More than two months after his company announced that it was under investigation by Chinese antitrust authorities, Qualcomm Inc. chief executive officer Paul Jacob said in an interview that he still didn’t know why.

It wasn’t until Feb. 19 that Xu Kunlin, chief of the price supervision and antimonopoly bureau for China’s National Development and Reform Commission, said the investigation was based on complaints filed by trade associations and competitors that had accused Qualcomm of abusing dominant market position to charge higher prices in China. Xu also confirmed that a similar investigation was launched against wireless technology developer InterDigital Inc.