The Trump administration’s health-policy overhaul isn’t just playing out in agencies and press conferences — it’s being fought line-by-line in federal court.

Over the past year, Democratic-led states, medical organizations, providers, and advocacy groups have filed a growing stack of lawsuits challenging changes to vaccine guidance, research funding, health insurance rules, and reproductive health financing. Some of these cases have already produced major court orders; others are still winding their way through hearings and appeals.

Here’s the landscape of the biggest legal battles — and what each one is really about.

1) The Vaccine Overhaul Fight: RFK Jr.’s agenda meets a federal judge

The most politically explosive front is vaccines.

A federal judge recently blocked key elements of Health Secretary Robert F. Kennedy Jr.’s effort to reshape U.S. vaccine policy — including moves that would reduce the number of shots routinely recommended for children. The ruling sided with medical groups arguing that regulators acted unlawfully in implementing sweeping changes that could lower vaccination rates and harm public health.

This latest clash builds on earlier litigation from major medical organizations that sued over removals of certain COVID-19 vaccine recommendations from federal guidance for healthy children and pregnant women. The core issue in court isn’t whether vaccines work — it’s whether the administration can make large, system-wide changes without following required procedures and advisory structures.

Why it matters: Vaccine schedules don’t just guide parents — they shape school requirements, insurance coverage decisions, and public confidence. Even small changes can ripple outward fast.

2) NIH Research Funding Cuts: The “grant cap” lawsuit

In early 2025, multiple state attorneys general and medical associations sued over an attempt to cap or cut National Institutes of Health grant funding for scientific and medical research. A court deemed the cuts unlawful and blocked the policy.

After the funding cap was blocked, NIH indicated it would re-review grant applications that had been denied under the policy.

Why it matters: NIH grants are a backbone of the U.S. biomedical pipeline. Funding shifts don’t just affect labs — they can reset what gets studied, who gets hired, and what discoveries arrive years later.

3) NIH Grant Terminations: The anti-DEI directive cases

A separate wave of lawsuits targeted NIH’s termination of research grants deemed inconsistent with the administration’s anti-DEI directive. A federal judge ruled the directive illegal, and later NIH reached a settlement with multiple states agreeing to re-review thousands of applications that had been withheld or terminated.

Parts of that broader ruling remain under appeal, and the legal fight continues over how much power the administration has to attach ideological conditions to research funding.

Why it matters: This isn’t only about DEI language — it’s about whether research priorities can be reshaped through executive directives that effectively rewrite grant eligibility.

4) Planned Parenthood Defunding: Medicaid reimbursements as the battleground

Planned Parenthood sued over a provision in a federal tax and policy bill aimed at stripping funding from its health centers by blocking Medicaid reimbursements. After an appeals court allowed the funding ban to proceed, Planned Parenthood dismissed its federal lawsuit — but state-led challenges and related litigation remain active.

Why it matters: Medicaid reimbursements are not symbolic funding; they are operational oxygen for many clinics. Restricting them can reshape access to reproductive and preventive care at scale.

5) ACA Marketplace Rules: The lawsuit over coverage losses and enrollment limits

A coalition of Democratic attorneys general sued to block an HHS rule that the administration estimated could cause up to 1.8 million people to lose Affordable Care Act coverage. The rule is also challenged for increasing premiums and out-of-pocket costs, shortening enrollment periods, and removing gender-affirming care from “essential health benefits.”

That case remains pending, while a separate lawsuit succeeded in obtaining a preliminary injunction blocking several key provisions of the rule.

Why it matters: ACA marketplace rules decide who gets covered, when they can enroll, and what plans must include. Small regulatory changes can produce large coverage losses — and shift costs onto families.

6) “Transgender Grant Conditions”: States challenge federal spending strings

A group of Democratic state attorneys general sued over new conditions placed on federal grants that they say would force discrimination against transgender Americans. The lawsuit argues the administration is unlawfully using spending rules to impose policy goals that Congress did not authorize.

The case remains pending.

Why it matters: This is about more than one grant program — it’s a test of how far an administration can go in reshaping social policy by attaching conditions to federal money.

7) Multi-state vaccine schedule lawsuit: a second front still moving

Separately, a multi-state lawsuit challenges changes to the federal childhood vaccine schedule that removed universal recommendations for several vaccines. Medical organizations argue those shifts could depress vaccination rates and increase outbreaks.

This case is still pending — and could become even more consequential depending on how courts define agency authority over national vaccine guidance.

The bigger takeaway

These cases reveal a pattern: the administration is trying to move fast through agencies, and opponents are trying to slow, block, or reverse those moves through the courts.

Some lawsuits are about procedure — whether rules were followed.
Some are about power — who gets to decide national health policy.
And some are about consequences — who loses coverage, funding, or protection when policy shifts land.