본 연구는 노동조합이 기업의 채권신용등급에 미치는 영향을 분석하였다. 본 연구에서 사용한 채권신용등급은 한국신용평가, 한국신용정보, 그리고 한국기업평가 3사가 동일한 신규발행채권에 대해 부여한 각 채권신용등급의 평균값이며 실증분석 결과는 다음과 같이 요약된다. 첫째, 노동조합이 존재하는 기업이 그렇지 않은 기업에 비해 채권신용등급이 낮았다. 둘째, 노동조합의 협상력이 강할수록 채권신용등급이 낮았다. 이러한 결과는 선행연구 및 언론을 통해 보고된 바와 같이 노동조합의 존재가 실질적으로 기업의 경영환경에 상당한 영향을 미치고 있으며 이러한 특성들로 인해 기업의 신용위험이 달라진 것으로 해석될 수 있다. 다음으로 노사관계를 신용평가에 반영함에 있어 신용평가기관 3사가 차이를 보이는지를 분석하기 위하여 신용평가기관 3사가 동일한 신규발행채권에 대해 부여한 각각의 채권신용등급을 사용하여 분석을 수행하였다. 분석결과 3사 모두 노동조합이 존재하면 낮은 채권신용등급을 부여하는 것으로 나타났으나, 노동조합의 협상력 크기에 대해서는 일관된 결과를 보이지 않았다. 요약하면 신용평가기관 3사가 모두 신용평가에 노사관계를 고려하고 있으나 동일한 정도로 반영하고 있지 않은 것으로 해석할 수 있다. 추가분석 결과, 노동조합 관련 변수와 채권신용등급 간의 상관관계는 회계정보의 질과 지배구조를 통제한 후에도 유의하였다. 이는 노동조합 관련 변수가 신용평가의 근간을 이루는 재무정보 및 지배구조에 추가적으로 채권신용등급 결정에 영향을 미치고 있음을 의미하는 것으로, 선행연구 및 신용평가기관이 밝히고 있는 평가 기준과도 일관된다. 본 연구를 통해 노사관계가 타인자본비용에 미치는 영향에 대한 이해를 증진시켜 학계와 실무계에 시사점을 제공할 수 있을 것으로 기대한다. 또한 신용평가기관의 평가실무에 대한 이해를 보다 풍부하게 할 수 있을 것이다.
This study examines the impact of labor union's activity on the credit rating. Credit rating shows redemption possibility of principal and interest until maturity. So, future cash flow forecast is important for credit rating. The influence factors of future cash flow is various. But, because the best information source of firm's financial position and performance is financial statement, prior studies investigate the relation between the quality of financial reporting or disclosure quality and credit rating. Prior studies commonly reported that credit rating is positively related to the quality of financial reporting or disclosure quality because these firms figure out useful information about future cash flow. According to the rating agencies' evaluation method, rating agencies consider various influence factors of future cash flow and consider both financial statement information and non-financial information like industry analysis, operation analysis, and management analysis in evaluating firms' credit rating. This study extends the existing literature by investigating the impact of the activities of labor union which is one of major stakeholder on firm's credit rating. Also this study extends the existing literature focused on financial information by investigating the impact of non-financial information. According to the negative impact of labor union on return on asset, asset volatilities, default threshold and cash flow which is main factors of Merton model, Chen et al.(2011) reported positive relation between labor union's bargaining power and bond yield spread. However, Chen et al.(2012) reported that labor union's bargaining power is negatively related with bond yield spread. Unlike prior studies focused on bond yield spread, this study focuses on credit rating. We investigate rating agencies consider labor-management relations to credit rating. Our study is one of the first to investigate the relation between labor union and cost of debt capital in Korea. Specifically, we expect that labor union which is determinants of firm's performance and management decision making influences credit risk. From a negative perspective, if labor union exists, cash flow uncertainty increases because of demand for higher wages, strike. And to negotiate from a position of strength, labor union deteriorates financial reporting quality, increase information asymmetry, and financial leverage. Then credit risk is increased. From a positive perspective, labor union improves firm's performance, financial reporting quality, disclosure quality, and prevents risky investment decision making by integrative negotiation. Then credit risk is reduced. So our first hypothesis is that credit rating differs between with labor union and without labor union. Second hypothesis is whether bargaining power of labor union impacts credit rating. Our study's credit rating is the average of bond ratings received by three credit rating agencies(Korea Investors Service, NICE, and Korea Ratings 3rating agencies). And empirical results support our hypotheses. First, the credit rating is significantly poor for firms with labor union. Second, unions' bargaining power is negatively related with firms' credit rating. Next, we examine whether each credit agency evaluates the impact of labor union differently, using individual credit rating data of three credit agencies for a given bond of a firm. Our results show that all three credit agencies assign a lower rating for firms with a labor union. However, we do not find consistent results for the relation between credit rating and labor unions' bargaining power. In summary, all three rating agencies considers labor-management relations in credit rating. But each credit agency evaluates the impact of labor union differently. The results remain robust after we control for accounting information quality and governance structure. The results provide an evidence that the presence of labor union and its bargaining power substantially affect firm's business circumstances and therefore labor-management relations are related with firms' credit risk.