AI Market Watch · Archive report

29 September 2026

Broader high-yield credit has started to weaken.

Published Compared with the 25 September 2026 report

Transmission chain

Stage 3

Forced deleveraging. Entry evidence confirmed 11 Sept; earliest downgrade 11 Oct.

AI economics

Watch

Level 2 of 5, from Calm to Critical.

1HeadlinesWhat does this mean?

Stage 3 (forced deleveraging), unchanged from the last report; earliest downgrade 11 October. AI economics: Watch, unchanged.

The bad

  • Broader high-yield credit has started to weaken: US high-yield risk premiums reached their widest level in five months, with the spread closing at 302bp.23
  • September junk-bond issuance was already about $38.5bn, the busiest month of 2026, and the volume of supply was beginning to overwhelm investors.4
  • The rates shock worsened again, with the US 10-year Treasury around 5.23% and the dollar near a two-month high.1

The good

  • No fresh evidence of another major margin call, forced fund liquidation, data-centre financing failure or acceleration in private-credit markdowns.
  • Broad credit is still inside Calm: high-yield 302bp against a 350bp Watch line and investment-grade 83bp.313

Not what it looks like

  • The high-yield widening is not yet credit contagion. It appeared substantially driven by supply indigestion rather than investors suddenly expecting a wave of defaults.

2ScorecardWhat does this mean?

Pillar Status Trend Why
AI equities Watch Unchanged The semiconductor index closed 14.8% below its 52-week high, inside the Watch band.5 No new equity evidence in this report.
Rates and macro Elevated Unchanged The 10-year closed at 5.24%, a basis point short of the Stressed threshold, and the 30-year at 5.56%.89 The report puts the 10-year around 5.23% with the dollar near a two-month high.1
Broad credit (the firewall) Calm Unchanged High-yield 302bp and investment-grade 83bp, both still inside Calm.313 But high-yield risk premiums are at their widest in five months, so the firewall has weakened: until now, AI-related credit could deteriorate while mainstream corporate credit remained conspicuously calm.2
AI-specific credit Elevated Unchanged No new AI credit pricing in this report; status held from the 25 September report. The report treats AI-specific credit as already repriced.
AI financing flow Elevated Unchanged September junk-bond issuance of about $38.5bn made it the busiest month of 2026, and the report counts enormous AI and high-yield debt supply as the source of the indigestion now hitting broader spreads.4 No data-centre financing failure in this report.
Leverage and liquidity Elevated Unchanged No fresh evidence of another major margin call or forced fund liquidation. Status held from the 25 September report.
Private credit Elevated Unchanged No acceleration in private-credit markdowns. Status held from the 25 September report.
AI economics Watch Unchanged No new evidence in this report; status held from the 25 September report.

3Change since last reportWhat does this mean?

Compared against the 25 September 2026 report, back-scored the same way. Scores for this report were back-scored on 4 November 2026 from its own text and from FRED and Yahoo Finance closing data, because it predates the scorecard format.

Last report (25 Sep) This report Change
Stage 3 (evidence 11 Sep) 3 (evidence 11 Sep) Unchanged. No fresh margin call or forced liquidation; Stage 3 still rests on the 11 September Situational Awareness evidence, with the earliest downgrade on 11 October.
AI economics Watch Watch Unchanged. No new evidence on capex or cash flow in either report.
AI equities Watch Watch Unchanged. The drawdown was little changed at 14.8%.5
Rates and macro Elevated Elevated Unchanged. Worse inside it: the 10-year closed at 5.24%, up from 5.18% and a basis point short of Stressed, with the dollar near a two-month high.81
Broad credit Calm Calm Unchanged. Worse inside it: high-yield widened from 280bp to 302bp, its widest in five months, and investment-grade from 79bp to 83bp. Still inside Calm, but the firewall is no longer conspicuously calm.313
AI-specific credit Elevated Elevated Unchanged. No new AI credit pricing in this report.
AI financing flow Elevated Elevated Unchanged. Worse inside it: September junk-bond issuance reached about $38.5bn and supply was beginning to overwhelm investors.4
Leverage and liquidity Elevated Elevated Unchanged. No fresh margin calls or forced liquidations in either report.
Private credit Elevated Elevated Unchanged. No acceleration in private-credit markdowns.

Net: no pillar status moved and the stage held at 3. The new development is that broad high-yield credit, which had stayed calm while AI credit repriced, has started to widen, which puts Stage 4 on the chain as partial for the first time. Rates also edged to within a basis point of Stressed. Both moves built inside unchanged statuses.

