So did I
My Previous marriage was to a British Citizern, we divorced.
I rang my private pension company 2 years ago to get some info and was told that my 'ex' had 'interests' on my pension.
Off the record the man said that my ex wife 'could' claim 505 of my pension as i took it out while I was married to her at the time...so you can see my worries here (I hope )