S-1: MIAX Selling Stockholders Offer 6.75M Shares in Secondary Offering

Selling stockholders of Miami International Holdings, Inc. are offering up to 6.75 million common shares, with the company receiving no proceeds from the sale.

Summary

• Selling stockholders are offering up to 6,750,000 shares of common stock, with an option for underwriters to purchase an additional 1,012,500 shares.
• The company will not receive any proceeds from this secondary offering; all proceeds will go to the selling stockholders.
• On December 8, 2025, the closing price of the company's common stock was $45.56 per share.
• For the nine months ended September 30, 2025, revenues less cost of revenues increased to $306.0 million, up 57.8% from $193.9 million in the same period of 2024.
• The company reported a net loss of $(99.973) million for the nine months ended September 30, 2025, compared to a net income of $99.095 million for the same period in 2024.
• Adjusted EBITDA for the nine months ended September 30, 2025, was $136.9 million, a 159.6% increase from $52.7 million in the same period of 2024.
• Options market average daily volume (ADV) on MIAX Exchanges increased 40.4% to 9.0 million contracts for the nine months ended September 30, 2025, compared to 6.4 million in 2024.
• U.S. Equities market share on MIAX Pearl Equities decreased to 1.1% for the nine months ended September 30, 2025, from 1.7% in the same period of 2024.
• Futures agricultural products ADV increased 14.1% to 14,633 contracts for the nine months ended September 30, 2025, compared to 12,828 in 2024.
• The company completed its Initial Public Offering (IPO) on August 15, 2025, issuing 17,250,000 shares at $23.00 per share, raising $396.8 million in gross proceeds for the company.
• Proceeds from the IPO were used to fully repay $140.0 million in outstanding borrowings under the 2029 Senior Secured Term Loan, incurring a $107.7 million loss on debt extinguishment.
• The TISE Acquisition was completed on June 5, 2025, providing access to European and UK markets, and resulted in $18.0 million of goodwill and $76.0 million of intangible assets.
• MIAXdx's SEF license went dormant in July 2025, and it delisted all physically settled products as of July 24, 2024, now focusing on cash-settled binary options on Bitcoin.
• The company recognized a $2.1 million loss on the sale of the second tranche of 125 million Pyth tokens in Q2 2025, compared to a $52.6 million gain on the first tranche in Q2 2024.

Sentiment

Score: 4

Explanation: The company shows strong operational growth in its core Options segment and strategic expansion through acquisitions and new product development. However, the significant net loss for the nine months ended September 30, 2025, primarily due to a large debt extinguishment loss, and declines in the Equities and MIAXdx segments, along with ongoing regulatory uncertainties, temper the overall positive sentiment.

Positives

• Strong growth in Options market: ADV increased 40.4% to 9.0 million contracts and market share rose to 16.7% for the nine months ended September 30, 2025.
• Significant increase in revenues less cost of revenues by 57.8% to $306.0 million for 9M 2025, driven by Options segment performance.
• Adjusted EBITDA saw substantial growth, increasing 159.6% to $136.9 million for 9M 2025, indicating improved operational profitability excluding certain non-recurring items.
• Successful completion of IPO on August 15, 2025, raising $396.8 million in gross proceeds for the company, which was used to repay significant debt.
• Strategic acquisition of TISEG in June 2025 expands international presence into European and UK markets, adding new listing services.
• Launch of MIAX Sapphire electronic exchange in August 2024 and a physical trading floor in Miami in September 2025, enhancing options market access.
• Development of new proprietary products, including Bloomberg Products (B500 Index and B100Q Index futures/options) with exclusive 10-year licenses, expected to launch in H1 2026.
• MIAX Futures Onyx trading platform launched in June 2025, migrating Hard Red Spring Wheat futures and planning for additional financial futures in H1 2026.
• BSX is a global leader in Insurance Linked Securities (ILS) listings, representing approximately 92.7% of global issuance as of September 30, 2025.
• TISE's Qualified Investor Bond Market (QIBM) is a leading market in Europe for high yield bonds and private equity debt, with growing listings.

