How do I know when I-140 is filed ? no signature is requested to sign on any paper

I submitted all required documents to attorney for processing I-140.
It’s being one week and more after PERM gets approved, I don’t receive any notification or confirmation from attorney/HR saying I-140 is being filed.
Does anyone has experience that I-140 is filed and employee doesn’t get aware of (no signature is asked to sign)?

I140 is an employer application and hence no employee signatures are required as far as I know.


I heard the employee need to sign on the perm certification, is that true?