History across the last 13 reportsCalm at the top, Critical at the bottom: a red step down is worse, a green step up is better.
Transmission stageStage 3
AI equitiesWatch
Rates and macroElevated
Broad creditCalm
AI-specific creditElevated
AI financing flowElevated
Leverage and liquidityElevated
Private creditElevated
AI economicsWatch
3 Sep28 Sep

4Transmission chainWhat does this mean?

  1. 1 AI equity correction Partial evidence
  2. 2 AI-specific credit stress Confirmed
  3. 3 Forced deleveraging Confirmed 11 Sept Earliest downgrade 11 Oct
  4. 4 Firewall breached Partial evidence
  5. 5 Systemic liquidity event Not present
Stage Status
1 — AI equity correction Partial. The Stage 1 tripwire cleared on 24 September; the semiconductor index is 14.8% below its 52-week high, a Watch-level drawdown.5
2 — AI-specific credit stress Confirmed. Confirmed from 22 September on Project Jupiter failing to syndicate and the AI investment-grade premium. This report treats AI-specific credit as already repriced, with enormous AI and high-yield debt supply still to come.
3 — Forced deleveraging Confirmed. Entry evidence 11 September: JPMorgan curbing lending to Situational Awareness after its margin call and forced liquidation. No fresh margin call or forced fund liquidation in this report. Earliest downgrade 11 October.
4 — Firewall breached Partial. High-yield risk premiums at their widest in five months, at 302bp, so the firewall has started to weaken.23 The tripwires are far off (450bp high-yield, 130bp investment-grade), and the widening appears substantially driven by supply indigestion rather than default expectations.
5 — Systemic liquidity event Not present. No funding-market malfunction reported.

5JudgementWhat does this mean?

This report’s meaningful deterioration comes from broader high-yield credit starting to weaken.23 US high-yield risk premiums reached their widest level in five months. September junk-bond issuance was already about $38.5bn, the busiest month of 2026, and the volume of supply was beginning to overwhelm investors.4 That does not yet constitute credit contagion: the widening appeared substantially driven by supply indigestion rather than by investors suddenly expecting a wave of defaults. But it weakens the firewall. Until now, AI-related credit could deteriorate while mainstream corporate credit remained conspicuously calm.

At the same time the rates shock worsened again, with the US 10-year around 5.23% and the dollar near a two-month high.1 The combination became:

Treasury yields >5.2% → AI-specific credit already repriced → enormous AI/high-yield debt supply → broader HY spreads now widening → dollar strengthening.

There was no fresh evidence of another major margin call, forced fund liquidation, data-centre financing failure or acceleration in private-credit markdowns. This was therefore a moderate but meaningful escalation, not a regime change.

6Key indicatorsWhat does this mean?

Market data as at the close on 28 September 2026, compared with the close used by the 25 September 2026 report (24 September 2026). Reported figures are carried forward from the report that last cited them until a newer one appears.

Indicator Latest Previous Change Tripwire Source
AI equities
PHLX Semiconductor Index (SOX) 12,465; 14.8% below its 52-week high (22 Jun) 12,493 −0.2% Stage 1 when more than 20% below its 52-week high for five closes Confirmed, Yahoo Finance ^SOX5
Nasdaq 100 30,277 30,479 −0.7% Context Confirmed, Yahoo Finance ^NDX6
KOSPI 6,890 7,081 −2.7% Context Confirmed, Yahoo Finance ^KS117
Rates and macro
US 10-year Treasury 5.24% 5.18% +0.06pp Elevated 4.75–5.25%; Stressed above 5.25%, each for five closes Confirmed, FRED DGS108
US 30-year Treasury 5.56% 5.47% +0.09pp Context Confirmed, FRED DGS309
Brent crude $119.97 $120.92 −0.95 Context Confirmed, FRED DCOILBRENTEU10
US dollar index (broad) 120.70 120.55 +0.1% Context Confirmed, FRED DTWEXBGS11
Yen per US dollar ¥157.44 ¥158.92 −1.48 Context Confirmed, FRED DEXJPUS12
Broad credit
ICE BofA US investment-grade spread 83bp 79bp +4bp Watch at 100bp; Stage 4 above 130bp for five days Confirmed, FRED BAMLC0A0CM13
ICE BofA US high-yield spread 302bp 280bp +22bp Watch at 350bp; Stage 4 above 450bp for five days Confirmed, FRED BAMLH0A0HYM23
ICE BofA CCC & lower spread 1,146bp 1,112bp +34bp Early warning only Confirmed, FRED BAMLH0A3HYC14
ICE BofA CCC & lower effective yield 16.40% 16.04% +0.36pp Early warning only Confirmed, FRED BAMLH0A3HYCEY15
AI-specific credit
AI investment-grade premium over the broad index ~115bp vs 78bp broad IG (22 Sep report) ~115bp vs 78bp broad IG no new reading n/a Carried from the 22 September report
Oracle 5-year CDS Not yet reported in the series — — n/a —
Meta 5-year CDS Not yet reported in the series — — n/a —
CoreWeave 5-year CDS Not yet reported in the series — — n/a —
SoftBank 5-year CDS ~385bp (from ~280bp in June) (23 Sep report) ~385bp (from ~280bp in June) no new reading n/a Carried from the 23 September report
Named data-centre project debt Project Jupiter (~$18bn) quoted 89–91c (19 Sep report) Project Jupiter (~$18bn) quoted 89–91c no new reading n/a Carried from the 19 September report
Semiconductor index, % below its 52-week high14.8%
10%15%20%25%Stage 1 tripwire 20%31 Aug28 Sep

