Apple turned the tables on Qualcomm in a new countersuit, claiming the chipmaker’s popular Snapdragon 800 and 820 products infringe on several of the iPhone giant’s battery life patents.

In a court filing, Apple accused Qualcomm of infringing on at least eight of its patents related to extended battery life, Reuters reported. The patents cover deactivating parts of the processor when not in use and providing more efficient sleep and wake functions. Apple claimed to have sought patents for those features “years before” Qualcomm.

Apple is seeking unspecified damages from Qualcomm.

The countersuit comes in response to an earlier Qualcomm allegation Apple infringed on its battery life patents. Apple initially responded by arguing Qualcomm’s patents were invalid, but changed tack with the legal action.

Apple’s infringement claim against Qualcomm adds to a sprawling legal battle between the two. The spat began in January, when Apple filed a $1 billion lawsuit against Qualcomm accusing it of overcharging for patents and royalties.

Qualcomm denied Apple’s allegations and responded with its own lawsuits arguing Apple abused its market dominance and seeking to compel Apple’s contract manufacturers to make royalty payments as scheduled.

Amid the dispute, Qualcomm’s licensing revenues have dropped, and the company could be facing another blow as reports indicate Apple may turn to Intel and possibly MediaTek rather than Qualcomm in developing future iPhones and iPads.