Last week, when I shared my portfolio in another article. I received comments privately from several people such as "50 stocks in your portfolio?!?! I think 30 should provide more than enough diversification", "Have you heard of Warren Buffet's 20 slot rules?", "Why are you holding so many different stocks?" etc. Well, there are a few reasons to this. 1) I have yet to devise or find a sound approach on deciding when to sell and what to sell. Thus I am currently only buying and not selling yet. I am working on it though. 2) The academic in me believes in the Modern Portfolio Theory which basically states that diversification reduces unsystematic risk. Although some books suggest that you will come close to optimal diversity with just 12 stocks, in theory, ......