Grayscale Bitcoin Mini Trust (BTC) updates Coinbase and BNY Mellon agreements

Rhea-AI Filing Summary

Grayscale Bitcoin Mini Trust ETF reported that its sponsor, Grayscale Investments Sponsors, LLC, entered into a new Coinbase Prime Broker Agreement on October 3, 2025. This agreement governs custodial and prime brokerage services for the Trust’s bitcoin, provided by Coinbase, Inc., Coinbase Custody Trust Company, LLC, and Coinbase Credit, Inc.

The Trust also implemented a new Fund Administration and Accounting Agreement with BNY Mellon Asset Servicing, effective October 9, 2025, under which BNY continues to deliver administrative and accounting services. In connection with these changes, earlier prime broker and fund administration agreements dated in 2024 were terminated and replaced by the new contracts.

8-K Event Classification

3 items: 1.01, 1.02, 9.01

3 items

Item 1.01 Entry into a Material Definitive Agreement Business

The company signed a significant contract such as a merger agreement, credit facility, or major partnership.

Item 1.02 Termination of a Material Definitive Agreement Business

A significant contract was terminated, which may affect business operations or revenue.

Item 9.01 Financial Statements and Exhibits Exhibits

Financial statements, pro forma financial information, and exhibit attachments filed with this report.

Understanding 8-K Material Events →

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UNITED STATES
SECURITIES AND EXCHANGE COMMISSION
WASHINGTON, D.C. 20549

FORM 8-K

CURRENT REPORT

Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934

Date of Report (Date of earliest event reported): October 3, 2025

Grayscale Bitcoin Mini Trust ETF

(Exact name of Registrant as Specified in Its Charter)

Delaware			001-42194	99-6383052
(State or Other Jurisdiction of Incorporation)			(Commission File Number)	(IRS Employer Identification No.)
c/o Grayscale Investments Sponsors, LLC 290 Harbor Drive, 4th Floor
Stamford, Connecticut				06902
(Address of Principal Executive Offices)				(Zip Code)

Registrant’s Telephone Number, Including Area Code: 212 668-1427

N/A

(Former Name or Former Address, if Changed Since Last Report)

Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions:

	☐	Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425)
	☐	Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12)
	☐	Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b))
	☐	Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c))

Securities registered pursuant to Section 12(b) of the Act:

Title of each class		Trading Symbol(s)		Name of each exchange on which registered
Grayscale Bitcoin Mini Trust ETF Shares		BTC		NYSE Arca, Inc.

Indicate by check mark whether the registrant is an emerging growth company as defined in Rule 405 of the Securities Act of 1933 (§ 230.405 of this chapter) or Rule 12b-2 of the Securities Exchange Act of 1934 (§ 240.12b-2 of this chapter).

Emerging growth company ☒

If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act. ☐

Item 1.01. Entry into a Material Definitive Agreement.

Prime Broker Agreement

On October 3, 2025, Grayscale Investments Sponsors, LLC, the sponsor (the “Sponsor”), on behalf of itself and Grayscale Bitcoin Mini Trust ETF (the “Trust”), and Coinbase, Inc., the prime broker of the Trust (“Coinbase” or the “Prime Broker”), on behalf of itself and as agent for Coinbase Custody Trust Company, LLC (“Coinbase Custody” or the “Custodian”) and Coinbase Credit, Inc. (“Coinbase Credit” and, collectively with Coinbase and Coinbase Custody, the “Coinbase Entities”), entered into the Coinbase Prime Broker Agreement, which includes the Coinbase Custody Custodial Services Agreement attached thereto as Exhibit A (the “CSA”), the Coinbase Settlement and Transfer Agreement attached thereto as Exhibit B (the “STA”) and all other exhibits, addenda and supplements attached thereto (collectively with the CSA and STA, the “Prime Broker Agreement”) governing the Trust’s and the Sponsor’s use of the custodial and prime broker services provided by the Custodian and the Prime Broker. The Prime Broker Agreement establishes the rights and responsibilities of the Custodian, the Prime Broker, the Sponsor and the Trust with respect to the Trust’s Bitcoin which is held in accounts maintained and operated by the Custodian, as a fiduciary with respect to the Trust’s assets, and the Prime Broker (together with the Custodian, the “Custodial Entities”) on behalf of the Trust.

Coinbase Custody was party to the Previous Prime Broker Agreement (as defined in Item 1.02 below), and continues to serve as a custodian of the Trust. From and after October 3, 2025, all references to the “Prime Broker Agreement” in the Trust’s Annual Report on Form 10-K for the fiscal year ended December 31, 2024, as amended from time to time by the Trust’s filings with the SEC (the “Annual Report”), and descriptions related thereto are hereby deemed to refer to the Prime Broker Agreement as defined herein, rather than to the Previous Prime Broker Agreement, and are incorporated by reference herein.

