Ah great thanks, makes sense. Had a quick look at the act which came out in 1951 and changed many times. This modification refers to a change on the link below.
I am guessing the name would refer to the Casino as per the definition below. Would be good to confirm provenance....just need a Fremont machine to put it in
A registrant in possession of gambling devices manufactured prior to the effective date of this statute should affix a serial number thereto if one is not already so affixed, together with registrant's name and trade name, and a statement indicating that the device was manufactured prior to December 17, 1962.
The act mainly seems to refer to the movement of machines through states where gaming devices are illegal. Thanks for your help
https://www.justice.gov/criminal-oeo/file/623901/download