Other European Frequent Flyer Programs - Do I need to submit a copy of my passport with a claim?

I have used Euclaim to file for us against Iberia Airlines and the claim has been accepted. Now they are asking me to send in a copy of my passport.

Did they also ask you to do this? Would you have any second thoughts about doing this? As far as identity protection is concerned?

Thanks
Jeff Schaffer
jschaff112@gmail.com