The foregoing description is a summary, does not purport to be a complete description of the Prime Broker Agreement, and is qualified in its entirety by reference to the full text of the Prime Broker Agreement, a copy of which is filed as Exhibit 10.1 hereto and is incorporated by reference herein.

Fund Administration and Accounting Agreement

The Sponsor has engaged BNY Mellon Asset Servicing, a division of The Bank of New York Mellon, a New York corporation authorized to do a banking business (“BNY”), to provide the Trust with certain administrative and accounting services pursuant to the Fund Administration and Accounting Agreement with BNY, which became effective on October 9, 2025 (the “Fund Administration and Accounting Agreement”).

BNY was party to the Previous Fund Administration and Accounting Agreement (as defined in Item 1.02 below), and continues to provide the Trust with certain administrative and accounting services. From and after October 9, 2025, all references to the “Fund Administration and Accounting Agreement” in the Trust’s Annual Report and the descriptions related thereto are hereby deemed to refer to the Fund Administration and Accounting Agreement defined herein, rather than to the Previous Fund Administration and Accounting Agreement, and are incorporated by reference herein.

The foregoing description is a summary, does not purport to be a complete description of the Fund Administration and Accounting Agreement, and is qualified in its entirety by reference to the full text of the Fund Administration and Accounting Agreement, a copy of which is filed as Exhibit 10.2 hereto and is incorporated by reference herein.

Item 1.02. Termination of a Material Definitive Agreement.

Previous Prime Broker Agreement

In connection with the entry into the Prime Broker Agreement, the Sponsor and the Custodian agreed to terminate, as of October 3, 2025, the prime broker agreement, dated May 2, 2024, between the Trust, the Sponsor and the Prime Broker (the “Previous Prime Broker Agreement”).

Previous Fund Administration and Accounting Agreement

In connection with the entry into the Fund Administration and Accounting Agreement, the Sponsor and the Custodian agreed to terminate, as of October 9, 2025, the fund administration and accounting agreement, dated February 26, 2024, between the Trust and BNY (the “Previous Fund Administration and Accounting Agreement”).

Item 9.01 Financial Statements and Exhibits.

(d) Exhibits

Exhibit No.		Description
10.1		Prime Broker Agreement
10.2		Fund Administration and Accounting Agreement
104		Cover Page Interactive Data File (the cover page XBRL tags are embedded within the inline XBRL document)

SIGNATURES

Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned thereunto duly authorized.

			Grayscale Investments Sponsors, LLC, as Sponsor of Grayscale Bitcoin Mini Trust ETF
Date:	October 9, 2025	By:	/s/ Edward McGee
			Name: Edward McGee Title: Chief Financial Officer*

* The Registrant is a trust and the identified person signing this report is signing in their capacity as an authorized officer of Grayscale Investments Sponsors, LLC, the Sponsor of the Registrant.

FAQ

What new prime broker agreement did Grayscale Bitcoin Mini Trust ETF enter into?

Grayscale Bitcoin Mini Trust ETF entered a new Coinbase Prime Broker Agreement on October 3, 2025. It covers custodial and prime brokerage services for the Trust’s bitcoin through Coinbase, Coinbase Custody Trust Company, LLC, and Coinbase Credit, Inc., defining rights and responsibilities for all parties.

How does Coinbase Custody’s role change for Grayscale Bitcoin Mini Trust ETF (BTC)?

Coinbase Custody remains a custodian for the Trust under the new Prime Broker Agreement. It previously served under an earlier prime broker agreement, which was terminated as of October 3, 2025, and replaced by the updated contractual framework described in the current disclosure.

What services does BNY Mellon provide to Grayscale Bitcoin Mini Trust ETF?

BNY Mellon Asset Servicing provides administrative and accounting services under a Fund Administration and Accounting Agreement effective October 9, 2025. BNY previously provided similar services under a 2024 agreement, which was terminated and superseded by this new arrangement with the Trust.

Which prior agreements were terminated by Grayscale Bitcoin Mini Trust ETF?

The Trust terminated its previous prime broker agreement dated May 2, 2024, with Coinbase-related entities as of October 3, 2025. It also terminated the prior fund administration and accounting agreement with BNY dated February 26, 2024, effective October 9, 2025, replacing both with new contracts.

Does Grayscale Bitcoin Mini Trust ETF change key service providers in this 8-K?

The Trust keeps Coinbase-related entities as prime brokerage and custody providers and BNY Mellon as fund administrator. The main change is replacement of earlier 2024 agreements with updated Prime Broker and Fund Administration and Accounting Agreements, rather than switching to entirely new service firms.