The possible irregularities are centered on Woori Bank, one of the major shareholders of K-Bank with a 10-percent stake, according to the panel.
Under banking laws, Woori Bank was required to have a capital adequacy ratio of more than the average ratio of banks when financial authorities granted preliminary approval for K-Bank.
At that time, Woori Bank's quarterly capital adequacy ratio stood at 14 percent, slightly below the average ratio of 14.08 percent.
Woori Bank asked the Financial Services Commission to apply the bank's average capital adequacy ratio over the past three years, instead of the quarterly ratio.
By accepting Woori Bank's request, the FSC ruled that Woori Bank's capital soundness made it eligible to become a major shareholder of K-Bank, the panel said.
Yoon Seok-heon, head of the panel, said there was a "problem in administrative procedure" in approving Woori Bank's status as a major shareholder of K-Bank.
However, Yoon said the panel found no clear evidence that the FSC violated relevant laws. (Yonhap)