It's hard to tell what messages persuaded the MEPs to sign. Most are under their party whip, so don't have much say. UK MEPs appear to have signed in alignment with their respective political parties. So the Liberals signed, and engaged in debate, while the Tories ignored all correspondence and didn't sign. Ironic that it is these two parties that are currently sharing power in the UK, yet they have polarise stances on something fundamental to future trade, innovation, and growth.

More interesting are the smaller parties and independents. That's where things look very slimy. For example, UKIP, whom you would expect to favour complete UK autonomy, failed to sign and also would not debate.