Welcome to our dedicated page for SilverBox SEC filings (Ticker: SBXD), a comprehensive resource for investors and traders seeking official regulatory documents including 10-K annual reports, 10-Q quarterly earnings, 8-K material events, and insider trading forms.
SilverBox Corp IV (SBXD) files a range of documents with the U.S. Securities and Exchange Commission (SEC) that detail its activities as a New York Stock Exchange-listed special purpose acquisition company (SPAC). On this page, investors can review SBXD’s SEC filings, including current reports on Form 8-K that describe material events connected to its proposed business combination with Parataxis Holdings LLC and Parataxis Holdings Inc. (Pubco).
The company’s Form 8-K filings outline key steps in the transaction process, such as the execution and amendment of the Business Combination Agreement, the filing of the Registration Statement on Form S-4 that includes a preliminary proxy statement and prospectus, and changes to preferred equity subscription agreements related to Bitcoin purchases by Parataxis Holdings. Other 8-K reports address governance matters, including director resignations and appointments and committee assignments.
For a SPAC like SilverBox Corp IV, investors often focus on filings that explain the structure and consideration of the business combination, the treatment of public shares and warrants, and the conditions that must be satisfied before closing. The Registration Statement on Form S-4, referenced repeatedly in SBXD’s 8-Ks, is central to understanding the proposed mergers that will result in SilverBox Corp IV and Parataxis Holdings LLC becoming wholly owned subsidiaries of Pubco.
Stock Titan’s platform provides access to these SEC filings with AI-powered summaries that help explain complex transaction terms and risk disclosures in clearer language. Users can quickly see the main points of lengthy documents such as Form 8-Ks and the S-4 Registration Statement, while still being able to open the full text for detailed review. Real-time updates from EDGAR ensure that new filings, including any future proxy materials or additional current reports, are available as soon as they are posted, supporting investors who monitor SBXD’s progress toward its initial business combination.
SilverBox Corp IV reported an amendment to previously disclosed Preferred Equity Subscription Agreements tied to its proposed business combination with Parataxis. Earlier, Parataxis agreed to sell an aggregate of 3,100,000 preferred equity units at $10.00 per unit for a total of $31,000,000 in a private placement.
Effective October 31, 2025, the parties removed restrictions that had barred pledging the Bitcoin purchased with those proceeds and now permit that Bitcoin to be used as collateral or other credit support to secure indebtedness or obligations under lending or other financing arrangements. The filing also notes that a Registration Statement on Form S-4 (No. 333-289994) including a preliminary proxy statement/prospectus has been filed for the proposed business combination.
SilverBox Corp IV reports that Parataxis Holdings Inc. and Parataxis Holdings LLC have filed a Form S-4 registration statement for their previously announced business combination with SilverBox. The S-4 includes a preliminary proxy statement for SilverBox shareholders and a prospectus for Pubco, which will be mailed in definitive form to shareholders as of a future record date to vote on the transaction. The communication stresses that it is not an offer or solicitation and that any securities offering will be made only by a prospectus meeting Securities Act requirements.
The filing outlines extensive forward-looking risk factors, including the possibility the deal may not close, high redemption levels, listing uncertainties for Pubco, costs of becoming public, and Pubco’s planned Bitcoin-focused strategy. It notes that Pubco’s results and stock price may be highly sensitive to Bitcoin prices, regulatory treatment of crypto assets, potential dilution from warrants and equity financing, and legal, regulatory and geopolitical risks, including those related to South Korea and a KOSDAQ-listed investment.
Highbridge Capital Management, LLC filed a Schedule 13G reporting ownership of 1,228,800 Class A Ordinary Shares of SilverBox Corp IV (CUSIP G81354105), representing 5.9% of the Class A shares outstanding based on 20,455,000 shares as of May 13, 2025. The reported amount includes 280,000 Class A shares issuable upon conversion of Class B ordinary shares held by Highbridge Funds. The filing states the securities are held in the ordinary course of business and not for the purpose of changing or influencing control of the issuer.
The report cites Highbridge's address in New York and identifies it as a Delaware investment adviser filing on behalf of the Highbridge Funds.
Polar Asset Management Partners Inc. reports beneficial ownership of 1,480,000 Class A ordinary shares of Silverbox Corp IV, representing 7.2% of the class. The filing is a Schedule 13G/A amendment and shows Polar holds sole voting and sole dispositive power over the shares.
The filing states Polar serves as investment adviser to Polar Multi-Strategy Master Fund and that the securities are held in the ordinary course of business and not for the purpose of changing or influencing control of the issuer. The disclosure provides clarity on a material passive stake above 5% in Silverbox Corp IV.
SilverBox Corp IV disclosed that AQR Capital Management, LLC, AQR Capital Management Holdings, LLC and AQR Arbitrage, LLC collectively beneficially own 1,347,002 Class A ordinary shares, equal to 6.59% of the class. The reporting parties state they possess shared voting and shared dispositive power over these shares and report no sole voting or sole dispositive power, indicating coordinated institutional ownership rather than unilateral control.
The filers certify the securities are held in the ordinary course of business and not for the purpose of changing or influencing control of the issuer. The disclosure therefore documents a material passive stake by a large investment adviser group without signaling an active governance or control intent.
SilverBox Corp IV is reported as being beneficially owned, in part, by The Goldman Sachs Group, Inc. and its subsidiary Goldman Sachs & Co. LLC. The filers disclose shared voting and dispositive power over 1,606,929 Class A ordinary shares, representing 7.9% of the class. The schedule is a joint filing by the parent and its broker/dealer subsidiary and includes an agreement authorizing joint amendments and an exhibit identifying the subsidiary that holds the reported position. The filers state the securities are held in the ordinary course of business and not for the purpose of changing control.
Healthcare of Ontario Pension Plan Trust Fund (HOOPP) reports beneficial ownership of 100,000 Class A ordinary shares of SilverBox Corp IV, representing 0.5% of the outstanding Class A shares based on 20,455,000 shares reported by the issuer. The position consists of 99,998 Class A shares plus 2 Class A shares held in units that include one-third of a redeemable warrant; whole warrants are exercisable at $11.50 per share. HOOPP states these securities are held in the ordinary course of business and were not acquired to influence control. HOOPP is a pension plan trust formed under Ontario law and reports sole voting and dispositive power over the 100,000 shares.
Barclays PLC reports beneficial ownership of 970,927 shares of SilverBox Corp IV common stock, representing 4.74% of the class. The filing states Barclays has sole voting and sole dispositive power over these shares, meaning it controls how the shares are voted and disposed. The schedule identifies Barclays Bank PLC as the subsidiary that acquired the securities and classifies the filer as a holding company. The filer certifies the shares were acquired and are held in the ordinary course of business and not to influence control of the issuer.
SilverBox Corp IV (SBXD) is a blank-check company that held $208,952,965 in a trust and reported total assets of $209,469,723 at June 30, 2025. The company generated $4.30 million of interest on trust investments for the six months and reported $3.39 million net income for the same period, while operating costs were $904,943 for six months. Cash outside the trust was $279,366 with working capital of $454,784, and Class A shares subject to redemption were recorded at a redemption value of $208,952,965.
The balance sheet shows material deferred obligations, including a $10.3 million deferred underwriting fee and $975,661 of deferred legal fees. Management disclosed substantial doubt about the company’s ability to continue as a going concern within one year absent additional financing. In subsequent events, on August 6, 2025 the company entered a business combination agreement with Parataxis and agreed to engage Santander US Capital Markets for advisory services with fees up to $10.3 million.