Short bets on S&P 500 Healthcare sector eases in August; MRNA stays most shorted stock

[Stock Market Health Care Index. Trading screen with a sector index for Health Care, quotes, charts and changes.]
Torsten Asmus

The average short interest in the S&P 500 Healthcare sector (NYSEARCA:XLV [https://seekingalpha.com/symbol/XLV]) decreased slightly in August, indicating a minor softening of negative sentiment among investors. The average short interest for the sector was 1.89%, down from 1.95% the previous month. Despite this overall trend, Moderna (NASDAQ:MRNA [https://seekingalpha.com/symbol/MRNA]) remains the most heavily shorted stock in the sector.

Despite its 12.12% weighting in the S&P 500, the healthcare sector has underperformed the broader market this year. The Health Care Select Sector SPDR Fund ETF (NYSEARCA:XLV [https://seekingalpha.com/symbol/XLV]) has seen a modest rise of 0.39% year-to-date, a notable contrast to the S&P 500's 11.95% gain over the same period.

STOCKS WITH THE LARGEST AND LEAST SHORT POSITIONS

_Ranked by short interest as a percentage of shares float_

[Seeking Alpha]
Seeking Alpha (Seeking Alpha)

Moderna (NASDAQ:MRNA [https://seekingalpha.com/symbol/MRNA]) remained the most heavily shorted stock in the sector, with short interest at 17.42% of its float, a decrease from 18.29% the previous month. Despite the high short position, Seeking Alpha's Quant Rating gives the stock a "Hold" with a score of 2.74 out of 5.

"Moderna (NASDAQ:MRNA [https://seekingalpha.com/symbol/MRNA]) reported a sharp decline in revenue for Q2 2025, earning only $0.1 billion and experiencing a net loss of $0.8 billion. The stock has dropped over 70% in the past year due to investor concerns regarding ongoing losses and reduced demand for COVID vaccines. Despite recent product approval, the company anticipates significant losses in 2025. However, with a strong cash position of $7.5 billion, a revenue recovery is possible through opportunities in vaccines and oncology," a Seeking Alpha analyst wrote [https://seekingalpha.com/article/4808323-moderna-q2-earnings-review-downsizing-triggers-selloff-but-im-long-term-bullish].

The second-most shorted stock in August was DaVita (NYSE:DVA [https://seekingalpha.com/symbol/DVA]) at 9.46%, while Henry Schein (NASDAQ:HSIC [https://seekingalpha.com/symbol/HSIC]) was third at 8.23%.

On the other hand, several major companies had very low short interest, including Johnson & Johnson (NYSE:JNJ [https://seekingalpha.com/symbol/JNJ]) at 0.78%, STERIS plc (NYSE:STE [https://seekingalpha.com/symbol/STE]) at 0.82%, and AbbVie (NYSE:ABBV [https://seekingalpha.com/symbol/ABBV]) at 0.87%.

INDUSTRY ANALYSIS

_Average short interest as a percentage of floating shares_

[Seeking Alpha]
Seeking Alpha (Seeking Alpha)

For the 17th month in a row, the biotechnology industry was the most shorted in the healthcare sector, despite short interest ticking down to 2.69% from 2.99% in July. The healthcare provider and services sectors also saw a notable increase in short interest, rising to the second-highest level at 2.41%.

In contrast, the pharmaceuticals' industry had the lowest short interest, which fell to 1.55% for the month.

RELATED ETFS: Health Care Select Sector SPDR Fund (NYSEARCA:XLV [https://seekingalpha.com/symbol/XLV]), SPDR S&P Pharmaceuticals ETF (NYSEARCA:XPH [https://seekingalpha.com/symbol/XPH]), VanEck Pharmaceutical ETF (NASDAQ:PPH [https://seekingalpha.com/symbol/PPH]), iShares Nasdaq Biotechnology ETF (NASDAQ:IBB [https://seekingalpha.com/symbol/IBB]), iShares U.S. Pharmaceuticals ETF (NYSEARCA:IHE [https://seekingalpha.com/symbol/IHE]), and Invesco Nasdaq Biotechnology ETF (NASDAQ:IBBQ [https://seekingalpha.com/symbol/IBBQ]).

MORE ON THE HEALTH CARE SELECT SECTOR SPDR® FUND ETF

* XLV: Market Overreaction Could Drive Double Digit Shareholder Yield [https://seekingalpha.com/article/4822422-xlv-market-overreaction-could-drive-double-digit-shareholder-yield]
* XLV Vs. IHE: Will Pharmaceuticals Outperform Healthcare? [https://seekingalpha.com/article/4817656-xlv-vs-ihe-will-pharmaceuticals-outperform-healthcare]
* XLV: Life Expectancy, Patents, And A Positive Outlook Will Pave The Way [https://seekingalpha.com/article/4801594-xlv-life-expectancy-patents-and-a-positive-outlook-will-pave-the-way]
* Notable healthcare headlines for the week: UnitedHealth, Novo Nordisk and Novartis in focus [https://seekingalpha.com/news/4494597-notable-healthcare-headlines-for-the-week-novo-nordisk-novartis-and-unitedhealth-in-focus]
* Tariff threats will be ongoing; this is how discretionary, industrials, and healthcare companies are mitigating [https://seekingalpha.com/news/4493088-tariff-threats-will-be-ongoing-this-is-how-discretionary-industrials-and-healthcare-companies-are-mitigating]