Tempus AI Short Interest Soars to 30.5%

Welcome to this week's installment of "The Short Interest Report" - The Fly's weekly recap of short interest trends among some of the most widely followed high-short-float stocks. Using the data from our partner, which utilizes the latest information from stock lenders to estimate short interest changes for thousands of publicly traded companies, this report will screen for some of biggest changes in short interest as a percentage of free float and days-to-cover ratios while also considering the short interest data on some of the more volatile and heavier-traded names of the week. Based on the availability of data from Ortex, the report tracks the trading period that covers prior Friday through Thursday of this week, excluding holidays. As a basis of comparison for stocks discussed below, the S&P 500 index was up 1.6%, the Nasdaq Composite was up 2.4%, the Russell 2000 index was up 3.3%, the Russell 2000 Growth ETFwas up 4.0% and the Russell 2000 Value ETFwas up 3.3% in the four-day trading session range through May 28.SHORT INTEREST GAINERSOrtex-reported short interest on Tempus AIhad tracked in the 21% to 25% range since the first week of March before jumping this week from 23.3% to 30.5% - the highest level on record. Days-to-cover on the stock also hit its highest print, rising from 4.8 to 6.5, with the bulk of the increase coming on Thursday in spite of the spike in trading volume. Overall, the stock was up 10.3% in the four-day period covered this week, with the rally catalyzed by the announced expansion of indications to the company's Next platform ahead of the 2026 American Society of Clinical Oncology Annual Meeting, prior to Friday's 2% slip. Year-to-date, TempusAI is now down about 15%.Ortex-reported short interest in Figmahad broken out into double-digits in February and continued to rise gradually over the past several months. Over the past month, however, while investors have seemingly gained conviction that the pressure over the post-IPO period may have subsided as the stock price rallied, the accumulation on the bearish side has also accelerated. This week, short interest as a percentage of free float jumped five percentage points to 30.8% - the highest level on record. Days-to-cover on the name similarly turned up, in spite of the spike in trading volume seen after the company's Q1 results in mid-May, rising from 3.3 to 4.2, also a record high. Shares of Figma were up about 9% in the four-day period covered through Thursday. Still, even after Friday's additional 9% jump, the stock remains down by about 32% year-to-date.As discussed here two weeks ago, short positions in Rumblesaw a washout over the last week of April and into the first week of May as shares rebounded from March lows with a rally of about 75%. With the bounce in the stock price accelerating over the past several sessions however, bears are more emboldened by the perception of an overly aggressive valuation. This week, according to Ortex data, short interest as a percentage of free float on Rumble jumped from 20.1% to 27.9% - the highest level in over 14 months - while days-to-cover on the name rose from 8.6 to 9.1. The stock was up 28% in the four-day period covered and has now gained 45% year to date, though shares are giving in to some profit taking on Friday with a 3% decline.SHORT INTEREST DECLINERSOrtex-reported short interest on Bobs Discount Furniturepeaked at a record-high of 28% on May 15 as bears positioned to fade the two-day rally of over 35% following the company's Q1 earnings beat on May 7. While the post-earnings bullishness receded over the subsequent two-week period however, the stock has bounced back this week with no constructive news flow, driving a short squeeze amid the over-extended bearishness. In the four-day period covered through Thursday, short interest as a percentage of free float on Bob's Discount was down from 24.6% to 20.6%, a 7-week low, with days-to-cover on the name also slipping from 5.8 to 4.9. In that time span, the stock was also up 16%, though shares of the discount furniture retailer are still down 19% year to date and down 20% from its IPO listing price in February.