The Blockchain Association filed an amicus brief supporting Wyoming-chartered Custodia Bank in its Supreme Court petition against the Federal Reserve. The legal battle challenges the Kansas City Fed’s 2023 denial of a master account, addressing whether regional central banks have unlimited discretion to block eligible depository institutions from core payment rails.
The Master Account Bottleneck and Legal Standing
According to CoinPedia and Coinalertnews, these accounts grant direct access to the central bank’s payment systems, allowing institutions to bypass costly intermediary correspondent banks. They also provide permanent status, a liquidity safety net, and the ability to earn interest on reserve balances.
Custodia Bank applied for this critical access in October 2020 under the leadership of founder Caitlin Long. More than two years later, in January 2023, the Kansas City Fed formally rejected the application. The regional reserve bank cited “undue risk” and crypto-focused business models as threats to financial stability. Custodia initially sued in June 2022 to combat the prolonged processing delay before moving forward to challenge the outright denial.
The legal trajectory has proven arduous for the digital asset bank. Lower courts repeatedly sided with the Federal Reserve, ruling that regional reserve banks retain discretion over these decisions. Custodia lost in district court in 2024 and suffered a defeat at the Tenth Circuit in 2025. By March 2026, the full appeals court denied an en banc rehearing by a 7-3 vote. This string of losses paved the way for Custodia’s Supreme Court petition, which was docketed on July 14, 2026, as Custodia Bank, Inc. v. Federal Reserve Board of Governors, et al.
Industry Implications and the Amicus Push
The core of Custodia’s Supreme Court argument centers on a strict interpretation of the Monetary Control Act. The statute dictates that Federal Reserve services “shall be available” to eligible nonmember depository institutions. Custodia asserts that this phrasing strips regional Fed banks of arbitrary veto power over legally compliant entities.
Crypto lobbying group the Blockchain Association stepped into the legal fray with an amicus brief to prevent what it views as systemic regulatory overreach. According to coverage from Coinalertnews, the industry group warned that lower court rulings establish a dangerous precedent, creating “a blueprint for federal regulators to debank disfavored industries or companies in the future without interference from state regulators.”
Advocates argue that unchecked federal discretion effectively locks compliant digital asset firms out of the traditional financial architecture. Without direct master account access, crypto institutions must rely on third-party intermediaries, introducing operational vulnerabilities, higher overhead, and unnecessary transaction friction.
Regulatory Shifts and Parallel Frameworks
The high-stakes Supreme Court filing coincides with a shifting regulatory landscape for digital asset banking. In March 2026, the Kansas City Fed approved a limited-purpose master account for the Kraken exchange. Unlike a full traditional master account, this restricted arrangement—often referred to as a “skinny” account—does not earn yield on Fed deposits, provides zero access to emergency discount window loans, and is restricted strictly to payment services on a one-year trial period.
Following this move, the Federal Reserve proposed a broader restricted payment account framework. It instructed regional Fed banks to pause Tier 3 master account decisions while that rulemaking process moves toward its conclusion on December 31, 2026. Meanwhile, the broader crypto industry continues to monitor parallel legislative efforts, including proceedings on the CLARITY Act, which aims to establish clearer statutory definitions for digital assets.
The Kansas City Fed’s response to Custodia’s Supreme Court petition is formally due by September 11, 2026. As the justices weigh whether to grant review, the case stands as a definitive test of statutory boundaries governing access to America’s central banking infrastructure.
