Shares of Repligen (NASDAQ: RGEN) lost over 13% today, although there doesn't appear to be any company-specific news dragging the stock down. This simply appears to be good old-fashioned volatility caused by the stock's own success. Shares had posted a year-to-date gain of over 75% before today, and they're still up 54% since the beginning of the year after today's drop.
Investors have grown excited about the company's growth trajectory following solid first-half 2019 operating results and a major acquisition. Repligen even exited June with $209 million and appears to have at least doubled that total in the months since, suggesting it could still make another acquisition if the opportunity arises.
That said, shares are pretty expensive based on traditional stock metrics, which could explain the random sell off. As of 1:52 p.m. EDT, the stock had settled to an 11% loss.