BlackRock Portfolio Management LLC (YSS) unit reports 752,500-share Yellowstone Midco purchase

Rhea-AI Filing Summary

Funds and accounts managed by BlackRock subsidiaries, reported through BlackRock Portfolio Management LLC, acquired 752,500 shares of Yellowstone Midco Holdings II, LLC common stock on January 30, 2026 at $34 per share. After this purchase, 17,846,934 shares of Yellowstone Midco common stock are reported as indirectly held.

These shares are held across multiple advised funds and accounts managed by various BlackRock entities. BlackRock Portfolio Management LLC, the advised funds and accounts, and their related managers expressly disclaim beneficial ownership of these shares except to the extent of their pecuniary interest, and state that inclusion in this report is not an admission of beneficial ownership.

SEC Form 4

FORM 4

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

STATEMENT OF CHANGES IN BENEFICIAL OWNERSHIP

Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934
or Section 30(h) of the Investment Company Act of 1940

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Check this box if no longer subject to Section 16. Form 4 or Form 5 obligations may continue. See Instruction 1(b).

Check this box to indicate that a transaction was made pursuant to a contract, instruction or written plan for the purchase or sale of equity securities of the issuer that is intended to satisfy the affirmative defense conditions of Rule 10b5-1(c). See Instruction 10.

1. Name and Address of Reporting Person^*

BlackRock Portfolio Management LLC

(Last) (First) (Middle)

50 HUDSON YARDS

(Street)

NEW YORK NY 10001

(City) (State) (Zip)

2. Issuer Name and Ticker or Trading Symbol
Yellowstone Midco Holdings II, LLC [ YSS ]

5. Relationship of Reporting Person(s) to Issuer
(Check all applicable)

	Director	X	10% Owner
	Officer (give title below)		Other (specify below)

3. Date of Earliest Transaction (Month/Day/Year)
01/30/2026

4. If Amendment, Date of Original Filed (Month/Day/Year)

6. Individual or Joint/Group Filing (Check Applicable Line)

X	Form filed by One Reporting Person
	Form filed by More than One Reporting Person

Table I - Non-Derivative Securities Acquired, Disposed of, or Beneficially Owned
1. Title of Security (Instr. 3)	2. Transaction Date (Month/Day/Year)	2A. Deemed Execution Date, if any (Month/Day/Year)	3. Transaction Code (Instr. 8)		4. Securities Acquired (A) or Disposed Of (D) (Instr. 3, 4 and 5)			5. Amount of Securities Beneficially Owned Following Reported Transaction(s) (Instr. 3 and 4)	6. Ownership Form: Direct (D) or Indirect (I) (Instr. 4)	7. Nature of Indirect Beneficial Ownership (Instr. 4)
			Code	V	Amount	(A) or (D)	Price
Common Stock	01/30/2026		P		752,500	A	$34	17,846,934	I	See footnote(1)(2)(3)

Table II - Derivative Securities Acquired, Disposed of, or Beneficially Owned (e.g., puts, calls, warrants, options, convertible securities)
1. Title of Derivative Security (Instr. 3)	2. Conversion or Exercise Price of Derivative Security	3. Transaction Date (Month/Day/Year)	3A. Deemed Execution Date, if any (Month/Day/Year)	4. Transaction Code (Instr. 8)		5. Number of Derivative Securities Acquired (A) or Disposed of (D) (Instr. 3, 4 and 5)		6. Date Exercisable and Expiration Date (Month/Day/Year)		7. Title and Amount of Securities Underlying Derivative Security (Instr. 3 and 4)		8. Price of Derivative Security (Instr. 5)	9. Number of derivative Securities Beneficially Owned Following Reported Transaction(s) (Instr. 4)	10. Ownership Form: Direct (D) or Indirect (I) (Instr. 4)	11. Nature of Indirect Beneficial Ownership (Instr. 4)
				Code	V	(A)	(D)	Date Exercisable	Expiration Date	Title	Amount or Number of Shares

Explanation of Responses:

1. Represents shares of the Issuer's common stock held by the following funds and accounts under management by certain subsidiaries of BlackRock, Inc.: BlackRock Private Equity Co-Investments, 2021 Aggregator Cayman Ltd., BlackRock Growth Equity Fund Master Cayman Aggregator Ltd., BR POF IV CAYMAN MASTER FUND, L.P., BlackRock Private Opportunities Fund IV, L.P., BlackRock Private Opportunities Fund IV Master SCSp, TSCL Private Markets Cayman Fund Ltd., 1885 Private Opportunities Cayman Fund, Ltd., Heathrow Forest Opportunities Fund, L.P., Lincoln Pension Private Equity BR, L.P., NHRS Private Opportunities Fund, L.P., NDSIB Private Opportunities Fund Cayman Ltd., Mutual of Omaha OF Cayman, Ltd., BlackRock ERI Private Opportunities Master SCSp, Sullivan Way POF Cayman, Ltd, Total Alternatives Fund - Private Equity (B) LP, Total Alternatives Fund - Private Equity LP, 1824 Private Equity Fund, L.P., Tango Capital Opportunities Fund, L.P., BlackRock Private Investments Fund,

2. (Continued from footnote 1) OV Private Opportunities Cayman, Ltd., SONJ Opportunities Cayman, Ltd., Red River Direct Investment Fund III, L.P., MB BlackRock Holdings Cayman Ltd. and certain other funds and accounts managed by BlackRock Financial Management, Inc., BlackRock Institutional Trust Company, National Association, BlackRock Investment Management (UK) Limited and BlackRock Investment Management, LLC (collectively, the "Advised Funds and Accounts"). Each of BlackRock Portfolio Management LLC, the Advised Funds and Accounts and their respective direct or indirect managers, general partners and portfolio managers who share voting and investment power over the shares held by the Advised Funds and Accounts expressly disclaim beneficial ownership of the shares of common stock held by the Advised Funds and Accounts, except to the extent of their pecuniary interest therein,

3. (Continued from footnote 2) and the inclusion of these shares in this report shall not be deemed an admission of beneficial ownership of the reported shares for purposes of Section 16 or for any other purposes.

Remarks:

In accordance with SEC Release No. 34-39538 (January 12, 1998), BlackRock Portfolio Management LLC is reporting Issuer securities beneficially owned, or deemed to be beneficially owned, by certain business units (collectively, the "Reporting Business Units") of BlackRock, Inc. and its subsidiaries and affiliates. This filing does not include Issuer securities, if any, beneficially owned by other business units whose beneficial ownership of securities is disaggregated from that of the Reporting Business Units in accordance with such release.

	BlackRock Portfolio Management LLC, By: /s/ David Maryles, Authorized Signatory	02/03/2026
	** Signature of Reporting Person	Date
Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly.
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FAQ

What insider transaction did BlackRock-related funds report in YSS common stock?

Funds and accounts managed by BlackRock subsidiaries reported buying 752,500 shares of Yellowstone Midco Holdings II, LLC (YSS) common stock. The purchase occurred on January 30, 2026 at $34 per share, increasing the indirectly reported position to 17,846,934 shares.

Who is the reporting person on this YSS Form 4 filing?

The reporting person is BlackRock Portfolio Management LLC, identified as a 10% owner of Yellowstone Midco Holdings II, LLC. It reports securities beneficially owned or deemed beneficially owned by certain BlackRock business units, rather than indicating a personal transaction by an individual executive.

How many YSS shares are indirectly held after the reported transaction?

Following the January 30, 2026 purchase, 17,846,934 shares of Yellowstone Midco Holdings II, LLC common stock are reported as indirectly held. These shares are spread across numerous advised funds and accounts managed by BlackRock-affiliated entities, as detailed in the footnotes.

At what price were the newly acquired YSS shares purchased?

The 752,500 Yellowstone Midco Holdings II, LLC common shares were purchased at $34 per share. This price applies to the non-derivative transaction reported on January 30, 2026 under transaction code “P,” which indicates an open-market or private purchase of stock.

Do BlackRock entities claim full beneficial ownership of the reported YSS shares?

No. BlackRock Portfolio Management LLC, the advised funds and accounts, and related managers expressly disclaim beneficial ownership of the reported Yellowstone Midco shares, except to the extent of their pecuniary interest. They also state that including these shares is not an admission of beneficial ownership.

Which funds and accounts hold the YSS shares reported on this Form 4?

The shares are held by a wide range of BlackRock-managed vehicles, including BlackRock Private Equity Co-Investments, various Cayman and limited partnership funds, and other advised funds and accounts. The footnotes list these entities collectively as the “Advised Funds and Accounts.”