Liberty Media estimates that the Exchange Ratio in the Redemption will be approximately 8.4 shares of New Sirius Common Stock per one share of Liberty SiriusXM Common Stock. This estimated Exchange Ratio is based on estimated net financial liabilities (excluding Liberty Media’s 3.75% Convertible Senior Notes due 2028, but including Liberty Media’s 2.75% Exchangeable Senior Debentures due 2049 and the Margin Loan) of the Liberty SiriusXM Group as of June 30, 2024 and estimates of transaction fees and expenses, financing fees, litigation-related liabilities and other corporate adjustments. Because the Exchange Ratio is not fixed and may vary, including due to (a) fluctuations in Liberty SiriusXM Group’s net financial liabilities, including its interest expense, transaction fees and expenses, financing fees and litigation-related liabilities, (b) changes to the trading prices of the shares of LSXMA or LSXMK between now and the Measurement Date, (c) any issuance of Liberty SiriusXM Equity Awards (as defined below) after the date of the Reorganization Agreement, (d) any issuance or repurchase by Liberty Media of shares of Liberty SiriusXM Common Stock (it being understood that any such issuances or repurchases require the prior written consent of Sirius XM Holdings under the Merger Agreement) and (e) any cancellation prior to the Measurement Date of Liberty SiriusXM Equity Awards issued prior to the Reorganization Agreement, the number of shares of New Sirius Common Stock to be received by holders of Liberty SiriusXM Common Stock in the Redemption may change from the estimated Exchange Ratio. Changes in the Exchange Ratio will impact the proportion of issued and outstanding New Sirius Common Stock following the completion of the Transactions represented by the shares of New Sirius Common Stock issued to former holders of Liberty SiriusXM Common Stock relative to former holders of Sirius XM Common Stock in the Transactions. The final Exchange Ratio, as determined in accordance with the Reorganization Agreement, will be rounded to the nearest ten-thousandth.

The Exchange Ratio will not change based on any changes in the trading prices of shares of LSXMB or Sirius XM Common Stock between now and the Measurement Date. Changes to the trading prices of the shares of LSXMA or LSXMK between now and the Measurement Date will not meaningfully

Yes. As more fully described in “Transaction Agreements — Reorganization Agreement — Conditions to Completion of the Contribution and the Redemption,” the completion of the Split-Off and related transactions are subject to (a) the satisfaction or, if permissible, waiver of the conditions set forth in the Merger Agreement (other than the conditions that the Split-Off has occurred and that the conditions to the Split-Off have been satisfied or, if permissible, waived), including, among others, the receipt (i) by Liberty Media of approval of the Split-Off Proposal by the affirmative vote of the holders of a majority of the aggregate voting power of the shares of LSXMA and LSXMB outstanding as of the record date, in each case, entitled to vote and that are present in person or by proxy at the Liberty Special Meeting, voting together as a separate class, and (ii) by Liberty Media and Sirius XM Holdings of the tax opinions described below, (b) the confirmation by the parties to the Merger Agreement that the completion of the Merger will occur subject only to the occurrence of the Split-Off Effective Time, and (c) the absence of any law, order or other legal restraint that has the effect of enjoining, restraining, preventing or prohibiting the consummation of the Contribution or Redemption. The foregoing conditions, other than the condition set forth in clause (c), may not be waived by Liberty Media, New Sirius or Sirius XM Holdings.

Yes. As more fully described in “Transaction Agreements — Merger Agreement — Conditions to Completion of the Merger,” the completion of the Merger depends on a number of conditions being satisfied or, if permissible, waived.

As more fully described in this proxy statement/notice/prospectus/information statement and in the Merger Agreement, during the pendency of the Merger Agreement, each of Liberty Media, New Sirius and Sirius XM Holdings has agreed to non-solicitation obligations with respect to third-party acquisition proposals (including provisions restricting their ability to provide confidential information to third parties) and has agreed to certain restrictions on it and its representatives’ ability to respond to any such proposals.

Yes. The Reorganization Agreement may be terminated and the Split-Off may be abandoned, at any time prior to the Split-Off Effective Time, (a) by Liberty Media for any reason if the Merger Agreement has been terminated in accordance with its terms or (b) by written agreement of Liberty Media, New Sirius and Sirius XM Holdings (through the Special Committee) if the Merger Agreement has not been terminated in accordance with its terms. If the Split-Off is not completed, then the Merger will not be completed.

