Price and volume data below is from Alpha Vantage’s market data feed, last updated 2026-09-21 16:15 US/Eastern. News context is drawn from same-day reporting by Reuters, CNBC, and Investopedia. This is a factual recap of trading activity, not investment advice. See our disclaimer.
The backdrop: a record close for the Nasdaq
Monday, September 21 was a strong session for technology stocks. The Nasdaq Composite closed at a record high, chip stocks led, and the PHLX Semiconductor Index gained more than 4%. Two things helped: US crude oil fell sharply, and Treasury yields pulled back from recent highs, which eased pressure on growth-stock valuations. Advanced Micro Devices rose about 10% to an all-time high and topped $1 trillion in market value for the first time, and Meta Platforms gained roughly 11%.
That context matters when reading the movers list below: several of the day’s big moves were part of a sector-wide rally, not isolated company news.
Most actively traded
Trading volume today was concentrated in a handful of names:
- WBD (Warner Bros. Discovery) closed at $30.80, up 10.79%, with over 233 million shares traded.
- INTC (Intel) closed at $121.78, up 12.14%, with roughly 188 million shares changing hands, well above its typical daily volume.
- BTTC was the most active ticker by share count (over 418 million shares), up 117.75%. High share counts in low-priced stocks can look impressive while representing far less money than the large-cap names above.
Why Intel jumped
Intel’s gain came alongside the broader AI and chip rally. Same-day coverage pointed to several factors: renewed confidence that AI infrastructure spending is still growing, attention on Meta’s new AI agent and what it could mean for demand for server CPUs, and reports that SK Hynix is exploring a manufacturing arrangement with Intel. Arm Holdings, another CPU designer, rose even more on the day. Analysts quoted in coverage also flagged the risks: valuation after a long rebound, foundry execution, and competition in AI processors.
Why Warner Bros. Discovery jumped
WBD’s move was deal news. Reports over the weekend and on Monday said Paramount Skydance had reached a settlement with the state attorneys general whose lawsuit was blocking its planned acquisition of Warner Bros. Discovery. When a pending takeover looks more likely to close, the target’s shares typically move toward the offer value, which is what WBD did. Paramount shares rallied early but reportedly closed lower, a common pattern for acquirers.
Top gainers: read the fine print
The day’s biggest percentage gainers were dominated by small and micro-cap names, led by GRML (+230.5%), GLNDW (+186.2%), and GLND (+141.3%). Stocks tied to Greenland were in the news after a US security announcement about the island, and several of them spiked. Note the W at the end of GLNDW: on Nasdaq, a fifth-letter W usually marks a warrant, a separate security that gives the right to buy shares at a set price, not the common stock itself. Warrants often swing far more than the underlying shares.
Top losers
On the downside, the largest percentage declines included RIV^ (-69.6%) and ASGI^# (-61.1%). Symbols with suffixes such as ^ and # typically denote rights or when-issued securities rather than ordinary common stock. Big percentage drops in these instruments often reflect how they work, for example a rights offering approaching expiration, rather than a collapse in the underlying company.
Takeaway
The meaningful moves today were Intel and Warner Bros. Discovery: large, widely held companies posting double-digit gains on heavy volume, each with an identifiable catalyst. The triple-digit percentage moves at the top of the gainers list mostly came from low-priced stocks, warrants, and other special securities, where small amounts of money can move prices a long way. Before reacting to any headline percentage, check the dollar volume and what kind of security you are looking at. Our explainer on most active vs. biggest movers walks through how.
