What is the subjective of this sentence? [closed]

Dong,2019 said that

A firm that colludes with other firms in a foreign product market is subject to that country’s antitrustlaws. Foreign leniency law passage is thus likely to affect firms that operate across borders, not least because antitrust authorities coordinate their actions in prosecuting similar cartels

So "that" in the phrase "that country’s antitrustlaws" in the first sentence represents "A firm" or "other firms". I thought it represents "a firm" but it is meaningless if it is the case because it is for sure a firm will be affected by its country's antitrustlaws.

I doubted that"that country's antitrustlaws" are antitrustlaws of "other firms" in this circumstance.

Update: Can this first quoted sentence be simply translated to "If firm A in the US colludes with firm B in China, firm A is also subject to China antitrust laws".

Solution 1:

A firm that [relative pronoun with the referent NP “a firm”] colludes with other firms in a foreign product market is subject to that [demonstrative adjective/determiner] country’s antitrustlaws.

Foreign (adjective) = a foreign country’s

As a demonstrative adjective/determiner “that” refers to an object that is more distant in space or time. Often, and in this case, it is the noun in the subordinate clause, thus “that country’s” refers to “a foreign country’s”