If it does not have a serial number, no one on this board can own one because that is in violation of federal law. Since a machinegun has to be registered with the government, it's really hard to do that if it doesn't have a serial number.
I own a Cobray M11/9 submachinegun and it DOES have a serial number.
Uhh, yeah, I don't think ATF would approve a Form 1 or Form 4 without a serial #.
All my title II firearms have serial numbers. I had to tell ATF what the serial numbers would be on each Form 1.