Hi, welcome to Just Answer. I will help you with your question.
Practice Direction 4A.2 to the Civil Procedure Rules (available here: http://www.justice.gov.uk/courts/procedure-rules/civil/rules/pd_part05a#IDASOV1) makes it clear that non-parties to proceedings may obtain copies of the Claim Form, but NOT documents attached to it, without the permission of a Judge. So, anybody can get the actual claim form, but not any particulars of claim attached to it or supporting documents etc. without the Court's permission.
I hope this answers your question. If you need further information, just let me know. Please remember to rate my answer as highly as you can.
In what situations would the court give permission to obtain the supporting documents?