Having delivered a heavy blow to the semiconductor plans of China’s biggest technology manufacturer, the U.S. government now seems keen to knock down the nation’s biggest contract chipmaker. The action looks opportunistic.

Export restrictions placed on Semiconductor Manufacturing International Corp. mean U.S. companies will have to apply for a license to sell some products to the Shanghai-based chipmaker.

The rules don’t appear as strict as those placed on Huawei Technologies Co. earlier this year, according to Bloomberg News. That move ended up forcing suppliers like Taiwan Semiconductor Manufacturing Co. to stop making chips to the Chinese company’s design.