NEW YORK, NY – September 5, 2026 (STL.News) Most Shorted – Short sellers are making some sizable bets against several prominent S&P 500 companies, creating a group of stocks that investors may want to keep on their radar as Wall Street moves into the final months of 2026.
Among the heavily shorted S&P 500 names attracting attention are Charter Communications Inc. (NASDAQ: CHTR), Super Micro Computer Inc. (NASDAQ: SMCI), Moderna Inc. (NASDAQ: MRNA), Lululemon Athletica Inc. (NASDAQ: LULU) and APA Corp. (NASDAQ: APA).
The latest reported short-interest figures generally reflect positions as of August 14, 2026, with the data subsequently released in late August. Because exchange short-interest figures are reported periodically rather than continuously, view them as a snapshot rather than a real-time measurement.
Even so, the numbers reveal some significant bearish positioning.
Short-interest percentages can vary among financial-data services because providers sometimes calculate the public Float differently. The raw number of shares sold short is therefore another important number to watch.
Most Shorted – Charter Communications Has a Major Short Position
Charter Communications stands out immediately.
As of August 14, approximately 22.98 million Charter shares were sold short, representing about 19.48% of its public Float under MarketBeat’s calculation. Short interest increased 2.3% from the previous reporting period.
Perhaps even more significant is Charter’s 12.3 days-to-cover ratio.
Days to cover estimates how many average trading days would theoretically be required for short sellers to purchase enough shares to close all outstanding short positions.
A high figure doesn’t guarantee a squeeze. However, when a heavily shorted company suddenly produces unexpectedly good news, short sellers trying to exit can add substantial buying pressure.
Charter’s short position has also grown substantially during 2026.
On March 31, approximately 17.78 million shares were sold short. By August 14, that figure had increased to nearly 23 million. Short interest as a percentage of Float increased from roughly 14.6% to 19.5% over the same period.
The bearish positioning comes against a difficult stock-price backdrop. Charter closed September 1 at $146.19, nearly 49% below its 52-week high of $285.82, according to MarketWatch.
That decline helps explain why bears have remained interested.
But it also makes Charter one of the more intriguing stocks on this list because of its large short Float and unusually high days-to-cover.
Most Shorted – Super Micro Computer Has 91 Million Shares Short
If Charter is notable for its days-to-cover ratio, Super Micro Computer stands out for the sheer number of shares being bet against.
As of August 14, approximately 91.22 million SMCI shares were sold short.
That represented about 18.08% of the company’s public Float, with the short position valued at about $3.63 billion based on the price on the reporting date.
Super Micro has become one of Wall Street’s more volatile artificial-intelligence infrastructure stocks.
The company’s servers and computing platforms are connected directly to the enormous investment in AI data centers. That creates considerable upside expectations, but also leaves the stock vulnerable whenever investors question growth rates, margins, spending trends, or valuation.
Interestingly, short sellers have recently reduced their positions somewhat.
SMCI’s short interest peaked at more than 103 million on June 30, representing about 20.5% of Float. By August 14, that had fallen to 91.22 million.
That decline suggests at least some bears have already reduced exposure.
SMCI’s squeeze dynamics also differ considerably from Charter’s.
Super Micro has enormous daily trading volume, producing a days-to-cover ratio of only about 1.37 days. That means shorts can theoretically exit much faster than they could in Charter.
Still, 91 million shares sold short is a substantial position.
The stock has demonstrated how quickly it can move. SMCI jumped about 19% on August 12, after several volatile trading sessions in August.
A strong earnings report, major AI contract, or unexpectedly bullish guidance could therefore create significant pressure on bearish positions.
Most Shorted – Moderna Shows What a Short Squeeze Can Look Like
Moderna may be the most fascinating stock in this group because investors have already seen what happens when heavy short interest collides with major positive news.
As of August 14, short sellers controlled approximately 52.81 million Moderna shares, or 14.83% of the company’s public Float.
Short interest had actually increased 6.1% from 49.77 million shares during the previous reporting period.
The days-to-cover ratio stood at approximately 9.15 days, another elevated figure.
Then came the catalyst.
On August 19, Moderna released positive late-stage results involving its personalized mRNA cancer treatment developed with Merck. Moderna shares exploded higher, rising roughly 177% during one session as investors reassessed the potential value of the company’s oncology pipeline. Heavy short positioning amplified the move as some bearish traders were forced to buy shares to close positions.
The event provides a near-textbook illustration of short-squeeze mechanics.
A trader who sells a stock short first borrows shares and sells them, expecting to purchase them back later at a lower price.
If the stock instead rises sharply, losses can grow rapidly.
Unlike buying a stock, where the theoretical maximum loss is the amount invested, short selling can create theoretically unlimited losses because there is no mathematical ceiling on how high a stock can rise.
When enough short sellers rush to buy shares at the same time, those purchases can push the stock even higher.
