Some data here: http://books.google.com/books?id=iYuh-gfnwb0C&pg=PA361&lpg=PA361&dq=insider+buying+statistics&source=bl&ots=cs3Kv8Id4q&sig=T5F5gPM_kYKVUx6AtbZA

Some data here: http://books.google.com/books?id=iYuh-gfnwb0C&pg=PA361&lpg=PA361&dq=insider+buying+statistics&source=bl&ots=cs3Kv8Id4q&sig=T5F5gPM_kYKVUx6AtbZALn970uA&hl=en&ei=PD_WTOnNDJG4sQOKxoGNCw&sa=X&oi=book_result&ct=result&resnum=2&ved=0CCAQ6AEwATgK#v=onepage&q=insider%20buying%20statistics&f=false http://books.google.com/books?id=iYuh-gfnwb0C&pg=PA361&#... Basically, it seems that extreme insider buying is a very good sign for the market as a whole, but it's fairly rare. (31.7% returns in one three month period w/ insider buying signal, vs. avg. 4.2% returns in 75 3-month periods w/ insider selling signal) In terms of individual stocks, it seems that the predictive power of insider buying as a metric is best when mixed with taking into account the company's dividend yield, and they claim that this gives you a 6.2% edge.