Alex Singleton at Samizdata points to research suggesting that the presence of pharmaceutical patent laws actually suppress pharmaceutical research instead of fostering it. Patent laws also allow a few large companies to dominate an industry, to the detriment of smaller ones.
The idea of a patent is dependent on the principle that governments can restrict the legitimate economic activity of private citizens by fiat. The sole justification for doing so would be if, by guaranteeing that inventors may profit first from their work, patents promoted overall innovation.
Just as often, patents artificially restrain engineers from incorporating new advances into established technologies for arbitrary lengths of time, and put up barriers to cooperation. Therefore, if the premise by which patents are justified turns out to be flawed, then there is a compelling need for patent law to be radically reworked, if not repealed entirely.
As they say, information wants to be free.