Sales increased after Megaupload shutdown. Haven't read the paper, but here's the relevant paragraph from the abstract:

Simply examining changes in sales after the shutdown would produce an inaccurate measure of its actual effect as sales are changing over time for a variety of reasons. Instead we exploit cross- country variation in pre-shutdown usage of Megaupload as a measure of treatment intensity. Controlling for country-specific trends and the Christmas holiday, we find no statistical relationship between Megaupload penetration and changes in digital sales prior to the shutdown. However, we find a statistically significant positive relationship between a country’s Megaupload penetration and its sales change after the shutdown, such that for each additional 1% pre-shutdown Megaupload penetration, the post-shutdown sales unit change was 2.5% to 3.8% higher, suggesting that these increases are a causal effect of the shutdown.

Of course, there's still the effect of "competition" with pirated downloads which spurred movie studios to offer online services in the first place, but it's interesting to see a seemingly high-quality study that shows the effect go in this direction. Most of the others show piracy increasing sales.