Apologies if this has been asked before but I can't seem to find an official rule for the contain defence token in either the rules of the FAQs, could somebody please point me in the right direction to find it?

Thank you in advance.

http://starwars-armada.wikia.com/wiki/Contain

A ship can spend this defense token to prevent the attacker from resolving the standard critical effect. The attacker can still resolve a non-standard critical effect, such as one granted by an upgrade card

You'll find this printed out on the sheet that comes with the ISD and MC80.

Yeah, it's a little bit at the top of one side of the single piece of paper that comes with either of the 2 large ships. The sheet with the expansion contents list.

I very nearly threw mine out because I didn't see the rules text on it when I opened my ISD.

Thanks for your replies, I think I must have thrown mine out. Doh.