Frontier Group Short Interest Rises to 51.8%
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 down 1.0%, the Nasdaq Composite was down 1.0%, the Russell 2000 index was up 0.2%, the Russell 2000 Growth ETFwas down 0.6%, and the Russell 2000 Value ETFwas flat in the five-day trading session range through March 19.SHORT INTEREST GAINERSOrtex-reported short interest on Frontier Group Holdingshad previously reached a multi-month high above 50% in the first week of December as the stock price had rallied. Short positioning had then retreated to track in a 35%-42% range over the second half of December and through January-February, though bears have been far more active over the past three weeks, coinciding with the start of the Iran campaign by U.S.-Israel forces. This week, short interest as a percentage of free float jumped from 44.4% to 51.8%, a 10-month high. Similarly, days-to-cover rose sharply from 7.2 to 8.3 despite the increase in trading volume. Shares of Frontier Group were down 6% in the five-day period ended Thursday, though the stock is now down 27% from the start of the Middle East tension as traders react to the double-whammy of higher oil price and heightened travel alertness impacting airline and cruise stocks.Ortex-reported short interest on WisdomTreehad receded from mid-February high levels around 26.5% toward 22% in the first two weeks of March, though this week, shorts as a percentage of free float nudged higher and back above 24% while days-to-cover on the stock rose from 7.8 to 8.6. The stock had been one of the best performing names among its small-cap peers in the asset management space and remains impressively higher double-digits year-to-date in spite of the headwinds encountered by private credit, though it was also down 8.5% in in the five-day period covered through Thursday and has now fallen 24% relative to its 2026 peak just two weeks ago.Ortex-reported short interest in Core Scientifichad tracked in a very narrow 25%-26% range from February 10 through March 10, though this week, traders have turned increasingly willing to underwrite a more bearish case for digital crypto mining names. Short interest as a percentage of free float climbed from 26.5% to 28.3% in the five-day period covered through Thursday even as the stock rose 1.5% against a decidedly negative broader market sentiment. Short positioning is now within two percentage points of its 2026 highs even though the stock is still up about 9% on the year.SHORT INTEREST DECLINERSThe oil shock related to the Middle East conflict has made energy the only market sector to generate gains this week, and this theme is also playing out across our short-interest screen, where every stock in the energy arena has seen its short positioning drastically reduced. Specifically, bearish exposure as a percentage of free float for Fluence Energyfell 10 percentage points to a two-month low of 19.5%, short interest on Northern Oil & Gasfell from 18.4% to a one-year low of 16.1%, while that of HighPeak Energyslipped from 28.4% to a one-month low of 25.3%. Shorts are heading for the exits as the path to an off-ramp from escalation around the Strait of Hormuz - sending oil prices up by about 50% in just three weeks - remains murky, and the performance of those stocks reflect the sharp supply-risk premium: Northern Oil has gained 3% and HighPeak soared by 20%, even though Fluence Energy slipped about 2% in the five-day period covered through Thursday.
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- Impact of Spirit's Collapse: Spirit Airlines ceased operations on May 2 after failing to secure a $500 million government bailout, intensifying competition among U.S. budget carriers; while its exit allows for fare increases, it does not resolve the long-standing cost pressures faced by the low-cost flight model.
- Competitor Strategies: Rivals like JetBlue and Frontier are targeting Spirit's market share, contending with the same surging fuel costs, with Frontier expecting a 3% to 5% increase in revenue per seat due to Spirit's exit, yet overall profitability remains constrained by rising operational costs.
- Fuel Cost Pressures: Avelo Airlines' CEO noted fuel prices surged from $2.56 to $4.71 per gallon, forcing a $20 fare increase; JetBlue and Frontier anticipate fuel costs rising over $100 million and $70 million to $83 million respectively this quarter, significantly impacting their profitability.
- Uncertain Market Outlook: While Allegiant Air reported a strong adjusted operating margin of 14.9%, the overall low-cost carrier sector faces dual challenges of high fuel costs and limited pricing power, leaving the future market outlook uncertain.
