Private Debt

Private debt is a form of direct lending where non-bank lenders — including private credit funds, business development companies (BDCs), and CLOs — provide loans to middle-market and large corporate borrowers outside the public bond and syndicated loan markets. Borrowers access private debt for speed, certainty of close, and flexibility on terms that public markets cannot match.

Allocator Relevance: Private debt has become a core fixed-income replacement for LPs seeking yield above investment-grade bonds without full equity volatility. Floating-rate structures provide natural inflation protection; senior secured positions offer downside mitigation.

Market Growth

The SEC's Form PF data records 7,744 other private funds (the category encompassing most private credit strategies) with $1.86 trillion in aggregate NAV as of Q3 2025. Private debt AUM has grown from roughly $300 billion in 2010 to over $1.7 trillion today, driven by bank regulatory pullback following the GFC and institutional demand for yield. Source: SEC Form PF Q3 2025, aggregated by Altss.

Origins

The private debt industry expanded dramatically after the 2008 financial crisis. Basel III capital requirements forced banks to reduce leveraged lending, creating a structural gap that private credit funds filled. Managers like Ares, Apollo, and Blackstone scaled rapidly, and what had been a niche CLO and mezzanine market became a mainstream institutional asset class.

How Private Debt Works

A private debt fund raises capital from LPs and deploys it as loans — typically senior secured, first-lien positions — to operating companies. The fund earns interest income (usually SOFR + 400–700 bps) plus origination fees. Unlike public bonds, loans include negotiated covenants, PIK provisions, and equity co-investments. Capital is returned through loan repayments and refinancings over a 5–7 year fund life.

Sub-Strategies

• Direct lending — first-lien senior secured loans to middle-market companies; lowest risk in the capital stack
• Mezzanine — subordinated debt with equity kickers; higher yield, more risk than senior
• Distressed debt — loans to companies in financial difficulty; return via restructuring and recovery
• Asset-based lending — loans secured against specific assets (receivables, inventory, IP)
• Unitranche — single blended facility combining senior and subordinated debt for simplicity

Risk and Return

Target net IRRs range from 8–12% for senior secured direct lending to 15–18% for mezzanine and distressed. The primary risks are credit loss (borrower default), covenant erosion (covenant-lite structures reduce lender protection), and liquidity — private loans cannot be sold easily in stress scenarios. Floating-rate structures benefit from rate rises but increase borrower default risk simultaneously.

Common Misconceptions

• Private debt is not equivalent to high-yield bonds — covenants, seniority, and direct negotiation with borrowers create fundamentally different risk/return
• Floating rate is not purely positive — higher rates increase default probability for leveraged borrowers, creating credit risk alongside yield benefit
• Private debt funds are not liquid — despite shorter durations than PE, capital is locked; redemptions are not available on demand

Key Takeaways

• 7,744 other private funds held $1.86T in NAV as of Q3 2025; private credit AUM has grown 5x since 2010 (SEC Form PF, aggregated by Altss)
• Senior secured direct lending targets 8–12% net IRR; subordinated and distressed strategies target 15–18%
• LP due diligence must examine covenant quality, leverage multiples, and borrower industry concentration