You could only go after the Directors Insurance and that would...

You could only go after the Directors Insurance and that would require proof you invested based on representations made to you by them - not advice from anywhere else. As such it would only be those who had partaken in the IPO and the information provided prior to that. Then you would need to find a litigation fund lawyer group prepared to take it on and they would typically want a fee between 30-45%, so from my limited knowledge I'm not sure how'd you go