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bluebird bio (BLUE) Short Interest Ratio & Short Volume

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bluebird bio Short Interest Overview

As of May 15, 2025, bluebird bio (BLUE) had a short interest of 281,500 shares sold short, representing 2.91% of the public float. This marks a -34.26% decrease in short interest since the prior report. The short interest ratio (days to cover) is 0.5, meaning it would take 0.5 days of the average trading volume of 807,956 shares to cover all short positions.

Current Short Interest
281,500 shares
Previous Short Interest
428,200 shares
Change Vs. Previous Month
-34.26%
Dollar Volume Sold Short
$1.40 million
Short Interest Ratio
0.5 Days to Cover
Last Record Date
May 15, 2025
Outstanding Shares
9,792,000 shares
Float Size
9,690,000 shares
Short Percent of Float
2.91%
Today's Trading Volume
0 shares
Average Trading Volume
807,956 shares
Today's Volume Vs. Average
0%
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Short Interest ChartDays to Cover ChartShort Percent of Float Chart

BLUE Short Interest Over Time

BLUE Days to Cover Over Time

BLUE Percentage of Float Shorted Over Time

bluebird bio Tesla Short Interest History & Recent Changes

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Report DateTotal Shares Sold ShortDollar Volume Sold ShortChange from Previous ReportPercentage of Float ShortedDays to CoverPrice on Report Date
5/15/2025281,500 shares $1.40 million -34.3%2.9%0.5 $4.97
4/30/2025428,200 shares $1.75 million -15.6%4.4%1.1 $4.08
4/15/2025507,400 shares $2.27 million -71.5%5.2%1.2 $4.47
3/31/20251,780,000 shares $8.69 million -3.8%18.4%4.3 $4.88
3/15/20251,850,000 shares $6.94 million -7.0%19.2%5.2 $3.75
2/28/20251,990,000 shares $8.12 million -26.8%20.6%4.2 $4.08
2/15/20252,720,000 shares $19.77 million +7.5%28.3%5.6 $7.27
1/31/20252,530,000 shares $19.61 million +4.6%26.3%6.3 $7.75
1/15/20252,420,000 shares $20.06 million +0.4%25.1%6.1 $8.29
12/31/20242,410,000 shares $20.10 million -6.6%25.0%5.9 $8.34
12/15/20242,580,000 shares $16.36 million -94.8%26.8%6.2 $6.34
11/30/202449,570,000 shares $20.08 million +13.6%N/A6.5 $0.41
11/15/202443,640,000 shares $14.00 million -8.5%N/A6.7 $0.32
10/31/202447,710,000 shares $22.14 million -3.5%N/A6.3 $0.46
10/15/202449,420,000 shares $23.78 million +0.9%N/A6.8 $0.48
9/30/202448,990,000 shares $25.45 million +1.2%N/A6.4 $0.52
9/15/202448,400,000 shares $29.32 million -2.0%N/A6.5 $0.61
8/31/202449,370,000 shares $27.72 million +20.0%N/A6.8 $0.56
8/15/202441,140,000 shares $29.02 million +32.2%N/A6.1 $0.71
7/31/202431,130,000 shares $36.11 million +1.2%N/A5.6 $1.16
7/15/202430,770,000 shares $40.62 million +0.2%N/A5 $1.32
6/30/202430,710,000 shares $30.22 million +4.2%N/A4.9 $0.98
6/15/202429,480,000 shares $28.29 million +1.2%N/A4.7 $0.96
5/31/202429,120,000 shares $26.31 million -7.9%N/A4.5 $0.90
5/15/202431,600,000 shares $33.81 million -0.8%N/A4 $1.07
4/30/202431,860,000 shares $28.26 million -2.3%N/A3.8 $0.89
4/15/202432,620,000 shares $33.60 million +9.7%N/A3.8 $1.03
3/31/202429,750,000 shares $38.08 million -12.6%N/A3.3 $1.28
3/15/202434,040,000 shares $48.34 million -0.3%N/A3.2 $1.42
2/29/202434,130,000 shares $47.44 million +19.4%N/A2.4 $1.39
2/15/202428,590,000 shares $30.88 million +4.0%N/A2.2 $1.08
1/31/202427,500,000 shares $28.05 million +3.5%N/A2.3 $1.02
1/15/202426,570,000 shares $39.86 million +10.3%N/A2.4 $1.50
12/31/202324,090,000 shares $33.24 million -5.4%N/A2.4 $1.38
12/15/202325,470,000 shares $83.29 million +16.6%N/A2.8 $3.27
11/30/202321,850,000 shares $83.47 million -2.9%N/A4.7 $3.82
11/15/202322,490,000 shares $73.99 million -8.5%N/A6.4 $3.29
