Just a simple question that came to mind, but most penny stocks especially in the otc and pink sheet tend to get promoted a lot by ads and spam is it the same for small cap stocks on nasdaq exchange and others like it? or are stocks on that exchange promoted differently?
The penny/pink sheet stocks you tend to see promoted are the ones a) with small public floats or, b) they are thinly traded. This means that any appreciable change in buy/sell volume will have an outsized effect on the stock's share price, even when the underlying fundamentals are not so great. Promoters are frequently paid based on how much they can move a stock's price, but such moves are not long-lasting. They peter out when the trading volumes return to more normal ranges for the stock because all of the hype has died out.
There are some small-cap NASDAQ stocks which can be susceptible to promotion for the same reason -- they have small floats and/or are thinly traded. Once someone figures out the best targets, they'll accumulate a position and then start posting all kinds of "news" on the web in an effort to drum up interest so they can sell off their position into the buying that follows.
The biggest problem with penny/pink sheet stocks is that they frequently fail to publish reliable financial statements, and their ownership is of a dubious nature. In the past, these types of stocks have been targeted by organized crime syndicates, which ran their own "pump and dump" operations as a way to make relatively easy money. This may still be true to some extent today.
Be wary of investing in any publicly-traded firm that has to use promoters to drum up investor interest, because it can be a serious red flag. Even if it means missing out on a short-term opportunity, research the company before investing. Read its financials, understand how it has behaved through its trading history, learn about the products/services it is selling. Do your homework. Otherwise you are doing the investing equivalent of taking your money and lighting it on fire.
Remember, there's a good reason these companies are trading as penny/pink sheet stocks, and it generally has nothing to do with the notion (the promoters will tell you) that somehow the "market has missed out on this amazing opportunity." Pump and dump schemes, which lie at the heart of almost all stock promotion, rely on convincing you, the investor, that you're smart enough to see what others haven't.
I hope this helps.