Yahoo Finance ^SOX, daily closes to 28 Sep.

US 10-year Treasury yield5.24%
4.6%4.8%5%5.2%5.4%Elevated 4.75%Stressed 5.25%31 Aug28 Sep

FRED DGS10, daily closes to 28 Sep.

ICE BofA US investment-grade spread83bp
60bp80bp100bp120bp140bpWatch 100bpStage 4 tripwire 130bp31 Aug28 Sep

FRED BAMLC0A0CM, daily closes to 28 Sep.

ICE BofA US high-yield spread302bp
250bp300bp350bp400bp450bpWatch 350bpStage 4 tripwire 450bp31 Aug28 Sep

FRED BAMLH0A0HYM2, daily closes to 28 Sep.

Faint vertical lines mark each of the last 13 reports. Dashed red lines are the published thresholds.

What would change our view

Would make it worse (up toward Stage 4): High-yield above 450bp or investment-grade above 130bp for five consecutive trading days, or widening that persists after the September supply clears; five consecutive 10-year closes above 5.25%, which would make rates Stressed; another major margin call, forced fund liquidation or data-centre financing failure.

Would make it better (down to Stage 2): A month with no new forced-selling evidence after the Situational Awareness margin call and liquidation reported on 11 September, so not before 11 October, provided Stage 2’s own evidence is still confirmed.

Would move the AI-economics axis: Hyperscalers cancelling or sharply cutting AI capex, or evidence that the higher cost of debt is delaying AI infrastructure projects.

7SourcesWhat does this mean?

  1. Reuters — The 5% threshold (2026-09-24) — reconstructed-match
  2. Reuters — Corporate bond buyers get picky with flood of AI debt (2026-09-22) — reconstructed-match
  3. Federal Reserve Bank of St. Louis (FRED) — ICE BofA US High Yield Index Option-Adjusted Spread (continuous) — official-data-series
  4. Investing.com (reporting Goldman Sachs) — Goldman warns high-yield bond supply surge pressuring markets (2026-09-28) — reconstructed-match
  5. Yahoo Finance — PHLX Semiconductor Index (^SOX) price history (continuous) — market-data-series
  6. Yahoo Finance — Nasdaq 100 (^NDX) price history (continuous) — market-data-series
  7. Yahoo Finance — KOSPI (^KS11) price history (continuous) — market-data-series
  8. Federal Reserve Bank of St. Louis (FRED) — 10-Year Treasury Constant Maturity Rate (continuous) — official-data-series
  9. Federal Reserve Bank of St. Louis (FRED) — 30-Year Treasury Constant Maturity Rate (continuous) — official-data-series
  10. Federal Reserve Bank of St. Louis (FRED) — Crude Oil Prices: Brent - Europe (continuous) — official-data-series
  11. Federal Reserve Bank of St. Louis (FRED) — Nominal Broad U.S. Dollar Index (continuous) — official-data-series
  12. Federal Reserve Bank of St. Louis (FRED) — Japanese Yen to U.S. Dollar Spot Exchange Rate (continuous) — official-data-series
  13. Federal Reserve Bank of St. Louis (FRED) — ICE BofA US Corporate Index Option-Adjusted Spread (continuous) — official-data-series
  14. Federal Reserve Bank of St. Louis (FRED) — ICE BofA CCC & Lower US High Yield Index Option-Adjusted Spread (continuous) — official-data-series
  15. Federal Reserve Bank of St. Louis (FRED) — ICE BofA CCC & Lower US High Yield Index Effective Yield (continuous) — official-data-series

Not investment advice. Scoring, tripwires and the persistence rule are set out in How to read the AI Market Watch; terms are explained in the explainers.

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