The definition of contractor in the FAR is offered more than once, and generally in specific context to the policy area covered in that part of the FAR.
One could interpret these examples to imply a generally inclusive definition of what is a contractor, unless specific exceptions can be cited from statute, case law, and the like. It may not be suitable to state in regulation a single harmonious, universal definition of contractor since there can be many different contexts in which its rules may apply, or exceptions thereof.
FAR 9.403
?Contractor? means any individual or other legal entity that?
(1) Directly or indirectly (e.g., through an affiliate),
submits offers for or is awarded, or reasonably may be
expected to submit offers for or be awarded, a Government
contract, including a contract for carriage under Government
or commercial bills of lading, or a subcontract under a Government
contract; or
(2) Conducts business, or reasonably may be expected
to conduct business, with the Government as an agent or representative
of another contractor.
FAR 3.502-1
?Prime Contractor? means a person who has entered into a prime contract with the United States.
FAR 22.801
?Prime contractor? means any person who holds, or has held, a Government contract subject to E.O. 11246.
FAR 44.101
?Contractor? means the total contractor organization or a separate entity of it, such as an affiliate, division, or plant, that performs its own purchasing.
I do not have a reply to your GE example, but there could be many context-specific, regulatory and policy considerations for reaching the proper conclusion whether that corporate unit is a contractor. As you've stated, it's not clear until you examined which ones may apply to your situation(s).
HTH
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