Unionized members of Kakao stage a demonstration near the company's headquarters in Pangyo, Gyeonggi Province, May 20. Yonhap A labor union at Kakao, the operator of Korea's popular messenger service, and the company's management will undergo a second round of mediation with the Gyeonggi Regional Labor Relations Commission later Wednesday, industry sources said.The mediation procedures, set to take place at 3:00 p.m., come after the two sides failed to narrow differences in the first round of wage talks held May 18, according to sources.If the regional labor office decides to suspend the mediation, unionized members at Kakao's headquarters will secure their rights to strike, along with unions at four of the company's affiliates.The five labor unions had voted last week in favor of a walkout after wage negotiations with management fell through.The latest development comes amid broader calls for performance-based bonuses and profit sharing in Korean companies, sparked by the recent labor-management dispute at Samsung Electronics.Kakao's union is reportedly seeking to include restricted stock unit grants, a form of equity compensation from the company, in the official performance-based incentive pool.