The named insured is the policyholder, the subcontractor's legal entity listed on the policy and the COI. They have full rights and duties under the policy, including the ability to make claims and request endorsements.
GCs should confirm the named insured on a certificate matches the exact legal entity on the subcontract and W-9. A certificate issued to a different entity, an owner's personal name instead of the LLC, may not cover the work you contracted for.