PRTA Short Volume

Prothena Corporation plc (PRTA) operates in the Healthcare sector, specifically the Biotechnology industry, with a market capitalization near $502.6M, listed on NASDAQ, employing roughly 163 people, carrying a beta of -0.23 to the broader market. Prothena Corporation plc, a late-stage clinical company, focuses on discovery and development of novel therapies for life-threatening diseases in the United States. Led by Gene G. Kinney, public since 2012-12-18.

Short volume measures the number of shares sold short on a given day as reported by FINRA. Tracking short volume relative to total volume helps identify unusual bearish sentiment or short-squeeze potential.

Latest Date
2026-05-15
Short Volume
78.2K
Total Volume
131.3K
Short %
59.53%
30-Day Avg Short %
63.46%

Showing 30 days of FINRA short volume data for Prothena Corporation plc.

Learn how short volume is reported and how to read the data →

Frequently asked PRTA short volume questions

What is the daily PRTA short volume?
As of May 15, 2026, Prothena Corporation plc (PRTA) short volume is 78.2K shares against 131.3K total reported volume, or 59.53% short-side. Short volume measures shares sold short during the day; it is flow, not inventory.
How is PRTA short volume reported?
FINRA publishes the Daily Short Sale Volume File for trades reported to FINRA TRFs and the FINRA/Nasdaq ADF on a T+1 basis. The headline figure is the count of shares that printed at the short-sale or short-exempt tick across all reporting venues for the symbol; each exchange separately publishes its own daily short-sale data file.
What does PRTA short volume tell options traders?
Daily short-sale flow is one input that helps disambiguate dealer-hedging activity from directional bear flow when the chain shows fresh customer call inventory. It is not a clean MM-only proxy: the headline number mixes directional shorting, options-MM delta-hedging, ETF-creation arbitrage, and convertible-arb hedging. Cross-check against gamma-exposure and OI changes for a cleaner read.