Google processes requests from copyright holders and other reporting organisations to remove search results that link to material that allegedly infringes copyright under the Digital Millennium Copyright Act (DMCA).
The figures for February show that takedown requests have doubled in the last year. Over 76 million requests were received.
One reason for the increase may be because copyright holders are using algorithms to spot potential copyright infringements and automatically file takedown notices.
Sources: Google, Endgadget.