Hey guys. I think some of guys already know it but I will just post it. I just checked Bride Japan home page and found they posted how to check fake bride seat (gias,vios3,digo,cuga)
1) go to
www.bride-jp.com
2) check top page left side "news" then click "copy商品にご注意ください"（click copy product). There are some PDF files with pics. You can see pics of fake and authentic bride seat. They explain detail of difference.
Also, they said if you are not sure your seat is fake or not, they can investegate for you (You need to contact them and send your seat pics)!
I hope it will help you guys!
Thanks.