I recently came across an interesting article in the Financial Planning magazine about the risks of holding on to concentrated stock positions. It talks about how we tend to hold on to large holdings of a single stock for a variety of reasons, including a reluctance to sell a stock because it was inherited or keeping a stock because he or she worked for the company for a long time. Without a doubt, clients underestimate the risks of owning a substantial amount of a single stock.
The article does a good job of brainstorming some of the ways in which we can strategically reduce our exposure to a single concentrated position. It is a good read. If you have any concentrated stock or know that you could potentially have a concentrated position in the future, I recommend reading this article.