Many stocks have risen in value in the wake of a positive news on the COVID-19 front.
But shares in a company that's profited from the pandemic have gone in the opposite direction.
In the first hour of trading, Etsy stock was down 12.39 percent, dropping to US$128.15 on NASDAQ.
This came after Pfizer and Biontech announced that their COVID-19 vaccine candidate was more than 90 percent effective in a phase three study.
Etsy is an online global marketplace for creative goods ranging from handcrafted pieces to vintage items.
Many of its sellers work from home. And it's provided an alternative to bricks-and-mortar retail, which has been hit hard by the coronavirus outbreak.
Another major online retailer, Amazon, has also seen its stock price slide this morning, though not nearly as far as has Etsy's.
As of this writing, Amazon is down 1.41 percent at US$3,264.60 on NASDAQ.