Philadelphia Semiconductor Index (SOX) news that moved the stock

What happened

Taiwan's government moved over the weekend to arrest the rout in its stock market, and the measures took effect on Monday, November 9. The Financial Supervisory Commission cut the cap on intraday short-sale orders for borrowed shares to 3% of a stock's 30-day average daily volume, down from 30%, and raised the minimum margin for short sales to 130% from 90%, while encouraging buybacks. At an emergency meeting on Friday afternoon, the National Financial Stabilization Fund authorized its tenth-ever market-rescue operation, putting NT$500 billion (about $15 billion) on standby to buy stocks. The Taiex surged as much as 6.7% intraday and stood up 5.79% at 42,001.22 in midday trading, its biggest one-day gain since July 31, ending a seven-session losing streak; TSMC gained about 4.7%, MediaTek more than 4% and Foxconn about 6.5%. South Korea acted in parallel, suspending the margin-loan collateral rule that forces brokers to liquidate leveraged retail accounts; SK Hynix gained about 4.6% and Samsung about 2.4%. Nasdaq 100 futures, down about 0.8% at Sunday's open on the Nvidia probe news, recovered to roughly flat by Monday morning.

What happened

JPMorgan upgraded Intel (INTC) to Neutral from Underweight on Monday morning, October 19, 2026. Intel shares rose about 3.8% in premarket trading on the upgrade, and the Wall Street Journal also flagged Intel up more than 3% premarket after slumping 5.8% on Friday. The upgrade comes as AI-linked and semiconductor stocks attempt to rebound from last week's sharp selloff.

What happened

Per IDC data seen by Reuters, Nvidia's share of China's data-centre AI chip market fell to 34% in the first half of 2026 as U.S. export controls limited the range of products it can sell. Nvidia shipped 678,000 AI accelerators in China from January through June, down 44% from a year earlier. Huawei closed the gap substantially, shipping 572,000 AI accelerators — up from more than 300,000 a year earlier — for a 28% share. Beijing has additionally required Chinese companies to seek approval to import compliant Nvidia chips. Nvidia did not respond to a request for comment.

What happened

The chip sector sold off broadly on Monday in what MarketWatch described as a fourth straight decline and its lowest close since Sept 18, with all 30 PHLX Semiconductor Index components losing ground and the SOX shedding 2.3%. Nvidia fell 1.7% to about $226, extending a pullback to roughly 5.8% since its $239.24 record close on Oct 6. The damage was heaviest in memory and photonics: Micron and Marvell were down more than 4%, Sandisk fell 6%, and Lumentum and Coherent were among the biggest S&P 500 decliners. The S&P 500 Information Technology sector was the index's worst performer, down about 1%, even as the broader market held mixed.

What happened

Bloomberg reported on Oct 9 that OpenAI has told prospective investors it expects annualized revenue to reach or exceed $70 billion by the end of 2026, driven largely by growth in its enterprise business. The ChatGPT-maker's annualized revenue was roughly $50 billion at the end of September, the report said — but the company shared the $70B year-end figure with investors as part of discussions for its latest fundraising round, in which it is in talks to raise $30B or more at a $1.4 trillion pre-money valuation. The report directly countered Thursday's Financial Times account that had triggered a broad AI-stock sell-off (Nasdaq 100 -1.4%), and software stocks rebounded sharply on Friday: Zscaler +7.8%, Snowflake +7.4%, Datadog +7.1%, Palantir +5.2% to a new all-time high, Microsoft +2.4%.