Negatives

• Reported a net loss of $(99.973) million for the nine months ended September 30, 2025, a significant decline from net income of $99.095 million in the prior year period.
• Incurred a substantial loss on debt extinguishment of $107.7 million in 9M 2025 due to the repayment of the 2029 Senior Secured Term Loan using IPO proceeds.
• U.S. Equities market share decreased to 1.1% for 9M 2025 from 1.7% in 9M 2024, and Equities capture remained negative, indicating liquidity payments still exceeded transaction revenues.
• Futures agricultural products ADV decreased 34.5% for the three months ended September 30, 2025, attributed to participant migration to the new Onyx platform and lower volatility.
• MIAXdx's SEF license went dormant in July 2025, and total volume on MIAXdx decreased 99.9% for 9M 2025, reflecting a transition away from physically settled products.
• Realized loss of $2.1 million on the sale of the second tranche of Pyth tokens in Q2 2025, following an unrealized loss of $39.0 million on derivative assets for 9M 2025.
• The company's cost structure is largely fixed, posing a risk to profitability if revenues decline and costs cannot be adjusted timely.
• MIAXdx is subject to CFTC inquiries related to activities prior to its acquisition by the company, which could result in substantial costs and reputational harm.

Risks

• A significant portion of operating revenues is generated by transaction and clearing-based business, making the company vulnerable to decreases in trading volume or shifts to lower revenue products.
• Global economic, political, and financial market events or conditions, including recessions, inflation, and geopolitical conflicts, may negatively impact the business.
• Failure to maintain order flow from providers following the IPO and this offering could negatively affect results of operations.
• Revenues from market data fees and access fees on MIAX Exchanges may be reduced due to declines in market share, trading volumes, or regulatory changes, such as challenges to CAT funding models.
• Intense competition from other exchanges, OTC markets, clearing organizations, and technology firms could adversely affect market share and revenues.
• Reliance on index providers for proprietary products means failure to maintain quality/integrity of indexes or changes in customer preferences could impact revenues.
• Dependence on senior management and highly skilled employees, with significant losses potentially harming the business.
• Certain exchanges and clearing houses have limited operating history, making it difficult to evaluate business and prospects.
• Financial or other problems experienced by third parties (customers, clearing houses, settlement banks) could have an adverse effect on the business, including credit and liquidity risks.
• Exposure to risks related to defaults by clearing members and liquidity risks in operating clearing houses, particularly if a significant number of clearing members reduce open interest or default.
• Settlement bank failures could pose both credit and liquidity risks to MIAX Futures and MIAXdx clearing houses.
• Crypto-asset custodial solutions are subject to risks of theft, security breaches, system failures, and legal uncertainty regarding custodial arrangements.
• Dorman Trading (FCM) is subject to margin funding requirements on short notice, counterparty credit risk, and risk of default by financial institutions holding funds.
• Risk management policies and procedures may not be fully effective in mitigating all types of risk, including unidentified or unanticipated risks.
• Failure to successfully offer new services or product offerings, including Bloomberg Products or crypto-related products, could result in missed market opportunities and unrecovered costs.
• Need for significant investments in operations and technology to maintain and grow, with potential need for additional funds that may not be readily available.
• Acquisitions and strategic alliances involve risks and may not produce anticipated cost savings, growth opportunities, or synergies.
• Inability to keep up with rapid technological changes, significant or recurring systems failures, or capacity constraints could harm reputation and business.
• Dependence on third-party providers for key components and services, with interruptions potentially causing significant disruptions.
• Use of open-source software code may subject proprietary software to general release or require re-engineering.
• Software errors, bugs, or vulnerabilities in products, platforms, and internal systems could adversely affect the business.
• Covenant restrictions in future debt may limit operations and impact ability to make payments to investors.
• Future sales and issuances of common stock or rights to purchase common stock could result in additional dilution and cause stock price decline.
• Impairments of goodwill, other intangible assets, or investments could negatively impact future operating results.
• Pyth tokens are based on a highly volatile asset, and price fluctuations may affect financial results.
• Subject to comprehensive regulation by SEC, CFTC, NFA, BMA, and GFSC, which can negatively impact ability to implement changes or expand products/services.
• Regulatory hurdles to launching new products, including crypto-related products, and potential for regulatory scrutiny, fines, or penalties.
• Changes to legislative or regulatory environment may impose new or unanticipated burdens on exchanges or clearing houses.
• Self-regulatory obligations of exchanges may create conflicts of interest.
• Compliance with data privacy and data protection laws may result in greater costs.
• Misconduct or errors by employees or agents could harm business and reputation.
• Litigation risks, regulatory compliance risks, and other liabilities, including the ongoing Nasdaq matter.
• Inability to protect, maintain, defend, or enforce intellectual property rights could adversely affect business.
• Infringement on intellectual property rights of others could result in litigation.
• Market price of common stock is subject to fluctuations and may not reflect long-term value, potentially leading to securities litigation.
• Ownership and voting limitations in amended and restated certificate of incorporation may impede change of control transactions.
• Certain provisions in corporate documents may make acquisition of the company more difficult.
• Board of directors authorized to issue preferred stock without stockholder approval, potentially affecting common stock value.
• No current intention to pay dividends on common stock.
• Significant additional costs and expenses associated with being a public company, particularly after ceasing to be an emerging growth company.
• Reduced disclosure requirements as an emerging growth company may make common stock less attractive to investors.
• Climate change and the transition to renewable energy pose operational, commercial, reputational, and regulatory risks.
• Global health crises, pandemics, and other health risks could negatively affect the business.
• Failure to implement and maintain effective internal controls over financial reporting could lead to loss of investor confidence.

