‘Information (or data) wants to be free’ – so goes the mantra of hackers and data activists. In the past this meant computer geeks hacking into secure private networks to fulfill their own curiosity or liberate secret knowledge. Today, voluntary ‘data liberation’, as practiced by governments and corporations, is relatively commonplace and semiorganized groups with data freedom agendas, such as Wikileaks and Anonymous, have entered the mainstream consciousness. For me, it feels increasingly challenging to delineate the margins where free data is good or bad. A highly networked, mobile-enabled popular uprising is considered a ‘revolution’ when it’s against an oppressive regime, but considered a ‘menace’ when it is a disenfranchised mob rioting in a western democracy. Bravely recorded videos of civilians attacked by autocratic regime military forces are essential in prosecuting crimes against humanity, but videos leaked from within a democratic military are a ‘threat to national security’. So while data itself may want to be free, we don’t always want it to be. And so, to clinical trials. From a societal perspective, the requirement for any trials conducted in the USA to register on ClinicalTrials.gov can only be a good thing in preventing past sins, such as suppressing negative trials or changing end points. As the US government makes this data open, it also allows repurposing. For instance, PatientsLikeMe imports the complete dataset from ClinicalTrials.gov every night to let our membership know (free of charge) about the 30,000+ active trials for which they may be eligible. So far, so good. But what if even more clinical trial data were free? The double-blind, placebo-controlled, randomized control trial (RCT) is undoubtedly one of the most elegant inventions of science; designed specifically not just to answer the question of whether a treatment is effective, but to do this with built-in safeguards to protect against human nature. In a well-conducted RCT, it is difficult (though not impossible) to systematically stack the deck by ensuring that the sickest patient or a young parent receives the experimental treatment and not placebo. In the somewhat artificial trial environment, patients, clinicians and researchers all agree to be ‘blinded’ to preserve the integrity of the trial, although inevitably all three groups make guesses; the accuracy of such guesses is even being reported in some studies. However, unblinding becomes more likely when a treatment is strikingly effective, has a known side-effect profile or when the stakes are particularly high. I knew one young patient with amyotrophic lateral sclerosis (ALS) who was dissatisfied with the concept of placebos, so she sent her study medication off to a private laboratory. This laboratory determined whether she was on the treatment “The double-blind, placebo-controlled, randomized control trial (RCT) is undoubtedly one of the most elegant inventions of science; designed specifically not just to answer the question of whether a treatment is effective, but to do this with in-built safeguards to protect against human nature.”