Samsung Electronics on Wednesday announced changes in the leadership of its memory and foundry chip divisions, as the company faces intense competition in the semiconductor space.

The South Korean tech giant appointed Jun Young-hyun as co-CEO and head of the memory chip arm, while Han Jin-man will become the president and head of the company’s foundry business.

The company also appointed Nam Seok Woo, previously head of chip factory engineering and operations, as the chief technology officer of the foundry business in a newly established position.

Samsung shares fell 3%. The company’s stock has been on a steady decline amid investors worries that Samsung was falling behind competitors such as SK Hynix in building advanced chips.

Samsung Electronics was once the leading force in the memory chip sector, and appeared well-positioned to take advantage of the boom in artificial intelligence. However, the company has been left behind by SK Hynix in developing next-generation chips, which have become integral components for AI silicon leader Nvidia.

Last month, Jun, who has been overseeing the semiconductor division since May, issued a rare apology after the company posted disappointing third-quarter profit guidance. Samsung’s chip business posted a sharply lower third-quarter profit compared to the previous quarter.

“Samsung appears to be pursuing an operational change while maintaining stability as it has made no significant change in top management, in our view,” Citi analysts wrote in a note following the reshuffle.

“Samsung aims to strengthen its memory business division under the direct control of the head of the Device Solutions (DS) division, appointing the head of DS division as a CEO,” Citi analysts said, adding the the firm could “overcome business uncertainty” through Jun’s leadership.