Senseonics Holdings, Inc. (NYSE American: SENS) saw its stock price plummet 6.21% in after-hours trading on Monday following the company's announcement of its preliminary third-quarter revenue and plans for a reverse stock split.

The medical technology company, which focuses on implantable continuous glucose monitoring systems, reported preliminary unaudited revenue of approximately $8.1 million for Q3 2025. While this represents a 91% increase compared to the same period last year, driven by 160% new patient growth in the U.S., investors appear to have reacted negatively to the news.

Adding to the market's concerns, Senseonics also revealed plans for a 1-for-20 reverse stock split, set to take effect on October 17, 2025. This move will reduce the number of outstanding common shares from about 816 million to approximately 41 million. Despite management's optimism about the company's performance and growth in patient numbers, the combination of these announcements seems to have triggered a sell-off in the after-hours session.