Future Outlook

The company plans to launch futures on the Bloomberg 500 Index and Bloomberg US 100 Price Return Index (B100Q Index) in the first half of 2026 on MIAX Futures, and cash-settled index options on the B500 Index on MIAX Options in 2026, subject to regulatory filings. They also intend to list other agricultural and financial futures products on the MIAX Futures Onyx platform starting in H1 2026. MIAXdx plans to expand access for participants by incorporating an intermediated FCM model and offering margin on cleared products, subject to CFTC approval. The company anticipates introducing innovative cryptocurrency and digital asset products on BSX, primarily for non-U.S. persons, leveraging Bermuda's regulatory environment. They will continue to expand market share in options, enhance technology, and monetize data and analytics capabilities.

Management Comments

• We are a technology-driven leader in building and operating regulated financial marketplaces across multiple asset classes and geographies.
• We believe the speed and performance of our proprietary technology coupled with our fully integrated, award-winning customer service, sets us apart from our competitors.
• We are regarded as a market leader relative to many of our peers with respect to our technology, based on feedback from our customers.
• We believe that this reliability provides our customers with an additional incentive to use our platforms to mitigate trade execution risk, especially in times of extreme market volatility.
• We believe we are well positioned to leverage our competitive strengths to enhance our market position, develop new products and services, and continue expanding into new asset classes and geographies.
• We believe that MIAX Futures is an attractive alternative to competitor DCOs given our partnership approach and track record of innovation and product development.
• We anticipate that these products (digital asset products on BSX) would not be made available to U.S. persons unless such persons are eligible under applicable law and we would, in consultation with counsel, implement appropriate procedures to ensure that the investors in any products meet the eligibility requirements of such products.
• We believe we are at an inflection point in our ability to further commercialize our market data.

Industry Context

The financial markets industry is characterized by heightened market volatility, growing retail investor participation, rapid technological advances, increased sophistication of trading strategies, and the proliferation of new asset classes like cryptocurrencies and event-based contracts. These trends drive increased trading volumes, especially in derivatives, and demand for shorter-duration contracts. The industry is intensely competitive, with numerous exchanges, OTC markets, and technology firms vying for market share based on cost, speed, functionality, and product offerings. Regulatory scrutiny, particularly in crypto-assets and market data fees, continues to shape the operational landscape. Consolidation and alliances among competitors are also prevalent.

Comparison to Industry Standards

• MIAX has grown to be the 13th largest global derivatives exchange operator as of September 30, 2025, as measured by total futures and options contracts traded, as reported by the Futures Industry Association (FIA).
• MIAX Options was ranked second in multi-listed options market share for electronic complex orders in 2024 and for the nine months ended September 30, 2025, according to Options Price Reporting Authority (OPRA) data.
• BSX is the global leader in the listing of Insurance Linked Securities (ILS) vehicles, providing catastrophic peril reinsurance coverage, representing approximately 92.7% of the global issuance as of September 30, 2025.
• TISE's Qualified Investor Bond Market (QIBM) is noted as a leading market in Europe for listing high yield bonds and private equity debt, with over 2,500 issuers and 4,500 securities listed.
• The company's MIAX Exchange trading platform is regarded as a market leader in technology relative to many peers, based on customer feedback, differentiating on throughput, latency, reliability, and wire-order determinism.
• MIAX Options, MIAX Emerald, MIAX Pearl, and MIAX Sapphire exchange markets demonstrated high operational uptime, with MIAX Sapphire at 100% for the remainder of 2024 after its August 2024 launch, and the combined exchanges at 99.99981641% for 9M 2025.
• The company's DCO license for MIAX Futures is unrestricted, allowing it to offer margin on cleared futures positions, which is highlighted as valuable compared to certain other DCOs that only offer fully collateralized clearing.

