Country of Origin Requirements & Service Contracts

Does anyone know if there are any country-of-origin requirements that apply to contracts for services, other than construction?

FAR 25.402(a)(2) states that "[t]he contracting officer shall determine the origin of services by the country in which the firm is established." But, what is the significance of such a determination? The only contract clauses that impose a country of origin requirement are for supply and construction contracts (e.g., 52.225-1, -5, -9, -11). I'm not aware of any clause that addresses the origin of services. So, if the contracting officer determines that the firm is established in another country, what is the impact? Of, if the CO determines that the firm is established in the US (for, example, is incoporated and has an office here), is there any constraint in having the services actually performed in another country?

For example, if there's a solicitation for some sort of help desk requirement and nothing in the SOW says where the help desk needs to be located, is there any standard FAR provision that limits the country from which that service can be provided?

I know there may be some other contractual requirments that indirectly affect this. Export control requirements on sending information to a foreign national or security clearance requirements, for example, may have the effect of preventing someone from having a service performed in another country.

Any thoughts?