- Incident Overview: Frontier Airlines Flight 4345 struck a pedestrian during takeoff at Denver International Airport, resulting in a brief engine fire and runway closure for investigation, occurring at approximately 11:19 PM with 231 people on board.
- Emergency Response: The Denver Fire Department quickly extinguished the brief engine fire, and airport emergency teams promptly transported passengers to the terminal, ensuring their safety and demonstrating effective emergency response protocols.
- Investigation Underway: The airport has notified the National Transportation Safety Board, and Frontier Airlines stated it is coordinating with the airport and other safety authorities for the investigation, indicating the company's commitment to passenger safety and thoroughness in addressing the incident.
- Flight Details: The incident involved an Airbus A321 aircraft, originally scheduled to fly from Denver to Los Angeles, carrying 224 passengers and 7 crew members, which may negatively impact the airline's reputation and operations.
- Bankruptcy Warning: The bankruptcy of Spirit Airlines serves as a stark reminder that companies with high debt and low revenue face severe financial distress, and investors should be cautious about stocks emerging from bankruptcy due to their high risk of re-entering bankruptcy.
- Impact of Failed Merger: The collapse of JetBlue's merger with Spirit due to regulatory issues significantly increased the investment risk associated with Spirit, and investors should be wary of similar 'Hail Mary' attempts, as they often indicate deteriorating financial health.
- Leverage Risks: High jet fuel prices and excessive leverage contributed to Spirit's bankruptcy, highlighting the need for investors in transportation stocks to scrutinize balance sheets to avoid financial crises stemming from high debt levels.
- Industry Caution: Spirit's situation serves as a warning that rising fuel costs could jeopardize other airlines, particularly JetBlue and Frontier Group, prompting investors to remain vigilant against potential bankruptcy risks.
- Market Share Increase: The collapse of Spirit Airlines has instantly removed its market capacity, leading Frontier Airlines to anticipate a 3% to 5% uplift in revenue per available seat mile, significantly enhancing its competitive position in the airline industry.
- Optimistic Financial Outlook: Frontier expects unit revenue to rise over 20% in the second quarter, driven by strong demand and reduced competition, showcasing the company's robust recovery capabilities in the market.
- Stock Price Surge: Following the release of its first-quarter results, Frontier's shares rose more than 6% in afternoon trading, indicating increased investor confidence in its future growth prospects.
- Strategic Restructuring Impact: Frontier had previously planned to merge with Spirit Airlines, but the deal was thwarted by JetBlue's cash offer; Spirit's collapse now provides Frontier with an opportunity to reassess its market strategy.
- Revenue Growth Expectation: Frontier Airlines anticipates a 3% to 5% uplift in revenue per available seat mile due to Spirit Airlines' collapse, which removes competitive pressure from the market.
- Market Overlap Analysis: Prior to its shutdown, Spirit Airlines had a 35% overlap in seat capacity with Frontier, indicating a direct benefit for Frontier as it captures Spirit's market share.
- Quarterly Performance: Following the release of its quarterly results, Frontier's shares surged over 6%, reflecting strong market confidence, with expectations of more than a 20% increase in unit revenue for the second quarter.
- Changing Competitive Landscape: With Spirit's exit, Frontier and other airlines like JetBlue are actively expanding routes, further solidifying their market positions, particularly in Florida, where Spirit was previously based.
- Wider Loss: Frontier Group reported an adjusted loss per share of 30 cents for Q1, widening from 19 cents a year earlier, indicating a significant decline in profitability under cost pressures.
- Impact of Rising Fuel Prices: The surge in jet fuel prices has eroded Frontier's margins, leading to poor overall financial performance and highlighting the airline industry's high sensitivity to fuel cost fluctuations.
- Market Environment Challenges: In the highly competitive low-cost airline market, Frontier faces ongoing operational challenges, particularly against the backdrop of rising fuel prices, which may affect its future pricing strategies and market share.
- Financial Health Risks: As losses deepen, concerns about Frontier's financial health arise, potentially leading investors to question its long-term profitability, which could impact stock performance and financing capabilities.










