California v. Texas, 593 U.S. 659

The Affordable Care Act (ACA) originally required most individuals to maintain "minimum essential coverage" and imposed a penalty for noncompliance (26 U.S.C. §5000A); the Tax Cuts and Jobs Act of 2017 set that penalty to $0 effective 2019.
Texas (and 17 other States) and two individuals sued federal officials seeking a declaration that §5000A(a) (the individual mandate) is unconstitutional and that the rest of the ACA is inseverable and therefore invalid.
The District Court found the individual plaintiffs had standing, held §5000A(a) unconstitutional and nonseverable, and enjoined the ACA; the Fifth Circuit affirmed standing and unconstitutionality but remanded on severability.
The United States (federal defendants) agreed the mandate is unconstitutional; California and other States intervened to defend the ACA; the Supreme Court granted certiorari.
The Supreme Court disposed of the case on standing: it held neither the individual plaintiffs nor the state plaintiffs demonstrated an injury fairly traceable to enforcement of the challenged statutory provision, and thus lacked Article III standing; the Court remanded with instructions to dismiss.

Issue	Plaintiff's Argument	Defendant's Argument	Held
Standing of individual plaintiffs to challenge §5000A(a)	Hurley & Nantz: pocketbook injury from buying insurance required by the statute	Government: mandate now unenforceable (penalty $0); no government action causing injury	No standing — injury not fairly traceable or redressable because §5000A(a) lacks enforcement; declaratory relief alone insufficient
Standing of States for increased costs from more Medicaid/CHIP enrollment	States: mandate caused more enrollments and higher state costs	Government: any enrollment link is speculative, and mandate without penalty provides no enforcement incentive	No standing — claims rest on speculative third‑party choices; evidence insufficient to show predictable reaction
Standing of States for direct administrative/reporting costs (§6055/6056, employer mandates, adult‑child coverage)	States: reporting, employer mandates, and coverage obligations impose real costs tied to ACA	Government: those costs arise from other, independently enforceable ACA provisions, not §5000A(a)	No standing — alleged pocketbook injuries traceable to other provisions, not enforcement of §5000A(a)
Severability of §5000A(a) from the rest of the ACA	Plaintiffs: mandate is inseverable; if mandate invalid, many ACA provisions fall	Intervenors/Govt: mandate is severable from many ACA provisions	Not reached — Court resolved the case on standing and did not decide severability or the mandate's constitutionality

DaimlerChrysler Corp. v. Cuno, 547 U.S. 332 (standing requires injury fairly traceable to defendant)
Allen v. Wright, 468 U.S. 737 (traceability requirement for standing)
Lujan v. Defenders of Wildlife, 504 U.S. 555 (injury in fact and traceability principles)
MedImmune, Inc. v. Genentech, Inc., 549 U.S. 118 (declaratory judgments must satisfy Article III)
Whitmore v. Arkansas, 495 U.S. 149 (pocketbook injury can satisfy injury in fact)
Babbitt v. United Farm Workers Nat. Union, 442 U.S. 289 (standing requires injury from statute's enforcement)
Susan B. Anthony List v. Driehaus, 573 U.S. 149 (threatened enforcement must be substantial for standing)
Clapper v. Amnesty Int'l USA, 568 U.S. 398 (speculative chains defeat standing)
National Fed'n of Indep. Business v. Sebelius, 567 U.S. 519 (ACA precedent addressing the individual mandate and severability issues)
King v. Burwell, 576 U.S. 473 (statutory interpretation and ACA structure)
Steel Co. v. Citizens for a Better Environment, 523 U.S. 83 (jurisdictional limits and merits distinction)
Massachusetts v. Mellon, 262 U.S. 447 (injunctive relief operates against officials; jurisdictional limitations on preventive relief)