A little past 6 p.m. on Friday, May 18, the Internal Revenue Service finalized its rule implementing the tax‐​credit provisions of the Patient Protection and Affordable Care Act, better known as Obamacare. Though the statute expressly and repeatedly restricts “premium assistance tax credits” to states that create their own health insurance Exchanges, the IRS rule offers those tax credits through federal Exchanges. Those illegal tax credits will trigger so many other provisions of the law that the IRS rule is actually a massive and illegal tax increase. In states that do not create Exchanges, the rule will impose an illegal tax on employers of up to $2,000 per employee, and impose an illegal tax on individuals, with families of four paying $2,085 in 2016. This briefing will discuss why the IRS rule is inconsistent with the PPACA, how Congress can block it through the Congressional Review Act, how employers and individual citizens may block it through the courts, and how states can block it legislatively.