The CFC tax regime affects taxpayers that are shareholders of foreign entities located (i.e. seated or having a place of management or being registered or situated) in: 
(I) countries recognised as applying harmful tax competition i.e., in the so-called tax havens  
or
(II) countries with which Poland/EU have not ratified any treaty (e.g. DTTs) allowing for exchange of tax information 
No other conditions have to be met in these cases for the foreign entity to be considered as a CFC.
In addition, a controlled foreign company (III) will be an entity that meets all of the following conditions:
the control level condition - Polish tax residents have directly/indirectly, solely or jointly with related entities or with non-related entities being Polish tax residents, over 50% participation in the foreign company s income, voting rights, or capital or exercise actual control over the foreign entity.
the level of taxation condition - Income tax actually paid by the foreign entity (not subject to refund or credit in any form, including the refund or credit for the benefit of another entity) is lower by at least 25% than the income tax that would be paid by this foreign company in Poland at the application of the 19% tax rate (if it was a Polish tax resident)
the revenue structure condition   at least 33% of the revenue of this entity earned in the tax year comes from the indicated sources (so-called passive income)
As of 2022. there are also 2 more categories of CFC entities regarding so-called "shell companies 
The first is entities (IV) that, in addition to meeting the level of control and the level of taxation conditions, have assets that generate passive income with a value equivalent to at least 50% of the value of the entity's total assets, and the passive income is less than 30% of the value of assets and receivables.
The last category of CFC (V) entities are those defined by reference to the rate of return on assets held. A foreign entity will be considered a CFC if, in addition to the level of control condition and the level of taxation condition, it earns income in excess of the income calculated according to the formula: (b + c + d)   20%, in which the various letters stand for: b - the carrying value of the entity's assets, c - the entity's annual employment costs, d - the accumulated (summed) previous depreciation and amortization within the meaning of the accounting regulations, and less than 75% of the entity's income is derived from transactions with unrelated parties domiciled, established, managed, registered or located in the same country as the entity.