both the state exchanges and the federal exchanges set up under section 1321.
Split into simpler sentences: The ACA legislation includes the language "enrolled in through an Exchange established by the State under 1311". As implemented by the IRS, ACA regulations use a more broad definition encompassing both the state exchanges and the federal exchanges set up under section 1321.