MIAMI INTERNATIONAL HOLDINGS, INC. (MIAX) stock intrinsic value fair value estimate & owner earnings analysis

MIAX operates U.S. options, equities and futures exchanges (MIAX Options, Pearl, Emerald, Sapphire; MIAX Futures and clearing; Dorman Trading) plus an international arm that includes the Bermuda Stock Exchange. It earns transaction and clearing fees, market data and connectivity (access) fees. Reported revenue (about $1.36 billion in 2025) is inflated by pass-through items such as liquidity rebates and SEC fees; the number that matters is revenue less cost of revenues, which rose from $276 million in 2024 to $431 million in 2025 and was running about 37% higher in the first half of 2026 than a year earlier. How we measured earnings: we started from operating cash flow and removed working-capital swings (large and noisy here because clearing-house margin and performance-bond balances move through operating cash flow), then subtracted stock compensation and maintenance capital spending (about 2.8% of reported revenue is spent on equipment and software; only a small slice was treated as growth spending). We also removed a one-time $16 million of intangible-sale proceeds that were booked in operating cash flow. Large non-cash items that swung the reported net loss of $70 million in 2025 (a $108 million charge for retiring debt at the August 2025 IPO and a $55 million mark-down of Pyth tokens) are not cash and do not enter the result. Owner earnings were roughly -$9 million in 2023, $40 million in 2024 and $96 million in 2025. Only three years of filings are available because the company only recently began filing as a public company, so there is little history to lean on. Anchor and growth: the business changed materially in 2025 (IPO, debt essentially eliminated, new options platform and a step-change in profitability), so 2023 and 2024 describe a different, less profitable company. We began from 2025 owner earnings of about $96 million and lifted the level modestly, to about $105 million, because the last four quarters of operating income (about $116 million versus $92 million in fiscal 2025) corroborate a higher level. That is about $0.95 per share on the roughly 110.7 million diluted shares now outstanding (the 2025 per-share figure of $1.37 used a share count that averaged only 69.8 million because the IPO came in August). Owner earnings grew about 139% in 2025; our first-year growth assumption is 0%, below that, because nothing contracted or repeatable carries that pace forward. Growth from market share gains, new products (Sapphire, futures) and rising volumes is left out, since it is not yet secured or proven through a downturn. Cases: Base assumes about $105 million a year for three years, then about $75 million a year as the company's $258 million of federal tax loss carryforwards run out (they can offset only 80% of taxable income, and 2025 cash taxes were under $1 million), and then about three quarters of that level persisting because exchange licenses, connectivity and data revenue are sticky structural features. That is about $10.4 per share. Bear assumes the level falls back to roughly the 2024 result (about $45 million, then $38 million after tax shields end) because roughly 61% of revenue less cost of revenues comes from volume-dependent net transaction fees and the company itself states that a shift to lower-revenue products or lower volumes would reduce them; half of that persists after year 10; about $4.3 per share. Bull assumes the first half of 2026 run-rate holds (about $150 million, $115 million after taxes begin) with 85% persisting afterward; about $16.7 per share. What could make this wrong: Pyth tokens (some unlock in 2026 to 2028) and any sale proceeds are excluded because their cash value is not established. Stock compensation fell sharply in 2026 after IPO-related awards in 2025; if it returns to prior levels, owner earnings would be lower. Capital spending stepped up in the first half of 2026 (about $33 million). Second-half 2026 results and quarterly working-capital detail could not be reconciled from the filings provided. Because the operating history is short, volume-driven and the tax position is about to change, the margin-of-safety price sits well below the base case.