MM~LAW is co-counsel with other US law firms on behalf of American victims of terrorist attacks perpetrated by Hamas in Israel. The lawsuit alleges that National Westminster Bank knowingly provided material support and financial services to an entity in the UK which was designated by the United States, under Executive Order 13224, as Specially Designated Global Terrorist. Despite the designation, National Westminster Bank continued to provide banking services, including converting currencies to US dollars and easing transfer of funds to Hamas entities in Gaza and the West Bank, in violation of the US Anti-Terrorism Act. The case was dismissed on 28 March 2013 and appealed to the US Court of Appeal for the Second Circuit.

On 22 September 2014, the Second Circuit vacated the judgment of the District Court and remanded the case to the District Court. In its opinion, the Second Circuit Court said that "the statute's requirement is less exacting, and requires only a showing that NatWest had knowledge that, or exhibited deliberate indifference to whether, Interpal provided material support to a terrorist organization, irrespective of whether Interpal's support aided terrorist activities of the terrorist organization. As Hamas is an organization designated as a Foreign Terrorist Organization ("FTO") by the United States Secretary of State, Plaintiffs can fulfill this burden by demonstrating either that NatWest had actual knowledge that Interpal provided material support to Hamas, or that NatWest exhibited deliberate indifference to whether Interpal provided material support to Hamas."