Looks to me like the author mischaracterized the mags as counterfeit when it's actually a licensing issue. They appear to be using the name Glock to describe what the mags are for, not claiming they are actually Glock manufacturer products. Glock is way into protecting its brand. A couple of years ago, I was shopping for a cheap Airsoft Glock to use for a teaching tool. Several companies had posted the "cease and desist" threat letters from the Glock legal team. No unlicensed use of their names or copies of their designs.