Nepenthes ovata was formally described in 1994 by Joachim Nerz and Andreas Wistuba. The holotype, Nerz 1601, was collected on March 16, 1989, on the west ridge of Mount Pangulubao at an altitude of 1800 m. It consists of a rosette with pitchers. Two other specimens were collected at the same time and location. Nerz 1602 includes a vine with pitchers and male flowers, while Nerz 1603 consists of a vine with male flowers. All three specimens are deposited at the National Herbarium of the Netherlands in Leiden.