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): ~~September~~October 253, 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.

OnPrime ~~September~~Broker 25, 2025, Grayscale Investments Sponsors, LLC, the sponsor (the “Sponsor”) of Grayscale Bitcoin Mini Trust ETF (the “Trust”), and Anchorage Digital Bank N.A. (“Anchorage Digital”), a national trust bank chartered by the Office of the Comptroller of the Currency, entered into a certain Second Amendment to Master Custody Service Agreement (the “Second Amendment”), which provides that the Trust is added as a party to a certain Master Custody Service Agreement, dated as of August 8, 2025 (and together with the Second Amendment, the “Anchorage Digital Custodian Agreement” or the “Agreement”).

~~Pursuant~~On toOctober 3, 2025, Grayscale Investments Sponsors, LLC, the ~~Anchorage~~sponsor ~~Digital~~(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, ~~Anchorage~~which ~~Digital~~includes ~~will~~the ~~provide~~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 ~~related~~provided toby ~~custody~~the Custodian and ~~safekeeping~~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 ~~holdings~~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.

~~The~~Coinbase ~~Sponsor~~Custody ~~expects~~was toparty ~~utilize Anchorage Digital’s services~~ to ~~custody a portion of~~ the ~~Trust’s~~Previous ~~Bitcoin.~~Prime ~~The~~Broker ~~Trust’s~~Agreement ~~existing~~(as ~~custody~~defined ~~arrangement~~in ~~with~~Item ~~Coinbase~~1.02 ~~Trust Company~~below), ~~LLC~~and ~~(“Coinbase”)~~continues isto ~~unaffected~~serve byas ~~the~~a ~~Trust’s~~custodian ~~entry~~of ~~into~~ the ~~Agreement, and Coinbase remains the~~ Trust’s. ~~primary~~From ~~custodian.~~and ~~The~~after ~~Sponsor~~October ~~shall~~3, ~~in its sole discretion~~2025, ~~determine~~all ~~the~~references ~~amounts~~to ~~held at either custodian as permitted by~~ the ~~Trust~~“Prime Broker Agreement.” Atin the ~~current time, the Sponsor has not determined the amount of the~~ Trust’s ~~Bitcoin~~Annual itReport ~~will~~on ~~move~~Form to10-K ~~Anchorage~~for ~~Digital.~~the ~~The~~fiscal ~~addition~~year ofended ~~Anchorage~~December ~~Digital~~31, ~~reflects~~2024, ~~the~~as ~~Sponsor’s~~amended ~~ongoing~~from ~~risk~~time ~~management~~to ~~approach~~time asby ~~part of~~ the Trust’s ~~growing~~filings ~~size.~~with ~~References to “~~the ~~Custodian”~~SEC ~~in our annual report on Form 10-K for~~ (the ~~fiscal~~“Annual ~~period~~Report”), ~~ended~~and ~~December~~descriptions ~~31,~~related ~~2024~~thereto ~~will~~are behereby deemed to refer to ~~Coinbase,~~the ~~Anchorage~~Prime ~~Digital~~Broker ~~and/or~~Agreement ~~other~~as ~~Custodians~~defined herein, ~~collectively~~rather orthan into ~~their~~the ~~individual~~Previous ~~capacities~~Prime Broker Agreement, asand ~~the~~are ~~context~~incorporated ~~may~~by ~~require~~reference herein.

~~Under~~The ~~the~~foregoing ~~Anchorage~~description ~~Digital~~is ~~Custodian~~a ~~Agreement~~summary, ~~Anchorage~~does ~~Digital~~not ispurport ~~required~~ to ~~keep~~be ~~all of the private keys associated with the Trust’s Bitcoin held at Anchorage Digital in cold storage. Cold storage is~~ a ~~safeguarding~~complete ~~method~~description byof ~~which~~ the ~~private~~Prime ~~key(s)~~Broker ~~corresponding~~Agreement, toand ~~Bitcoin~~ is ~~(are)~~qualified ~~generated and stored~~ in anits ~~offline~~entirety ~~manner.~~by ~~Private~~reference ~~keys are generated in offline computers or devices that are not connected~~ to the ~~internet~~full sotext ~~that~~of ~~they are more resistant to being hacked. By contrast, in hot storage,~~ the ~~private~~Prime ~~keys~~Broker ~~are held online~~Agreement, ~~where~~a ~~they~~copy ~~are~~of ~~more~~which ~~accessible,~~is ~~leading~~filed toas ~~more~~Exhibit ~~efficient~~10.1 ~~transfers,~~hereto ~~though~~and ~~they~~is ~~are~~incorporated ~~potentially~~by ~~more~~reference ~~vulnerable to being hacked~~herein.