Moderna’s rally demonstrated that process dramatically.
The company’s stock has subsequently become one of the S&P 500’s strongest performers of 2026, making it an unusual combination: one of the year’s biggest winners while still carrying substantial reported short interest.
That makes the next short-interest report particularly important. It will show how many bearish investors remained after Moderna’s explosive August move.
Most Shorted – Lululemon Short Interest Is Rising Fast
Lululemon presents a different situation.
Short sellers held about 10.80 million LULU shares as of August 14, roughly 9.15% of the public Float.
What makes Lululemon especially noteworthy isn’t just the percentage.
It’s the trend.
Short interest increased 9.7% from the previous reporting period.
Bearish positions have been growing for months.
At the end of March, approximately 4.53 million Lululemon shares were sold short, representing around 3.8% of Float. By August 14, the short position had grown to 10.80 million shares and more than doubled as a percentage of Float.
That shift in investor positioning is significant.
And the bears received additional support Friday.
Lululemon shares plunged approximately 17.4% on September 4 after the company lowered its forecast, making the stock one of Friday’s major S&P 500 decliners.
That decline highlights an important distinction between Lululemon and Moderna.
For Moderna, the catalyst went violently against short sellers.
In Lululemon, recent corporate developments have moved in the direction short sellers were anticipating.
What happens next will depend on whether operating performance deteriorates further or whether the reduced share price begins attracting investors betting on a recovery.
Most Shorted – APA Corp. Bears Have Been Covering
APA Corp., the oil and gas exploration company, presents another interesting case.
Approximately 26.11 million APA shares were sold short as of August 14, representing about 7.51% of public Float.
That is still elevated relative to many large S&P 500 companies.
However, unlike Charter, Moderna, and Lululemon, the direction is moving sharply lower.
APA short interest fell approximately 13.2% from the previous reporting period, when more than 30 million shares were sold short.
That indicates bears have been actively closing positions.
Energy stocks have also faced an unusual macroeconomic environment in recent weeks as oil prices have reacted to geopolitical developments in the Middle East.
Crude prices jumped sharply at the end of August as conflict-related concerns intensified, helping support energy stocks even while broader equity markets declined.
For an oil producer such as APA, rising crude prices can rapidly change earnings expectations.
That means short sellers aren’t merely betting on company-specific factors. They’re also exposed to commodity prices that can move dramatically because of geopolitical developments completely outside the company’s control.
Most Shorted – What Short Interest Actually Tells Investors
High short interest shouldn’t automatically signal bullishness or bearishness.
Short sellers can be right.
Companies facing weakening earnings, deteriorating fundamentals, or excessive valuations sometimes attract high short interest precisely because sophisticated investors believe the stock price doesn’t reflect those problems.
But short sellers can also be spectacularly wrong.
The Moderna rally demonstrated the danger.
That’s why investors frequently watch three measurements together:
Short percentage of Float shows how much of the freely tradable stock has been sold short.
Shares sold short reveals the absolute size of the bearish position.
Days to cover estimates how difficult it could be for short sellers collectively to exit those positions.
A stock with 20% short interest but enormous trading volume may be easier for bears to exit than a stock with somewhat lower short interest but limited liquidity.
Charter illustrates that distinction particularly well.
Its roughly 19.5% short float is high, but the 12.3 days-to-cover figure potentially makes the position more consequential.
Most Shorted – Five S&P 500 Stocks Worth Watching
Among these five companies, the risk facing short sellers isn’t identical.
Charter Communications combines high short interest with the highest days-to-cover ratio in this group.
Super Micro Computer carries an enormous absolute short position of more than 91 million shares but very high trading liquidity.
Moderna has already demonstrated how violently a major catalyst can punish shorts.
Lululemon has seen bearish positioning increase dramatically while its shares face renewed pressure.
APA remains heavily shorted compared with many S&P 500 stocks, although bearish traders have recently been covering positions.
Together, these stocks provide a window into one of Wall Street’s most aggressive strategies.
Short sellers aren’t simply predicting that a stock will underperform the market.
They are putting capital behind the expectation that the stock will decline.
And when that expectation turns out to be wrong, the scramble to unwind those bets can sometimes create some of the fastest and most dramatic moves in the stock market.
For investors watching the remainder of 2026, CHTR, SMCI, MRNA, LULU and APA are five heavily shorted S&P 500 stocks worth keeping on the radar.
The next round of short-interest reports will be especially revealing because it should capture how traders repositioned after Moderna’s historic rally, Lululemon’s September selloff, and the continuing volatility in AI, communications, and energy stocks.
Disclaimer: This article is provided for news and informational purposes only. It does not constitute investment advice, financial advice, or a recommendation to buy, sell, or short any security. Short selling involves substantial risk, including the potential for losses greater than the original investment. Investors should conduct independent research and consult a qualified financial professional before making investment decisions.
