And a company that was worth 2 billion dollars with a decreasing revenue stream. As an ex employee of autonomy i can definitely say that HP made a very very big mistake.
2 billion? I think you are forgetting about their recent acquisition of Iron Mountain Digital. I would say the companies were worth 4-6 B. They still paid too much, but there is a big difference between paying 400% over value and paying 60% over value.
... Iron Mountain Digital was bought three months ago for $380M. If they were worth $2B before, they haven't doubled or tripled their worth because they spent $380M of their cash reserves.