If you take a look at an enlarged view of the back of the disc, you can see that the acceptance marking is not just a broad arrow, it is actually a one strike stamp of a broad arrow with an 'I' or similar below it.
Printable View
If you take a look at an enlarged view of the back of the disc, you can see that the acceptance marking is not just a broad arrow, it is actually a one strike stamp of a broad arrow with an 'I' or similar below it.