South Korean shares closed sharply higher on Thursday after two consecutive days of losses, with the primary index climbing 6% after investors pinned high hopes on strong shareholder returns from Samsung Electronics (KRX:005930) and SK hynix (KRX:000660).

Investor hopes came after SK Hynix on Wednesday approved a 40 trillion won share repurchase and cancellation plan. The buyback is set to begin Aug. 20 and run for about three months. Samsung Electronics' shareholder return policy is expected to be announced later in August. Shares of SK Hynix and Samsung Electronics added nearly 13% and over 9%, respectively, at market close.

The Korea Composite Stock Price Index, or Kospi, increased by 381.41 points, or 5.9%, to close at 6,852.58. The Kosdaq also rose by 16.43 points, or 2%, to close at 840.89.

In corporate news, Kolon Corporation's (KRX:002020) subsidiary Kolon Global (KRX:003070) secured an order worth 104.8 billion won for the Pyeongtaek P5 water purification plant (Phase 3) from Samsung Electronics, according to a Thursday filing with the Korea Exchange.

The project is being disclosed after an amended contract raised its value above the applicable disclosure threshold. The initial contract was signed on June 9, 2025.

Shares of Kolon Corporation fell over 3% at market close, while those of Kolon Global added 2%.

In other news, Kakao Corp. (KRX:035720) subsidiary and taxi-hailing and mobility platform Kakao Mobility has confidentially filed for an initial public offering in the U.S. in June and seeks to raise about $1 billion, Yonhap News reported Thursday, citing a financial market tracker.

Bank of America, Morgan Stanley, and UBS are listed as underwriters for the IPO, the report said.

Kakao Mobility did not immediately respond to MT Newswires' request for comment.

Shares of Kakao Corp. added over 3% at market close.