Not without removing a rail. Ridgeback Rails are clearly labeled on the back-side, with the company name. Aside from that, the profile of the back-side of the rail block is unique. Again, this can only be seen with a rail removed.
Ridgeback rails are only made for 7' Valley tables. Brad is correct that you will need to remove a rail in order to check for their logo on the back of the rail.
Removing a rail (It's simple):
1. Remove one of the thin metal strips along the edge of the table. Each strip is held down by a series of screws. One screw about every 18". The strips along the short rail sides will have less screws since their shorter.
2. Next you will see that the rails are held together by 3 bolts which can be unfastened with a socket wrench and extension.
Ridgeback Rails are available for Valley and Dynamo tables of the following sizes: 6.5', 7', and 8'. Rails for other table manufacturers may be available upon special request.