President Joe Biden signed the Inflation Reduction Act into law Tuesday, completing a compressed legislative push that gives Democrats their largest climate-policy victory to date while changing Medicare drug pricing, extending Affordable Care Act subsidies and imposing new taxes on large corporations.

The measure, enacted as H.R. 5376, passed the Senate on a party-line vote with Vice President Kamala Harris breaking the tie and cleared the House days later. Biden’s August 16 signing turns a proposal negotiated primarily by Senate Majority Leader Chuck Schumer and Sen. Joe Manchin into law just months before the midterm elections.

Climate and energy dominate the spending side

The law devotes hundreds of billions of dollars to energy security, clean-energy production, consumer incentives and emissions reduction. It uses tax credits and grants rather than a single national mandate, seeking to accelerate investment in solar, wind, batteries, electric vehicles, efficiency and domestic manufacturing. Supporters describe it as the most significant federal climate legislation ever enacted.

Sen. Sheldon Whitehouse, one of the chamber’s leading climate advocates, said after passage that the bill would materially bend the U.S. emissions curve. His August 7 statement highlighted methane controls, efficiency incentives, carbon capture and clean-energy deployment as major elements of the package.

The law also provides incentives intended to build more of the clean-energy supply chain in the United States. Those provisions complement the CHIPS and Science Act signed a week earlier, giving the administration two major industrial-policy laws aimed at shifting strategic manufacturing and investment toward domestic production.

Medicare gains negotiating authority

Health policy is the second major pillar. The law allows Medicare to negotiate prices for a limited number of high-cost prescription drugs, with the first negotiated prices scheduled to take effect later in the decade. It also caps annual out-of-pocket prescription-drug costs for Medicare beneficiaries and extends enhanced Affordable Care Act premium subsidies.

Sen. Bernie Sanders, who argued that the legislation did not go far enough, nevertheless said the drug provisions represented a meaningful break with longstanding policy. In his passage statement, Sanders noted that Medicare would finally gain direct negotiating authority, though initially for only a limited number of medicines.

The health provisions also include an insulin copay cap for Medicare beneficiaries. A broader cap for privately insured patients did not survive the Senate’s reconciliation process. The result leaves the law with substantial but narrower drug-cost changes than some Democrats originally proposed.

Corporate taxes and deficit claims

To finance the package, Congress created a 15 percent corporate minimum tax based on financial-statement income for certain large companies, increased funding for Internal Revenue Service enforcement and added a 1 percent excise tax on corporate stock buybacks. The law does not raise the statutory corporate income-tax rate across the board.

The Congressional Budget Office estimated that the Senate version would produce a net deficit reduction over the 2022-2031 period before later changes were fully incorporated. CBO also cautioned that the bill’s near-term effect on inflation would be small, a point Republicans repeatedly cited in arguing that the measure was improperly named.

Republicans opposed the legislation unanimously in the Senate. Sen. Bill Cassidy, for example, said in an August 7 statement that the legislation would not meaningfully reduce current inflation and criticized the corporate-tax and spending provisions. Other Republican senators focused on the additional IRS funding, energy policy and the economic effects of the book-income minimum tax.

A narrow path through Congress

The final Senate vote required every Democratic caucus member plus Harris. Sen. Angus King’s account of the vote emphasized the package’s combination of drug costs, climate investment, corporate taxes and deficit reduction. The House then accepted the Senate text without changes, avoiding another round of negotiations that could have disrupted the agreement.

The law is far smaller than the social-spending and climate package Democrats pursued in 2021, but its passage is consequential because it resolves several policy fights that had remained stalled for years. Medicare drug negotiation had repeatedly failed in Congress. Major federal climate legislation had likewise eluded lawmakers despite growing investment by states and private companies.

The enacted Public Law 117-169 now shifts attention to implementation. Treasury will need to write tax rules, the Department of Health and Human Services will develop the Medicare negotiation process, and energy agencies will distribute grants and establish programs tied to the clean-energy provisions.

Whether the law reduces inflation in the near term is likely to remain politically contested. Its more measurable effects will unfold over years through energy investment, prescription-drug policy, tax collections and federal deficits. What is clear this week is that Congress has enacted a durable package touching climate, health care and taxation after a year in which the broader agenda repeatedly appeared dead.