Spanish stative verb saber (to know) can change its lexical aspect to achievement ('begin to know') or to bounded state ('knowing for some time'), when it's in simple past tense (supo). This suggests that the type of situation does not depend only on the perfective operator. This paper, based on the analysis of 232 cases collected from the currentSpanish language corpus of the Real Academia Española (CREA), shows that lexical, grammatical, and discursive meaning affect the determination of the type of situation of supo. Specific interpretation depends on the properties of the reference time in which the situation is located.