There is no evidence that EU citizens have signed the petition at a rate different from U.K. citizens. Unless you have some evidence?
Well, I suppose I could look up the demographics for places like Cambridge and Bristol - I guess if they have higher concentrations of EU nationals living there - that might prove a point.
From Channel 4:
It’s also worth noting that people who are resident in the UK but not citizens can legitimately sign the petition, whereas the voting rules in the 2016 EU referendum were very different.
Most EU citizens living in Britain could not vote for or against Brexit, so it’s possible that a significant number of people signing the petition did not take part in the referendum.
You can sign using a false name
We tested the system in the newsroom, and we found that it’s very quick and easy to sign the petition using a false identity.
We created an account under a made-up name with an email platform that doesn’t have strict rules about verifying the identification of its users.
The petition sent an email to the bogus email account and we could have registered our signature if we had clicked on the link.
This opens the question of whether individuals have signed the petition multiple times using pseudonymous accounts, perhaps using different devices with different IP addresses.