10/31/202324,570,000 shares $72.48 million -0.4%N/A7 $2.95
10/15/202324,670,000 shares $65.62 million +2.3%N/A7 $2.66
9/30/202324,110,000 shares $73.29 million -17.0%N/A5.8 $3.04
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9/15/202329,040,000 shares $97.28 million +11.5%N/A7 $3.35
8/31/202326,040,000 shares $98.17 million -1.6%N/A6.3 $3.77
8/15/202326,450,000 shares $95.75 million -8.3%N/A6.2 $3.62
7/31/202328,840,000 shares $113.34 million +13.7%N/A6.6 $3.93
7/15/202325,360,000 shares $76.84 million -21.5%N/A5.8 $3.03
6/30/202332,300,000 shares $106.27 million +6.1%N/A8.1 $3.29
6/15/202330,440,000 shares $121.46 million +23.0%N/A6.8 $3.99
5/31/202324,740,000 shares $82.88 million +5.3%N/A5.2 $3.35
5/15/202323,490,000 shares $96.78 million -0.3%N/A5 $4.12
4/30/202323,550,000 shares $102.44 million -0.8%N/A5.3 $4.35
4/15/202323,740,000 shares $74.07 million -10.3%N/A5.5 $3.12
3/31/202326,450,000 shares $84.11 million +29.0%N/A6.1 $3.18
3/15/202320,510,000 shares $95.37 million +12.2%N/A5.4 $4.65
2/28/202318,280,000 shares $95.06 million +5.5%N/A5.4 $5.20
2/15/202317,320,000 shares $102.88 million +0.2%N/A5.1 $5.94
1/31/202317,290,000 shares $109.79 million -6.3%N/A4.7 $6.35
1/15/202318,450,000 shares $145.57 million +1.2%N/A4.9 $7.89
12/30/202218,240,000 shares $126.22 million -1.1%N/A5.3 $6.92
12/15/202218,450,000 shares $143.54 million +1.0%N/A4.6 $7.78
11/30/202218,270,000 shares $142.32 million -5.2%N/A3.3 $7.79
11/15/202219,270,000 shares $148.38 million -14.5%N/A3.2 $7.70
10/31/202222,540,000 shares $141.33 million +0.5%N/A3.1 $6.27
10/15/202222,440,000 shares $143.39 million -1.2%N/A2.9 $6.39
9/30/202222,710,000 shares $143.75 million +13.0%N/A2.9 $6.33
9/15/202220,100,000 shares $142.51 million +1.8%N/A2.4 $7.09
8/31/202219,740,000 shares $115.28 million +19.9%N/A2 $5.84
8/15/202216,460,000 shares $112.42 million +8.4%N/A1.8 $6.83
7/31/202215,190,000 shares $61.52 million +13.3%N/A2 $4.05
7/15/202213,410,000 shares $64.50 million -11.1%N/A2 $4.81
6/30/202215,090,000 shares $62.47 million -13.8%N/A2.3 $4.14
6/15/202217,510,000 shares $60.93 million +39.0%32.1%3.2 $3.48
5/31/202212,600,000 shares $40.32 million +1.9%N/A5.2 $3.20
5/15/202212,370,000 shares $44.16 million +1.8%N/A5.3 $3.57
4/30/202212,150,000 shares $44.10 million +6.6%N/A5.4 $3.63
4/15/202211,400,000 shares $51.76 million -0.7%N/A4.8 $4.54
3/31/202211,480,000 shares $55.68 million +43.7%N/A4.8 $4.85
3/15/20227,990,000 shares $35.72 million +9.2%N/A3.1 $4.47
2/28/20227,320,000 shares $44.21 million +2.0%N/A3.1 $6.04
2/15/20227,180,000 shares $48.68 million +3.2%N/A3.1 $6.78
1/31/20226,960,000 shares $54.91 million +1.0%N/A2.8 $7.89
1/15/20226,890,000 shares $60.15 million +19.0%N/A2.9 $8.73
12/31/20215,790,000 shares $57.84 million +4.3%N/A2.8 $9.99
12/15/20215,550,000 shares $52.78 million -3.3%N/A2.8 $9.51
11/30/20215,740,000 shares $58.03 million +6.3%N/A3.9 $10.11
11/15/20215,400,000 shares $61.99 million +5.9%N/A3.8 $11.48
10/29/20215,100,000 shares $119.39 million -11.5%7.8%3.9 $23.41
10/15/20215,760,000 shares $120.38 million -0.2%8.8%4.9 $20.90
9/30/20215,770,000 shares $110.26 million +10.5%8.8%5.1 $19.11
9/15/20215,220,000 shares $92.92 million -8.6%7.9%3.8 $17.80
8/31/20215,710,000 shares $104.49 million -9.7%8.7%4 $18.30
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8/13/20216,320,000 shares $116.73 million +1.1%9.6%4.5 $18.47
7/30/20216,250,000 shares $158.81 million +6.5%9.5%4.4 $25.41
7/15/20215,870,000 shares $161.60 million -7.3%8.9%4.7 $27.53
6/30/20216,330,000 shares $202.43 million +18.3%9.6%4.8 $31.98
6/15/20215,350,000 shares $175.64 million +4.7%8.1%4.1 $32.83
5/28/20215,110,000 shares $159.02 million -13.4%7.7%3.8 $31.12

