Grayscale Hyperliquid Staking ETF

Item 1.01. Entry into a Material Definitive Agreement. Additional Custodian; Custody Services Agreement On September 30, 2026, Grayscale Investments Sponsors, LLC, the sponsor (the “Sponsor”) of Grayscale Hyperliquid Staking ETF (the “Trust”), on behalf of the Trust, and BitGo Bank & Trust, National Association (“BitGo Trust”or the “Additional Custodian”), a national banking association chartered under the laws of the United States and authorized by the Office of the Comptroller of the Currency to exercise custodial powers, entered into an amendment (the “BitGo Amendment”) to the Amended and Restated BitGo Custodial Services Agreement (the “BitGo Trust Custodian Agreement”) pursuant to which the Trust became a party to the BitGo Trust Custodian Agreement. Pursuant to the BitGo Trust Custodian Agreement, BitGo Trust will provide services related to the custody and safekeeping of a portion of the Trust’s HYPE holdings. The Sponsor expects to utilize BitGo Trust’s services to custody a portion of the Trust’s HYPE. The Trust’s existing custody arrangement with Anchorage Digital Bank N.A. (“Anchorage Digital”) is unaffected by the Trust’s entry into the BitGo Trust Custodian Agreement, and Anchorage Digital remains the Trust’s primary custodian. The Sponsor shall, in its sole discretion, determine the amounts of HYPE held at either custodian as permitted by the Trust Agreement. At the current time, the Sponsor has not determined the amount of the Trust’s HYPE it will move to BitGo Trust. The addition of BitGo Trust reflects the Sponsor’s ongoing risk management approach as part of the Trust’s growing size. References to “the Custodian” in the Trust’s Registration Statement on Form S-1, as amended, the Trust’s Quarterly Report on Form 10-Q for the period ended June 30, 2026, and other filings with the Securities and Exchange Commission will be deemed to refer to Anchorage Digital, BitGo Trust and/or other custodians, collectively or in their individual capacities, as the context may require. With respect to the Trust’s HYPE held by BitGo Trust, upon Sponsor instruction, BitGo Trust will withdraw from the Trust’s account maintained with BitGo Trust the amount of HYPE necessary to pay the Trust’s Sponsor's Fee and any Additional Trust Expenses, consistent with the procedures described on page 115 of the Trust's prospectus, dated June 2, 2026, under “Business - Expenses; Sales of HYPE - Disposition of HYPE.” Fees paid to the Additional Custodian are a Sponsor-paid Expense. Under the BitGo Trust Custodian Agreement, the Trust’s HYPE held at BitGo Trust is held in a segregated Custodial Account, is not commingled with Digital Assets held for other clients or with BitGo Trust’s own assets, and the keys with respect to that account are held by BitGo Trust. In the event of a fork of the Hyperliquid blockchain, the BitGo Trust Custodian Agreement provides that BitGo Trust may temporarily suspend its operations and, in its sole discretion, decide whether or not to support (or cease supporting) either branch of the forked protocol entirely. The BitGo Trust Custodian Agreement requires the Trust to indemnify BitGo Trust, its affiliates, and their respective officers, directors, agents, employees and representatives against certain losses arising from or related to the Trust’s material breach of the BitGo Trust Custodian Agreement, among other things, except where a claim was caused by certain acts of BitGo Trust. The BitGo Trust Custodian Agreement also requires BitGo Trust to maintain insurance policies and coverage. The foregoing description of the BitGo Trust Custodian Agreement does not purport to be complete and is qualified in its entirety by reference to the full text of the BitGo Trust Custodian Agreement, which is filed with this Current Report on Form 8-K as Exhibit 10.1., and the BitGo Amendment thereto, which is filed with this Current Report on Form 8-K as Exhibit 10.2.