Optimal Finance Daily · Wednesday, July 15, 2026
Erik Carter identifies over-concentration in company stock as a significant investment mistake, often stemming from 401(k) allocations or unexercised stock options. He advises that having more than 10-15% of a portfolio in a single stock is dangerous, especially employer stock, due to the risk of total loss and the existing tie to one's job.
“One of the biggest investment mistakes I see is having too much in company stock.”
“Either way, having more than 10 to 15% of your portfolio in any one stock is extremely dangerous because unlike the market as a whole, an individual stock can go to zero and never recover.”
“It's even more risky when it's your employer's stock because your job is already tied to your company.”