The Securities and Exchange Commission (SEC) 13F + 13G filings for the period ending March/April 2026 confirm: BlackRock holds 15.81% of Maximus (8,625,703 shares, $562.6 million valuation — single largest institutional holder), Vanguard 11.42% (6,227,259 shares aggregated across portfolio management divisions), State Street Global Advisors 4.56% (2,488,491 shares). Combined Big Three = 31.79%.
This Figure aligns with the engine's canonical 15-30% pattern observed across major US-listed federal-contracting entities. Engine framing: the federal-services-throughput layer is owned and directed by the EXACT SAME centralized financial architecture (the Layer-2 autonomous mechanic per the blackrock node) that controls the bio-industrial and defense-technology bases.
BlackRock's Aladdin risk-modeling platform actively incorporates Maximus debt issuances into its Fixed Income Universe ETFs (e.g., iShares Core Universal USD Bond ETF / IUSB / BTOT), tying Maximus's corporate paper directly to the engine's documented foundational liquidity layer. Maximus also conducted significant stock repurchases in FY2025 — retiring 5.8M shares for $457 million — actively consolidating equity value and dividend yields for its Big Three institutional holders.