Is it possible to receive tax deduction for a U.S. company A with more than 10% of its shares owned by a Korean company G, if it establishes a foreign-invested company in Korea?

If a foreign company with direct or indirect investment from a Korean citizen or company (excluding overseas Koreans with permanent residence or equivalent status) conducts foreign investment in Korea, then the investment rate of the Korean citizen or company is not subject to tax deduction pursuant to Art. 121 of the Special Tax Treatment Control Law.
If the rate of investment by the Korean citizen or company is less than 10%, this rule does not apply.
In this case, the rate of investment by the Korean company G is more than 10%, and thus, that part will be applicable to tax deduction.