When I was a financial advisor, many of my clients worked for publicly traded companies and often had significant portions of their nest egg invested in their employers stock. Many companies have employee stock purchase plans (ESPP) that allow you to purchase stock (often at a discount) that accumulates similar to a 401k, but without diversification. A lot of large 401k plans also have company stock as an option for your 401k contributions. Combine these two methods of buying company stock with paternalistic companies with multi-generational histories and you end up with people who have 90+% of their net worth tied up in company stock.
My advice was always to sell off the company stock and diversify. Did no one learn anything from Enron? If you have too much of your world tied up in company stock and things go south, you have risk of losing your nest egg AND your job. It is riskier for you to own shares of your employer than it is for someone who doesn't also work there. Trying to convince people to sell company stock was always a difficult conversation, and I likened it to telling someone their kids were ugly. Holding the same stock for decades, people often would feel that the stock was partly responsible for their financial success, even if the stock had been a terrible performer.
My current employer is a large, publicly traded company, and I have made it a point to avoid buying any shares of stock. In addition to my concerns about diversification, because I work in finance I often have access to confidential information and so am only able to trade the stock during certain times (i.e., no transactions allowed near earning release dates or other major events).
From the time I was hired, our stock is up considerably (>3x), but so far this year hasn't really kept up with the rest of the market. I attended a leadership meeting this past week and while listening to the CEO and CFO speak, I found myself thinking "Wow, we're doing really well and our future is bright. Why don't I have any shares of our stock?" I came home and mentioned this to my wife thinking/hoping she'd tell me to snap out of it and don't do something stupid, but instead she just said "if you want to buy a few shares, just keep it small.
In the not too distant future, I could be in a position where a portion of my compensation is given in the form of company stock. At that point, what I decide to do with the stock will make a larger difference in my overall plan. My current strategy for stock received from my employer is to immediately sell at least half of any stock given, but to keep a small amount to show confidence in the work I am doing. Keeping stock that was granted to me somehow feels different than proactively going out and buying shares on my own though.
So here I stand…I'm probably only talking about a couple hundred dollars, which really isn't going to make a difference long term, it's more about the principle and not wanting to deviate from the advice I've given to so many other people.