Yes. Sirius XM Holdings (through the Special Committee) and Liberty Media may jointly agree to terminate the Merger Agreement at any time.

In the event the Merger Agreement is terminated, the Merger Agreement will become null and void (other than certain specified provisions as described in the next sentence) and none of Liberty Media, Sirius XM Holdings or New Sirius, or their respective directors, officers and affiliates, will have any liability under the Merger Agreement except that nothing will relieve any party from liability for fraud or any willful breach of the Merger Agreement. Certain designated provisions of the Merger Agreement, including, but not limited to, the payment of fees and expenses and confidentiality restrictions and, under certain circumstances, the payment of the termination fee described below, will survive the termination of the Merger Agreement. If the Merger Agreement is terminated, the Split-Off will not be completed.

The Merger Agreement provides that Liberty Media will be required to pay a termination fee to Sirius XM Holdings of $450 million in cash if Sirius XM Holdings (through the Special Committee) terminates the Merger Agreement as a result of the occurrence of a Liberty Adverse Recommendation Change.

No fractional shares of New Sirius Common Stock will be issued in connection with the Split-Off or the Merger. Instead, each holder of record of shares of Liberty SiriusXM Common Stock who would otherwise have received a fraction of a share of New Sirius Common Stock pursuant to the Redemption will receive cash in an amount of such holder’s pro rata share of the net proceeds from a sale by the Redemption Agent (as defined below) in the public market of the aggregate fractional shares of New Sirius Common Stock to be issued in the Redemption. No interest will be paid on any cash received in lieu of a fractional share. The receipt of cash in lieu of fractional shares will generally be taxable to the recipient stockholders. See “U.S. Federal Income Tax Consequences.” Because each applicable share of Sirius XM Common Stock issued and outstanding immediately prior to the Merger Effective Time is being converted into the right to receive one share of New Sirius Common Stock, no fractional shares are expected to arise as a result of the Merger.

Yes. The Reorganization Agreement provides for mutual indemnification obligations between Liberty Media and New Sirius, pursuant to which (a) New Sirius indemnifies Liberty Media for all losses and damages incurred by Liberty Media in connection with the liabilities that may exist relating to the businesses, assets and liabilities contributed to New Sirius in the Contribution in accordance with the Reorganization Agreement, together with liabilities resulting from any breach of any covenant by New Sirius in the Reorganization Agreement after the completion of the Split-Off, and (b) Liberty Media indemnifies New Sirius for all losses and damages incurred by New Sirius in connection with the liabilities that may exist relating to the businesses, assets and liabilities retained by Liberty Media following the Contribution in accordance with the Reorganization Agreement, together with liabilities resulting from any breach of any covenant by Liberty Media in the Reorganization Agreement. These indemnification obligations exclude any matters relating to taxes. For a description of the allocation of tax-related obligations, please see “Transaction Agreements — Tax Sharing Agreement” below.

We are delivering this proxy statement/notice/prospectus/information statement to holders of shares of LSXMA and LSXMB because it serves as a proxy statement being used by the board of directors of Liberty Media to solicit proxies of holders of LSXMA and LSXMB in connection with approval of the Split-Off Proposal and related matters. This document contains important information about the proposals being voted on at the Liberty Special Meeting, including the Split-Off Proposal. You should read it carefully and in its entirety. The enclosed materials allow you to have your shares of LSXMA or LSXMB voted by proxy without attending the Liberty Special Meeting. Your vote is important and we encourage you to submit your proxy as soon as possible.

You can find more information about Liberty Media and Sirius XM Holdings from various sources described in “Additional Information — Where You Can Find More Information.”

The Liberty Special Meeting will be held at [       ], Mountain time, on [           ]. The Liberty Special Meeting will be held via the Internet and will be a completely virtual meeting of the holders of LSXMA and LSXMB. You may attend the meeting, access the list of holders of LSXMA and LSXMB, submit questions and vote your shares electronically during the meeting via the Internet by visiting www.virtualshareholdermeeting.com/[           ]. To enter the Liberty Special Meeting, you will need the 16-digit control number that is printed in the box marked by the arrow on your proxy card. It is recommended that you log in at least 15 minutes before the meeting to ensure that you are logged in when the meeting starts. Online check-in will start shortly before the meeting on [           ].

