Avis Budget Group shares jumped up to 19% in pre‑market trading, marking a fourth straight session of gains.
Short interest surged to about 62% of free float (S3 Partners) and 54% per Nasdaq, with 7.3 days‑to‑cover.
Barclays downgraded the stock to underweight, citing a 71% concentration of outright ownership and over‑100% economic interest from swaps.
Over the past 30 days the share price rose more than 500%, and is up 374% year‑to‑date.