The fact that it has not been leaked is not proof of the negative. The US had been spying on Europe for 50+ years before Snowden and the US continues to spy on

The fact that it has not been leaked is not proof of the negative. The US had been spying on Europe for 50+ years before Snowden and the US continues to spy on Europe right now without any further leaks -- by your logic that must mean that the US isn't currently spying on the EU, right, or there would be leaks? There's plenty of evidence of the EU spying on allies. I can't tell if your implication is "Europe can't maintain smart enough computer scientists and engineers capable of spying on the US" or "Europe has the moral high ground and doesn't spy on allies". Both are naive.