A group of Tornado Cash users have appealed a ruling upholding the United States Treasury's decision to add the cryptocurrency mixer to its list of sanctioned entities. The appeal argues that the US Treasury "stretched its authority beyond recognition" in sanctioning Tornado Cash transactions. The plaintiffs claim that smart contracts under Tornado Cash identified in the lawsuit were "immutable and ownerless" and failed to meet the US Treasury's regulatory definition of "property" subject to sanctions. The appeal also challenged Treasury's definition of "interest," claiming Tornado Cash has no "legal, equitable, or beneficial interest" in users' smart contracts. Coinbase chief legal officer Paul Grewal has publicly supported the efforts of the plaintiffs.