# Philadelphia Semiconductor Index Falls for 8th Straight Session

> Philadelphia Semiconductor Index drops 11.5% weekly after 8 straight declines, matching longest streak since 2006 as AI trade unwinds.
- Title: Philadelphia Semiconductor Index Falls for 8th Straight…
- Summary: Philadelphia Semiconductor Index drops 11.5% weekly after 8 straight declines, matching longest streak since 2006 as AI trade unwinds. Philadelphia…
- Keywords: philadelphia semiconductor index, kosp, coreweave, credit default swaps, ai infrastructure, semiconductor supply chain, memory chips, leveraged etfs, circuit breaker, finance, markets, Philadelphia
- Source: BigGo Finance — https://finance.biggo.com/news/7cff82af-9e48-4149-9fcf-fa39c8946ae8
- Author: BigGo Finance
- Published: 2026-10-19T10:35:15+00:00
- Read time: 1 min
- Topics: philadelphia semiconductor index, kosp, coreweave, credit default swaps, ai infrastructure, semiconductor supply chain, memory chips, leveraged etfs, circuit breaker, finance, markets
## Philadelphia Semiconductor Index
Philadelphia Semiconductor Index falls for 8th straight session, matching longest losing streak since May 2006.
## Weekly Decline
Philadelphia Semiconductor Index drops 11.5% for the week and about 16% over eight sessions.
## KOSPI Decline
South Korea's KOSPI falls about 21% over seven sessions, triggering another circuit breaker.
## CoreWeave Impact
CoreWeave shares plunge 25% for the week as five-year CDS spread widens past 1,100 basis points.
## Credit Market Shift
CCC-rated bond spread widens to 12.78 percentage points while BAA-rated spread remains stable at 1.44 percentage points.
## Taiwan Market Activity
Taiwan's Weighted Index closes at 46,822.08 with foreign investors net sellers for ninth consecutive session.
## Nikkei 225 Movement
Nikkei 225 falls 3,318.34 points on Oct. 15, third-largest single-day point drop on record.
## Market Re-rating Focus
Market re-prices supply-side margin sustainability and sector concentration risk, not weakening demand.
## TSMC Results
TSMC reports third-quarter revenue up 50.9% year-on-year with net profit up 68.7% year-on-year.
## AI Infrastructure Financing
Nippon Life Insurance plans to double AI infrastructure financing from ¥1 trillion to ¥2 trillion by fiscal 2035.
## Semiconductor Concentration Risk
Semiconductors' share of KOSPI market capitalization rose from 25% in Q2 2025 to 60% range in June.
## Investor Strategy Shift
Investors should reduce concentration risk by diversifying into low-correlation assets like media and healthcare.
## Key takeaway

Philadelphia Semiconductor Index fell 11.5% for the week after 8 straight declines, matching its longest losing streak since May 2006 as crowded AI trades unwind.