...while building a long position? Not even sure the question really makes sense, but not familiar with all the ways shorts are used. I've seen a weird short by Voleon, on a stock which is about to release a stream of sales and partnerships news. Really looks like it will be pretty big over the next few months. Either way it's a pretty risky stock to short, has too much cash coming in and growing monthly. Now I've noticed a hedge fund recently started shorting it and even increased the short yesterday as the price got higher. I know why many shorts are taken out - bad company, likely to have share price fall, or hedging generally in a market with a long/short strategy. But what about shorting companies that look to have excellent short to medium term growth. Why not wait for those to really max out their share price, then go short. What tactical reasons could there to use a short?