Alnylam Pharmaceuticals (ALNY) Short Interest Ratio & Short Volume

Short interest is the volume of Alnylam Pharmaceuticals shares that have been sold short but have not yet been covered or closed out. As of August 31st, traders have sold 3,970,000 shares of ALNY short. 3.07% of Alnylam Pharmaceuticals' shares are currently sold short. Learn More on Alnylam Pharmaceuticals' current short interest.

The short interest ratio, also known as the "days to cover ratio", is calculated by dividing the number of shares of a stock sold short divided by its average trading volume. A short interest ratio ranging between 1 and 4 generally indicates strong positive sentiment about a stock and a lack of short sellers. A short interest ratio of 10 or greater indicates strong pessimism about a stock. ALNY shares currently have a short interest ratio of 4.0. Learn More on Alnylam Pharmaceuticals's short interest ratio.

As of the most recent reporting period, the following institutional investors, funds, and major shareholders have reported short positions of Alnylam Pharmaceuticals: LMR Partners LLP, Group One Trading LLC, 683 Capital Management LLC, Jane Street Group LLC, Volterra Technologies LP, Diadema Partners LP, Qube Research & Technologies Ltd, Walleye Capital LLC, Walleye Trading LLC, Arrowpoint Investment Partners Singapore Pte. Ltd., JPMorgan Chase & Co., Persistent Asset Partners Ltd, Garda Capital Partners LP, Mirae Asset Securities USA Inc., Portman Square Capital LLP, and Twin Tree Management LP. These positions are disclosed in Form 13F filings with the Securities and Exchange Commission.

Companies that have a short interest as a percentage of float below 10% indicates positive investor sentiment and few short sellers. Stocks with a short interest percentage above 10% is considered high, suggesting some investors are pessimistic about the stock. Companies with a short interest percentage of 20% or more indicates widespread negative sentiment. 3.07% of Alnylam Pharmaceuticals' floating shares are currently sold short.

Alnylam Pharmaceuticals saw a increase in short interest in August. As of August 31st, there was short interest totaling 3,970,000 shares, an increase of 15.7% from the previous total of 3,430,000 shares. Changes in short volume can be used to identify positive and negative investor sentiment. Investors that short sell a stock are betting that its price will decline in the future. An increase in short sale volume suggests bearish (negative) sentiment among investors. A decrease on short sale volume suggests bullish (positive) sentiment.

3.07% of Alnylam Pharmaceuticals' shares are currently sold short. Here is how the short interest of companies in the industry of "biotechnology" compare to Alnylam Pharmaceuticals: Amgen Inc. (2.20%), Gilead Sciences, Inc. (1.42%), Vertex Pharmaceuticals Incorporated (1.42%), Regeneron Pharmaceuticals, Inc. (2.77%), Biogen Inc. (3.23%), United Therapeutics Corporation (6.17%), Incyte Corporation (3.89%), Neurocrine Biosciences, Inc. (4.37%), Exelixis, Inc. (6.76%), BioMarin Pharmaceutical Inc. (3.13%),

As of the most recent reporting period, the following stocks had the largest short interest positions: SPDR S&P 500 ETF Trust ($73.23 billion), Invesco QQQ ($29.52 billion), iShares Russell 2000 ETF ($20.82 billion), iShares 20+ Year Treasury Bond ETF ($10.76 billion), Palo Alto Networks, Inc. ($9.37 billion), Strategy Inc ($7.58 billion), Invesco S&P 500 Equal Weight ETF ($6.78 billion), SPDR S&P Biotech ETF ($6.72 billion), AppLovin Corporation ($6.37 billion), and iShares iBoxx $ Investment Grade Corporate Bond ETF ($6.29 billion). View all of the most shorted stocks.

Short selling ALNY is an investing strategy that aims to generate trading profit from Alnylam Pharmaceuticals as its price is falling. ALNY shares are trading up $5.36 today. To short a stock, an investor borrows shares, sells them and buys the shares back on the public market later to return it to the lender. Short sellers are betting that a stock will decline in price. If the stock does drop after selling, the short seller buys it back at a lower price and returns it to the lender. The difference between the sell price and the buy price is the trader's profit.

A short squeeze for Alnylam Pharmaceuticals occurs when it has a large amount of short interest and its stock appreciates in price. This forces short sellers to cover their short interest positions by buying actual shares of ALNY, which in turn drives the price of the stock up even further.

Short interest is typically published by a stock exchange once per month. However, NASDAQ publishes a report for U.S. stocks, including ALNY, twice per month. The most recent reporting period available is August, 31 2025.