Vicor Corporation's stock plummeted 6.55% during intraday trading on Thursday, reflecting a sharp reversal from recent gains.

The decline is attributed to profit-taking activity following a significant post-earnings rally. The company's FY26Q1 results, released previously, exceeded market expectations for revenue and earnings per share, driven by better-than-forecast capacity expansion and the addition of Cerebras as a key customer. This positive news had fueled a substantial short-term price increase, leading investors to lock in profits.

Further downward pressure emerged from recent insider selling, with company directors reducing their holdings, which intensified market concerns about near-term selling supply and contributed to the stock's volatility.