OptiNose shareholders are down 18% for the year, but the market itself is up 25%. Even the share prices of good stocks drop sometimes, but we want to see improvements in the fundamental metrics of a business, before getting too interested. Unfortunately, longer term shareholders are suffering worse, given the loss of 13% doled out over the last five years. We would want clear information suggesting the company will grow, before taking the view that the share price will stabilize. It's always interesting to track share price performance over the longer term. But to understand OptiNose better, we need to consider many other factors. Take risks, for example - OptiNose has 3 warning signs (and 1 which can't be ignored) we think you should know about.