A CLO that holds directly originated middle-market loans (typically 50–80 loans, $300–$500M pool size) rather than broadly syndicated loans. Versus BSL CLOs, MM CLOs have lower leverage (4–5× debt-to-equity vs. 9–10×), wider AAA spreads (SOFR + 175–225 bps vs. 130–150 bps), and lower equity yields (10%–15% vs. 12%–18%) — the price of holding illiquid, less-correlated collateral. Manager flexibility is also lower: MM CLOs are primarily hold-to-maturity vehicles reinvesting only prepayments.