Qualcomm is losing a key executive while in the midst of serious legal battles with one of its largest customers, Apple.

The company announced Thursday that after 17 years in his role as Qualcomm president, Derek Aberle will be stepping down from his position effective Dec. 31, 2017.

Qualcomm did not indicate a reason for the change, but CEO Steve Mollenkopf said: “On behalf of the executive team, I want to thank Derek for the vision, creativity, dedication, and judgment he brought to the company and wish him all the best in the future.”

For his part, Aberle commented, “Over the past 30 years Qualcomm has invented the core technologies that have enabled the mobile revolution and made all modern smartphones possible, I am very proud to have been a part of that tradition of innovation, and of all that we’ve been able to accomplish during my tenure.”

Qualcomm also announced EVP and QTL President Alex Rogers will report directly to Mollenkopf as part of the transition.

The departure comes at a time when Qualcomm is dealing with legal disputes with Apple. Earlier in August, the U.S. International Trade Commission (ITC) voted to launch an investigation into Qualcomm’s patent infringement claims against the iPhone vendor. 

ITC said within 45 days of commencing the investigation it will set a target date for completion. It could take between 16 and 18 months for the investigation to be completed.

The dispute started back in January when Apple sued Qualcomm for $1 billion, alleging the supplier abused market powers and demanded unfair royalties. Qualcomm called the claims “baseless” and an intentional mischaracterization of its agreements with the smartphone maker.

Then in May, Qualcomm filed a suit against four Apple manufacturers requesting owed royalties and alleging that the companies were following instructions from Apple not to make payments to the chip maker.