Perm duties different than H1B extension duties

[h1_seeker]

Can perm duties differ from 6th year H1B extension duties within the same field? Is it true that perm duties are for future employment and can be different than H1B duties if they are within the same field?

[Attorney_11]

A PERM Labor Certification may be completely different in job, scope, location, employer and duties than the H1B petition for an individual who will be the beneficiary of the PERM Labor Certification. The Green Card process is, in the eyes of the law, considered a sponsorship for a future job opportunity for a position that is currently open and unable to be filled permanently due to a lack of able, willing and qualified US workers for the position.

[h1_seeker]

Just so I understand correctly, can 6th year H1B extension duties differ from perm duties (both within the same field) even when I file for H1B extension after perm approval? Thanks a lot for your response.