I thought this issue was settled, but apparently not. From the Korea Herald:
The Korea-U.S. free trade pact has resurfaced as a hot-button issue ahead of the April 11 general elections as the liberal opposition parties vow to scrap it should disputed clauses not be renegotiated.
The liberal forces, led by the main opposition Democratic United Party, argue that without revisions, the pact could encroach upon Korea’s economic sovereignty, while stressing that the ruling bloc railroaded its ratification through parliament last November.
The opposition parties on Wednesday sent a letter to the U.S. government in Seoul, in which they threatened to repeal the pact should the U.S. reject their demand for renegotiations.
“We regard the pact ― rammed through parliament ― as null and void, and call on (the government) to suspend its effectuation,” DUP chairwoman Han Myeong-sook said during a press conference.
The DUP now demands that 10 clauses be renegotiated.
The major bone of contention is the Investor-State Disputes settlement mechanism. The ISD system allows U.S. investors to seek settlements on disputes with Korea in the courts of a third country. The opposition argues this would work mostly in favor of the U.S. with its influence over the international judicial system.