The record date for the Liberty Special Meeting is 5:00 p.m., New York City time, on [           ].

No. While the approval of the Split-Off Proposal by the holders representing a majority of the aggregate voting power of the shares of LSXMA and LSXMB outstanding as of the record date, in each case, entitled to vote and that are present in person or by proxy at the Liberty Special Meeting, voting together as a separate class, is required to complete the Transactions, the adoption of the Merger Agreement and the approval of the Merger by the holders of LSXMA and LSXMB is not required to complete the Transactions and is not being sought by Liberty Media.

When considering the recommendation of the Liberty Media board of directors with respect to the Split-Off Proposal, holders of LSXMA and LSXMB should be aware that certain of Liberty Media’s directors and executive officers may be deemed to have interests in the Transactions that are different from, or in addition to, those of holders of Liberty SiriusXM Common Stock. These interests may present such persons with actual or potential conflicts of interest. The Liberty Media board of directors was aware of these interests during the deliberations of the merits of the Transactions, and in deciding to recommend that you vote for each of the Split-Off Proposal and the Adjournment Proposal.

In determining to approve the Transactions, the Liberty Media board of directors believes that the Transactions will benefit Liberty Media and its businesses and result in the creation of stockholder value because, among other things, the aggregate trading value of the New Sirius Common Stock that will be held by former holders of Liberty SiriusXM Common Stock following the completion of the Transactions is expected to exceed the aggregate trading value of the existing Liberty SiriusXM Common Stock. The Liberty Media board of directors determined that the Transactions are advisable and in the best interests of Liberty Media and its stockholders. The Liberty Media board of directors took into account a number of factors (none of which can be guaranteed to occur) when approving the Transactions, including the following:

The Liberty Media board of directors also considered a number of potential negative aspects and risks in approving the Transactions, including the following:

Liberty Media will cause the Redemption Agent to deliver or make available to all holders of certificated shares of Liberty SiriusXM Common Stock a letter of transmittal with which to surrender their certificated shares for the applicable number of shares of New Sirius Common Stock in book-entry form. Holders of certificated shares of Liberty SiriusXM Common Stock must surrender their stock certificates together with a duly executed letter of transmittal (and any other documentation required thereby) in order to receive their shares of New Sirius Common Stock in the Split-Off.

The Split-Off Proposal requires the affirmative vote of the holders of a majority of the aggregate voting power of the shares of LSXMA and LSXMB outstanding as of the record date, in each case, entitled to vote and that are present in person or by proxy at the Liberty Special Meeting, voting together as a separate class. Holders of other classes and series of Liberty Media stock, including LSXMK, are not being asked to vote, and are not entitled to vote, on the Split-Off Proposal because such vote is not required by Liberty Media’s certificate of incorporation, bylaws or the laws of the State of Delaware.

At the Liberty Special Meeting:

Under the terms of Liberty Media’s certificate of incorporation, the Liberty Media board of directors may, subject to the requisite approval of the holders of shares of LSXMA and LSXMB voting together as a separate class, redeem all of the outstanding shares of Liberty SiriusXM Common Stock for outstanding shares of New Sirius Common Stock. The approval of the Split-Off Proposal requires the affirmative vote of the holders of a majority of the aggregate voting power of the shares of LSXMA and LSXMB outstanding as of the record date, in each case, entitled to vote and that are present in person or by proxy at the Liberty Special Meeting, voting together as a separate class. Holders of shares of LSXMK are not being asked to vote, and are not entitled to vote, on the Split-Off Proposal because such vote is not required by Liberty Media’s certificate of incorporation, bylaws or the laws of the State of Delaware.

To ensure that a sufficient number of shares are present and entitled to vote at the Liberty Special Meeting on the Split-Off Proposal, Liberty Media may need to approve the adjournment of the Liberty Special Meeting from time to time to solicit additional proxies in favor of the Split-Off Proposal, if there are insufficient votes at the time of such adjournment to approve the Split-Off Proposal or if otherwise determined by the chairperson of the meeting to be necessary or appropriate. If no

If the Split-Off Proposal is not approved, neither the Split-Off nor the Merger will be completed, which means the existing shares of LSXMA, LSXMB and LSXMK will not be redeemed for shares of New Sirius Common Stock and the shares of Sirius XM Common Stock issued and outstanding immediately prior to the Merger Effective Time will not be converted into the right to receive the Merger Consideration.