Management Changes

Corporate Governance

Legal Proceedings

• Ongoing patent infringement and trade secret misappropriation lawsuit filed by Nasdaq, Inc. in 2017. All six patent claims asserted by Nasdaq were invalidated by the PTAB in 2019, and Nasdaq waived its right to appeal in 2022. The court denied summary judgment motions from both parties on September 29, 2025, and will proceed with a two-phase trial: first trade secret claims, then the company's counterclaims (monopolization antitrust, patent misuse, sham litigation, fraud on USPTO).
• MIAXdx is responding to CFTC Division of Enforcement requests for information and documents related to activities prior to its acquisition by the company, during FTX's prior ownership. The outcome is unpredictable and could result in substantial costs, sanctions, and reputational harm.

Related Party Transactions

• Trading activity with exchange members (Citadel Securities, Strategic Investments I, Inc. (SII), Susquehanna Securities, Wolverine Holdings, LP) generated significant revenues and costs, all on terms no more favorable than to other customers.
• Equity Rights Program (ERP) transactions involved issuing warrants to certain stockholders (Citadel Securities, SII, Susquehanna Securities, Wolverine) in exchange for prepaid exchange fees and meeting trading volume targets. All ERPs expired by June 30, 2024.
• SII exercised put rights for ERP I and II shares, leading to deferred payments and subsequent sales of shares to other ERP participants, extinguishing the company's put obligation of $11.4 million in August 2025.
• In December 2023, the company issued 131,576 common shares to Citadel Securities and paid $2,388,088 to Wolverine for waiver and termination of their ERP put rights.
• Wolverine made a $1,518,559 loan to the company in December 2023, bearing 8% interest, and received a warrant to purchase 7,408 common shares.
• Citadel Securities acquired 92,611 common shares for $1,898,526 in December 2023 and received a warrant for 9,261 common shares.
• In June and August 2025, Citadel Securities exchanged 6,462,357 common shares (including non-voting) for pre-funded warrants to purchase 6,793,575 common shares, and an additional 575,071 common shares for a pre-funded warrant to purchase 575,071 common shares, both with a perpetual term and $0.002 exercise price.
• Affiliates of Warburg Pincus (Warburg Affiliates) provided a $100 million 2029 Senior Secured Term Loan in August 2024 and a $40 million Incremental Term Loan in June 2025, receiving warrants to purchase 3,795,564 common shares. All outstanding indebtedness was repaid in August 2025 using IPO proceeds.
• Murray Stahl, a director and >5% stockholder, is CEO of Horizon Kinetics Holding Corporation. Funds managed by Horizon Kinetics Asset Management LLC (HKAM) had convertible loans to the company, which were converted into common stock in 2024. HKAM-managed funds also purchased common stock and received warrants.
• Timur Tillyaev, a former >5% stockholder, provided convertible loans to the company, which were converted into common stock or had interest paid in common stock. Warrants held by Mr. Tillyaev and Securtrade were extended in November 2023.
• Paul Kotos, a former director, and his affiliated entity Capital Investing, LLC, received advisory fees totaling $2,025,000 from January 2022 to September 2025, and warrants were extended.
• John Beckelman, a director and Managing Director of Piper Sandler & Co. (PSC), was involved in financial advisory services agreements with PSC for the Dorman Trading acquisition ($500,000), MIAXdx acquisition ($650,000), and 2029 Senior Secured Term Loan ($6,125,000). PSC also received $7,637,438 for underwriting services in the IPO.
• Mark Massad, a director, is Senior Managing Director of KB Financial Companies, LLC, a OneDigital company. OneDigital received $300,000 for accounting-related advisory services for TISE in February 2025.
• Jack G. Mondel, a former director and current employee, had shares surrendered by Glenwood Advisors, LLC to cover tax obligations for a restricted stock award.
• Jassem Zainal (former director) and Talal Al-Bahar (director) are affiliated with Arzan Financial Group. Arzan provided a convertible loan to the company, which was converted into common stock in 2024, and received a warrant for 750,000 common shares for stockholder services.
• Lee Becker, a director, is a Managing Director of Warburg Pincus LLC, which had affiliates involved in the 2029 Senior Secured Term Loan.
• Dominique Prunetti-Miller (VP, Human Resources), child of former director Robert D. Prunetti, received cash compensation and equity awards. Tia Toms (VP, Administration), related party of former director Jack G. Mondel, received cash compensation and equity awards. Katherine Comly (former Associate VP), child of Executive VP Barbara J. Comly, received cash compensation and equity awards.

