I doubt that...

I can't remember the name of the company, but I remember seing a company that had over 10% of another company... they then did an hostile takeover... then when they find out they had more then 10% of the holding with no declaration, the hostile takeover didn't take place, and the company was sued (I don,t know how to write it sorry!) by the company they were trying to takeover (and automaticly by all shareholders)

Maybe you are right, but I' ve seen numerous case of fund managers buying high stakes in company and they had to declare on top of 10%... they also have different levels where they have to declare (like 15%... 20% etc, but I don't know what these levels are)