BLUE Short Interest - Frequently Asked Questions

Short interest is the volume of bluebird bio shares that have been sold short but have not yet been covered or closed out. As of May 15th, traders have sold 281,500 shares of BLUE short. 2.91% of bluebird bio's shares are currently sold short. Learn More on bluebird bio's 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. BLUE shares currently have a short interest ratio of 0.5. Learn More on bluebird bio's short interest ratio.

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. 2.91% of bluebird bio's floating shares are currently sold short.

bluebird bio saw a decline in short interest in May. As of May 15th, there was short interest totaling 281,500 shares, a decline of 34.3% from the previous total of 428,200 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.

bluebird bio currently has issued a total of 9,792,000 shares. Some of bluebird bio's outstanding shares are available for trading, while others are subject to various restrictions. The public float, also referred to as floating shares or "the float", are shares that publicly owned, unrestricted and available to trade on the open market. bluebird bio currently has a public float of 9,690,000 shares.

2.91% of bluebird bio's shares are currently sold short. Here is how the short interest of companies in the industry of "pharmaceutical products" compare to bluebird bio: Lifecore Biomedical, Inc. (10.69%), Precision BioSciences, Inc. (5.64%), Caribou Biosciences, Inc. (7.85%), Corbus Pharmaceuticals Holdings, Inc. (8.23%), Acumen Pharmaceuticals, Inc. (2.50%), Tiziana Life Sciences Ltd (1.78%), Korro Bio, Inc. (8.12%), Tonix Pharmaceuticals Holding Corp. (19.85%), Molecular Partners AG Sponsored ADR (0.03%), ProQR Therapeutics N.V. (0.88%),

As of the most recent reporting period, the following stocks had the largest short interest positions: Invesco QQQ ($29.20 billion), Strategy Inc ($10.88 billion), iShares 20+ Year Treasury Bond ETF ($10.04 billion), Capital One Financial Corporation ($5.51 billion), Charter Communications, Inc. ($5.00 billion), Super Micro Computer, Inc. ($4.43 billion), Apollo Global Management Inc. ($4.02 billion), Hims & Hers Health, Inc. ($3.65 billion), VanEck Semiconductor ETF ($3.27 billion), and Coinbase Global, Inc. ($3.10 billion). View all of the most shorted stocks.

Short selling BLUE is an investing strategy that aims to generate trading profit from bluebird bio as its price is falling. 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 bluebird bio 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 BLUE, 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 BLUE, twice per month. The most recent reporting period available is May, 15 2025.

Understanding short interest metrics can help you assess how traders are positioning around a stock like BLUE:

  • Shares Sold Short: The total number of shares that have been sold by short sellers but have not yet been covered or closed out. A high number may indicate bearish sentiment.
  • Short Float: The percentage of a company’s publicly available shares (or "float") that are sold short. A higher short float suggests a greater portion of the stock is being bet against.
  • Days to Cover (Short Interest Ratio): This estimates how many days it would take short sellers to cover their positions, based on average daily trading volume. Higher values can signal potential for a short squeeze if buying pressure increases.

These metrics are often used by traders to gauge sentiment, volatility risk, and the potential for price movements based on short covering activity.


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This page (NASDAQ:BLUE) was last updated on 5/15/2026 by MarketBeat.com Staff.
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