Vicor Corporation reported a 27.9% jump in short interest between mid-December and year-end, with total shares sold short rising from 1,205,653 on December 15 to 1,542,290 by December 31. This elevated short interest now represents 5.0% of the company’s float. With an average daily trading volume of 471,568 shares, the days-to-cover ratio sits at 3.3 days, underscoring increased bearish positioning and potential for short-squeeze dynamics among active traders.

Over the past quarter, key Vicor insiders have reduced their holdings substantially. Vice President Claudio Tuozzolo sold 14,637 shares in late October, trimming his stake by more than 30%, while CAO Quentin A. Fendelet disposed of 16,561 shares on the same date. Combined insider sales over the last ninety days total 278,345 shares. Despite these transactions, insiders retain a significant 31.3% ownership stake, indicating continued alignment with long-term company prospects.

Institutional investors adjusted positions in Vicor during the third and fourth quarters. PNC Financial Services Group increased its stake by 13.7%, acquiring an additional 136 shares, while Nisa Investment Advisors boosted its holding by 53.4% with a 210-share purchase. Amalgamated Bank added 224 shares (3.4% increase) and GAMMA Investing expanded by 19.8% through a 259-share acquisition in Q4. Creative Planning also raised its position by 5.4% via 281 new shares. Collectively, hedge funds and other institutions now own 47.45% of the company’s stock, reflecting steady confidence among professional investors.