The shareholder registry is big, I think anyone on it can sell....

The shareholder registry is big, I think anyone on it can sell. I noticed a few individuals, that are not directors or ex directors, and they are totally in their right to take profit. 

Do you have a way to prove/disprove that it is an insider selling? All I can think of is to compare the size of the holdings since the last annual report, line by line, and hope to find the offloader. It is going to take time.