What's the difference between H1B LC and GC LC ??

LC in an H-1B context is called Labor Condition Application (actually LCA). Its primary use is to prove (or at least state) that the beneficiary is going to be paid the prevailing wage.

LC in a GC context is Labor Certification and its use is to prove (or ensure.. though it rarely does) that the beneficiary is not replacing an American citizen. This is certified by the state and the federal labor departments.
 
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