A Legislative Turning Point: the 2025 HEAR Improvements Act and the Erosion of Traditional Defences in Cultural Property Litigation

Just think of the Cassirer, Zuckerman or Von Saher cases. All three were dismissed due to defences based on the passage of time, adverse possession, acquisitive prescription, or other such technical defences.

In response to these ongoing challenges, U.S. lawmakers recently proposed a bill that would give claimants of nazi-looted art a markedly stronger footing: The Holocaust Expropriated Art Recovery (HEAR) Improvements Act of 2025 (the “2025 Amendment”). This amendment is not so much a gentle revision but a sharpened scalpel to the procedural safety nets current owners have long relied upon.

If this 2025 Amendment passes, it will neutralise many procedural defences that have, until now, obstructed many claims. This blog explores the 2025 Amendment and the case law that inspired the proposed changes. 

Cassirer and California: Time for Federal Change?

In the (now infamous) Cassirer v. Thyssen-Bornemisza Foundation case, the Cassirer family sought restitution of a Pissarro painting looted by the nazis. The Californian courts were faced with a conundrum: to apply Spanish law (in favour of the Thyssen-Bornmisza Foundation) or to apply Californian law (in favour of the Cassirer family).

To resolve choice-of-law conflicts, California typically relies on a doctrine known as “comparative impairment”. This involves three steps. First, the court looks to see if the potentially applicable laws differ. Second, the court evaluates whether each jurisdiction has an interest in applying its law in the circumstances of the case. Third, the court compares the interest of each jurisdiction “to determine which state’s interest would be more impaired if its policy were subordinated to the policy of the other state.”

By applying the Californian “comparative impairment” doctrine, the court in that case preferred Spanish law, and the Thyssen-Bornemisza Foundation won the case on the basis that through adverse possession, it has become the owner of the painting. Thus, despite a strong claim on the merits, the U.S. courts ultimately denied the Cassirer family’s claim.  Had the Californian court applied Californian law, the Cassirer family could have won the case.

The decision caused an uproar within the Californian legal community and California quickly enacted a groundbreaking law (Assembly Bill 2867) which mandated that California’s substantive law must be applied apply to all claims brought under the HEAR Act of 2016.

This was seen as a way to break down procedural safety nets at the state level. Lawmakers now seek to do the same at a federal level.

The 2025 Amendment

Before the HEAR Act 2016 was passed, many legal claims for art looted by the nazis were dismissed due to a procedural barrier: statutes of limitation. These time limits often prevented courts from considering whether the claimant had a legitimate claim to the artwork based on merits. The HEAR Act of 2016 addressed this issue by establishing a uniform federal statute of limitations for such claims: six years from the time of “actual discovery.” This meant that the six-year clock would only start when a claimant truly became aware of both the artwork’s location and their right to reclaim it. Importantly, the HEAR Act rejected the principle of “constructive discovery,” which had previously allowed defendants to argue that a claimant should have known about the art's whereabouts simply because information had been made public. However, the HEAR Act includes a sunset clause.  It is set to expire at the end of 2026. The proposed 2025 Amendment seeks to eliminate this expiration date, ensuring that future claimants can continue to rely on the “actual discovery” standard in the future.

The 2025 Amendment also addresses the complex and contentious issue of foreign sovereign immunity in the context of nazi-era claims. The 2025 Amendment rejects what was decided in Federal Republic of Germany v. Philipp, where the U.S. Supreme Court was asked to consider whether the Foreign Sovereign Immunities Act (FSIA) allows U.S. courts to hear a case brought by German citizens against Germany for property allegedly taken during the nazi-era.

In Philipp, the plaintiffs were heirs of Jewish art dealers who, in 1935, sold a collection of medieval artifacts (the Guelph Treasure) to nazi-controlled Prussia for a fraction of its value. They argued the sale was coerced and constituted a taking of property in violation of international law.

The Court unanimously held that the FSIA’s "expropriation exception" (which allows lawsuits against foreign states for property taken in violation of international law) did not apply in this case. The Court reasoned that the exception was meant to address state takings of foreign nationals’ property, not property taken by a state from its own nationals, even under egregious circumstances. Since the plaintiffs’ ancestors were German nationals at the time of the sale, the FSIA barred the lawsuit in the U.S.

The 2025 Amendment seeks to clarify and potentially expand the scope of the “expropriation exception” by allowing claims to be against a foreign government, regardless of the nationality or citizenship of the alleged victim, notwithstanding the precedent established in Federal Republic of Germany v. Philipp.

The 2025 Amendment also proposes that lawmakers take a hammer to the “Act of State” Doctrine which was famously dealt with in the Von Saher v. Norton Simon Museum of Art case.

In Von Saher, the plaintiff sought to reclaim two oil paintings by Cranach that had been part of a collection forcibly sold by the Nazis during World War II, originally belonging to her father-in-law. After the war ended, the Allied Forces transferred the artworks back to the Dutch government. In 1966, the Dutch authorities sold the paintings which later ended up in the Norton Simon Museum.

The Court ultimately decided (by applying the “Act of State” doctrine) that acts of foreign sovereigns within their own jurisdictions were deemed valid. There was nothing a Court in the U.S. could do.

The 2025 Amendment proposes that the “Act of State” doctrine will not apply to cases brought under the HEAR Act.

Finally, if passed, the 2025 Amendment would eliminate other potential defences such as laches and forum non conveniens, which were not addressed in the HEAR Act of 2016.

The 2025 Amendment would also allow for retroactive application. Any pending lawsuits would, therefore, benefit from it.

The Amendment was put forward in May 2025.  It is making it way through the Senate and is expected to become law next year if the law is passed.

Achieving the Right Balance

Predictably, the proposed reforms have prompted debate. Critics argue that retroactively reducing the availability of procedural defences risks undermining legal certainty, particularly in cases where evidence is degraded or lost due to the passage of time.

Some are wondering whether the pendulum is swinging too far in support of restitution.  Most current owners of nazi-looted art bought the art inadvertently, in good faith, for full value, often prior to the late 1990’s at a time when issues of nazi-looted art were mostly ignored.  If the Court orders that the artwork be returned to the former owners, unless funds are available to compensate the current owner, is that a fair outcome? 

Just and fair solutions in the spirit of the Washington Principles are meant to achieve the right balance between the interests of former and current owners.  If the 2025 Amendment is passed, and former owners have the unrestricted right to recover art lost during the nazi-era, are we moving away from just and fair solutions? 

This is so difficult to get right when those responsible for tragic events can no longer be held accountable.  If the 2025 Amendment is passed, and other countries follow suit, is it not time to consider an international fund to compensate good faith current owners who, voluntarily or coerced by the Courts, give up the ownership of artworks they have cared for over many years?