Airlines established in Poland must be majority owned and effectively controlled by EU states and/or nationals of EU states, unless otherwise provided for through an international agreement to which the EU is a signatory.
"Article 4 - Conditions for granting an operating licence:
An undertaking shall be granted an operating licence by the competent licensing authority of a Member State provided that: [...]
(f) Member States and/or nationals of Member States own more than 50 % of the undertaking and effectively control it, whether directly or indirectly through one or more intermediate undertakings, except as provided for in an agreement with a third country to which the Community is a party; [...]" (Regulation (EC) No 1008/2008 on common rules for the operation of air services in the Community, Article 4(f))

Regulation (EC) No 1008/2008 on common rules for the operation of air services in the Community, Article 4(f)
Aviation Act (Dz.U. 2002 nr 130 item 1112), last amended by the Act of 17 March 2021
[<a href="https://eur-lex.europa.eu/legal-content/EN/TXT/?uri=CELEX%3A02008R1008-20201218">Regulation</a>],[<a href="http://isap.sejm.gov.pl/isap.nsf/DocDetails.xsp?id=WDU20021301112">t</a>]