Shares of Japanese metals refiner JX Advanced Metals Corp. slid after the company unveiled a plan to issue ¥250 billion ($1.6 billion) of bonds that can be converted into stocks to fund share buybacks.

The stock fell as much as 15%, the biggest intraday decline since April 2025, after the company said Monday that it is marketing zero-coupon convertible bonds in two tranches of equal size maturing in 2029 and 2031. JX Advanced metals’ largest shareholder Eneos Holdings Inc., which currently holds about 42%, will tender a portion of its take as part of the transaction.