InFund ~~the~~Administration ~~event of a fork of the Bitcoin blockchain, the Anchorage Digital Custodian Agreement provides that Anchorage Digital may temporarily suspend services,~~ and ~~may,~~Accounting in its sole discretion, determine whether or not to support (or cease supporting) either branch of the forked protocol entirely, provided that Anchorage shall use commercially reasonable efforts to avoid ceasing to support both branches of such forked protocol.Agreement

The ~~Anchorage~~Sponsor ~~Digital~~has ~~Custodian~~engaged ~~Agreement~~BNY ~~requires~~Mellon ~~the~~Asset ~~Trust~~Servicing, toa ~~indemnify~~division ~~Anchorage~~of ~~Digital,~~The ~~its~~Bank ~~affiliates,~~of ~~and~~New ~~their~~York ~~respective officers~~Mellon, ~~directors,~~a ~~agents,~~New ~~employees~~York ~~and~~corporation ~~representatives~~authorized ~~against~~to ~~certain~~do ~~losses~~a ~~arising~~banking ~~from~~business or(“BNY”), ~~related~~ to provide the Trust’s ~~material~~with ~~breach~~certain ofadministrative ~~the~~and ~~Anchorage~~accounting ~~Digital~~services ~~Custodian~~pursuant ~~Agreement,~~to ~~among~~the ~~other~~Fund ~~things,~~Administration ~~except~~and ~~where~~Accounting aAgreement ~~claim~~with ~~was~~BNY, ~~caused~~which bybecame ~~certain~~effective ~~acts~~on ofOctober ~~Anchorage~~9, ~~Digital.~~2025 ~~The~~(the ~~Anchorage~~“Fund ~~Digital~~Administration ~~Custodian Agreement also requires Anchorage Digital to maintain insurance policies~~ and ~~coverage~~Accounting Agreement”).

~~The~~BNY ~~foregoing~~was ~~description~~party ofto the ~~Anchorage~~Previous ~~Digital~~Fund ~~Custodian~~Administration and Accounting Agreement ~~does~~(as ~~not~~defined ~~purport~~in Item 1.02 below), and continues to beprovide ~~complete~~the Trust with certain administrative and isaccounting ~~qualified~~services. inFrom ~~its~~and ~~entirety~~after byOctober ~~reference~~9, 2025, all references to the ~~full~~“Fund ~~text~~Administration ofand Accounting Agreement” in the ~~Anchorage~~Trust’s ~~Digital~~Annual ~~Custodian~~Report and the descriptions related thereto are hereby deemed to refer to the Fund Administration and Accounting Agreement ~~filed~~defined ~~with~~herein, ~~this~~rather ~~Current~~than ~~Report~~to onthe ~~Form~~Previous ~~8-K~~Fund asAdministration ~~Exhibit~~and ~~10.1~~Accounting Agreement, and ~~Exhibit~~are 10incorporated by reference herein.2.

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		~~Master~~Prime ~~Custody~~Broker ~~Service~~ Agreement~~, dated August 8, 2025, between the Trust and Anchorage Digital Bank N.A.~~
10.2		~~Second~~Fund ~~Amendment~~Administration ~~to Master Custody Service Agreement, dated September 25, 2025, between the Trust~~ and ~~Anchorage~~Accounting ~~Digital Bank N.A.~~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:	~~September~~October 269, 2025	By:	/s/ Edward McGee
			Name: Edward McGeeTitle: 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.

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