RE: Rule of Thumb?2 ways of looking at it. There has to be a buyer to consumate the sale. All buyers believe they are going to make money.
Anonymous investors usually have millions of shares and are the only ones that professionals can go to get a large quantity of shares in one deal without disrupting the market.
Often Anonymous investors in a young stock like this were part of the underwriting team so in a sense they have a responsibility to distribute the stock - and from their end - make money at the same time. Yes, it is difficult to distinguish whether a stock is being distributed or sold for negative reasons but one has to keep an open mind to "distribution" and often that is a tip to buy because some investment professional at the other end is also buying.
It's a great time to get in if you have a time period of 3-5 years.