The moment at which labor law establishes the beginning of the period for seeking judicial protection contains an evaluative element ("should have known about the violation of one's rights"). This article attempts to compare the perceptions formed in the legal community with the opinions of individuals working under an employment contract and without legal training regarding the moment when an employee should have known about a violation of their rights (in a claim for recognition of the relationship as an employment relationship). The research draws on court decisions and the results of a survey.