I generate new investing ideas mostly through reading investment write-ups online, talking to other investors, occasionally going through screens of companies that meet some high-level criteria I look for, and general learning (like reading books and news) that sometimes leads to an idea. I like getting ideas from others (via investing websites, blogs, and friends of mine) because it’s a quick way to get an overview of the business and industry. Thus, my research doesn’t have to start from scratch. Between investing websites and blogs that I follow, I look at several hundred investment write-ups per year.
Depending on how well I know the industry, my research for a new company generally takes anywhere from a few weeks to several months. Thus, in an entire year I only have time to get to know a handful of companies really well. This forces me to be very picky on what companies I spend time researching. I want to know a small number of high-quality companies very well, as opposed to knowing less about hundreds or thousands of companies.