After the Split-Off, shares of LSXMA, LSXMB and LSXMK will be delisted from the Nasdaq Global Select Market and will be deregistered under the Exchange Act.

After carefully reading and considering the information contained in or incorporated by reference into this proxy statement/notice/prospectus/information statement, you should submit your proxy before the Liberty Special Meeting in one of the following ways:

Yes. Any stockholder giving a proxy has the power to revoke it at any time before the proxy is voted at the Liberty Special Meeting. If you are a stockholder of record, you may revoke your proxy in any of the following ways:

The record date for the Liberty Special Meeting ([      ]) is earlier than the date of the Liberty Special Meeting and earlier than the date that the Transactions will be completed. If you sell or otherwise transfer your shares of LSXMA or LSXMB after the record date but before the date of the Liberty Special Meeting, you will retain your right to vote at the Liberty Special Meeting. However, you will not have the right to receive shares of New Sirius in the Split-Off. In order to receive shares of New Sirius in the Split-Off, you must hold your shares through the completion of the Split-Off.

Yes. You should carefully consider the risk factors set forth in the section entitled “Risk Factors” beginning on page 40. You should also read and carefully consider the risk factors of Liberty Media and Sirius XM Holdings contained in documents that are incorporated by reference into this proxy statement/notice/prospectus/information statement.

The preliminary voting results will be announced at the Liberty Special Meeting. In addition, within four business days of the Liberty Special Meeting, Liberty Media intends to file the final voting results with the SEC on a Current Report on Form 8-K.

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Broadridge Corporate Issuer Solutions, Inc. will have technicians ready to assist you with any individual technical difficulties you may have accessing the virtual meeting website. If you encounter any difficulties accessing the virtual meeting website during the check-in or meeting time for the Liberty Special Meeting, please call the technical support number that will be posted on the virtual meeting website log-in page at www.virtualshareholdermeeting.com/[           ].

After careful consideration of various factors, including those described in “The Proposed Transactions — Sirius XM Holdings’ Reasons for the Merger,” the Special Committee has unanimously (a) approved, and declared advisable and in the best interests of Sirius XM Holdings and its stockholders (other than Liberty Media and its subsidiaries), the Merger Agreement, including the Merger, each of the other transaction agreements to which Sirius XM Holdings is a party and the Transactions and (b) recommended that the board of directors of Sirius XM Holdings approve the

After careful consideration of the recommendation of the Special Committee and various factors including those described in “The Proposed Transactions — Sirius XM Holdings’ Reasons for the Merger,” the board of directors of Sirius XM Holdings unanimously (a) determined that the Merger Agreement and the transactions contemplated thereby, including the Merger, are in the best interests of Sirius XM Holdings and the Sirius XM Holdings stockholders (other than Liberty Media and its subsidiaries) and declared that the Merger Agreement is advisable, (b) approved the execution, delivery and performance by Sirius XM Holdings of the Merger Agreement and the transactions contemplated thereby, including the Merger and (c) recommended that the stockholders of Sirius XM Holdings (other than Liberty Media and its subsidiaries) adopt the Merger Agreement.

Yes. On December 11, 2023, Liberty Radio, which on such date owned of record a majority of the issued and outstanding shares of Sirius XM Common Stock and held a majority of the voting power of capital stock of Sirius XM Holdings, delivered the Sirius XM Stockholder Written Consent authorizing, adopting and approving the Merger Agreement and the transactions contemplated thereby, including the Merger. The Sirius XM Stockholder Written Consent became effective immediately following the execution and delivery of the Merger Agreement by all parties thereto. As a result, no further action by any stockholder of Sirius XM Holdings is required under applicable law or the Merger Agreement (or otherwise) to adopt the Merger Agreement or approve the transactions contemplated thereby, including the Merger.

New Sirius will cause the Exchange Agent to deliver or make available to all holders of certificated shares of Sirius XM Common Stock a letter of transmittal with which to surrender their certificated shares for the applicable number of shares of New Sirius Common Stock in book-entry form. Holders of certificated shares of Sirius XM Common Stock must surrender their stock certificates together with a duly executed letter of transmittal (and any other documentation required thereby) in order to receive their shares of New Sirius Common Stock in the Merger.

