Seoul shares closed lower Friday as investors stayed cautious ahead of key U.S. inflation data expected later this week.

The benchmark Korea Composite Stock Price Index(KOSPI) fell ten-point-31 points, or zero-point-32 percent, Friday to close at three-thousand-186-point-01.

Tech and pharmaceutical stocks led the declines, with Celltrion falling two-point-78 percent, Naver down one-point-38 percent and Kakao dropping one-point-57 percent. 

Shipbuilding shares, however, gained, with HD Hyundai Heavy Industries jumping three-point-38 percent and Hanwha Ocean adding two percent.

The tech-heavy KOSDAQ lost one-point-52 points, or zero-point-19 percent, to close at 796-point-91.