Stakeholder Impact

• **Shareholders:** Existing shareholders will experience dilution from the secondary offering as new shares are sold by existing holders, not the company. No dividends are currently intended to be paid, meaning returns depend on stock price appreciation. Exercise of outstanding options and warrants will further dilute ownership.
• **Employees:** IPO bonuses were paid to certain employees, and equity incentive plans are in place to align employee interests with stockholders. However, the company's fixed cost structure could impact profitability and, indirectly, employee compensation if revenues decline.
• **Customers:** New product offerings (e.g., Bloomberg Products, crypto-related products) and enhanced technology platforms aim to attract and retain customers. Competitive pricing models and liquidity payments are used to incentivize trading activity. However, regulatory changes (e.g., CAT funding, PFOF) could impact fees and services.
• **Suppliers/Vendors:** Dependence on third-party providers for key components and services means disruptions could impact operations. The company's growth strategy, including M&A, may lead to changes in vendor relationships.
• **Creditors:** The repayment of the 2029 Senior Secured Term Loan using IPO proceeds significantly reduced the company's debt burden. However, future debt may contain restrictive covenants. Clearing members face risks related to defaults by other members and liquidity risks within the clearing houses.

Next Steps

• Launch futures on the Bloomberg 500 Index and B100Q Index in the first half of 2026 on MIAX Futures, subject to regulatory filings.
• Launch cash-settled index options on the Bloomberg 500 Index on MIAX Options in 2026, subject to regulatory filings.
• Launch options on futures on the Bloomberg 500 Index on MIAX Futures, subject to regulatory filings.
• List other agricultural and financial futures products on the MIAX Futures Onyx trading platform beginning in the first half of 2026, subject to regulatory filings.
• Expand MIAXdx access for participants to incorporate an intermediated FCM model and offer margin on cleared products, requiring CFTC approval.
• Develop and launch additional cash-settled products on the MIAXdx DCM, subject to CFTC regulatory filings.
• Introduce additional functionality, expand data and analytics offerings, and implement pricing incentives for MIAX Pearl Equities.
• Continue defending interests vigorously in the Nasdaq patent infringement and trade secret misappropriation litigation, with discovery to re-initiate on counterclaims.
• Monitor and respond to evolving executive, legislative, and regulatory developments regarding crypto-assets and crypto-related products.
• Evaluate and design a new director compensation program for a publicly traded company.

Key Dates

Recommendation

The company demonstrates strong operational growth in its core Options segment, evidenced by significant increases in ADV and market share, and a substantial rise in adjusted EBITDA. Strategic acquisitions like TISEG expand its international footprint and product diversification, while new proprietary products like the Bloomberg Indexes show innovation potential. However, the recent net loss driven by a large debt extinguishment charge, coupled with declining market share in U.S. Equities and the dormancy of MIAXdx's SEF, presents headwinds. Ongoing legal proceedings and regulatory uncertainties, particularly regarding CAT funding and crypto-asset regulation, introduce additional risks. Given the mixed financial results, the secondary offering by selling stockholders (not raising capital for the company), and the balance of growth opportunities against operational and regulatory challenges, a 'hold' recommendation is appropriate. Investors should monitor the successful launch and adoption of new products, resolution of legal/regulatory matters, and sustained profitability in core segments.

Keywords

Secondary Offering, SEC Filing, Financial Markets, Exchange Operator, Options Trading, Futures Trading, Equities Trading, Clearing House, Derivatives, Market Data, Proprietary Technology, Regulatory Compliance, IPO, M&A, Bloomberg Products, Crypto Assets, Risk Management, Corporate Governance, Financial Performance, Market Share