The Special Committee believes that the Transactions should provide benefits to Sirius XM Holdings and the holders of shares of Sirius XM Common Stock (other than Liberty Media, New Sirius and their respective subsidiaries), including:

Holders of Sirius XM Common Stock should be aware that certain of Sirius XM Holdings’ directors and executive officers may be deemed to have interests in the Transactions that are different from, or in addition to, those of holders of Sirius XM Common Stock. These interests may present such persons with actual or potential conflicts of interest. The Special Committee and the Sirius XM Holdings board of directors were aware of these interests during the deliberations of the merits of the Transactions.

The Sirius XM Holdings board of directors established the Special Committee and adopted resolutions stating that:

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After the Transactions, shares of Sirius XM Common Stock will be delisted from the Nasdaq Global Select Market and will be deregistered under the Exchange Act.

Following the Transactions, Liberty Media and New Sirius will operate independently, and neither will have any ownership interest in the other. In connection with the Split-Off, New Sirius and Liberty Media will enter into the Tax Sharing Agreement which will, among other things, govern Liberty Media’s and New Sirius’ respective rights, responsibilities and obligations with respect to certain taxes and tax benefits, the filing of tax returns, the control of tax audits and other tax matters. The terms of the Tax Sharing Agreement are further summarized in the section “Transaction Agreements — Tax Sharing Agreement” below.

If the Transactions are consummated, the New Sirius Common Stock is expected to be listed on the Nasdaq Global Select Market under Sirius XM Holdings’ current symbol, “SIRI.”

In connection with the appointments of the Liberty Media Designees and Sirius XM Holdings Designees discussed above, (a) three of the Sirius XM Holdings Designees will be designated as the initial Class I directors for a term expiring at the first annual meeting of stockholders of New Sirius held after the Merger Effective Time, (b) the remaining Sirius XM Holdings Designee and two Liberty Media Designees will be designated as the initial Class II directors for a term expiring at the second annual meeting of stockholders of New Sirius held after the Merger Effective Time, and (c) Mr. Maffei and the two remaining Liberty Media designees (who meet certain independence requirements) will be designated as the initial Class III directors for a term expiring at the third annual meeting of stockholders of New Sirius held after the Merger Effective Time. Pursuant to New Sirius’ amended and restated charter, the board of directors of New Sirius is authorized to assign members of the board of directors already in office to their respective class.

For a director to be deemed independent under the Nasdaq listing rules, New Sirius’ board of directors must affirmatively determine that the director has no direct or indirect material relationship with New Sirius. To assist New Sirius’ board of directors in determining which of its directors will qualify as independent, the nominating, environmental, social and governance committee of New Sirius’ board is expected to follow the Corporate Governance Rules of Nasdaq on the criteria for director independence.

The executive officers of New Sirius from and after the completion of the Merger will be the same persons who are the executive officers of Sirius XM Holdings immediately prior to the Merger.

Following the Transactions, New Sirius will not be deemed a “controlled company” under applicable exchange listing standards.

Upon completion of the Transactions, based on an estimated Exchange Ratio of 8.4, which assumes that as of June 30, 2024, there will be approximately 3,838.9 million shares of Sirius XM Common Stock outstanding, approximately 348.4 million shares of Liberty SiriusXM Common Stock outstanding and an estimated net liabilities share adjustment of 264.2 million shares of New Sirius Common Stock (which, based on the $4.23 Reference Price (as defined below) for shares of Sirius XM Common Stock, equates to approximately $1,118 million), former holders of Liberty SiriusXM Common Stock (in the aggregate) are expected to own New Sirius Common Stock representing approximately 81% of outstanding shares and former holders of Sirius XM Common Stock (in the aggregate, but other than Liberty Media and its subsidiaries) are expected to own New Sirius Common Stock representing approximately 19% of outstanding shares, in each case, immediately following the completion of the Merger. All of the foregoing percentages are approximations based on share information and net liabilities estimated as of such date and subject to change.

Liberty Media and Sirius XM Holdings are working to complete the Transactions as soon as practicable. We expect to complete the Transactions early in the third quarter of 2024. Neither Liberty Media nor Sirius XM Holdings can predict, however, the actual date on which the Transactions will be completed because they are subject to conditions beyond each company’s control.