RT Journal Article SR Electronic T1 Pricing Vulnerable Black-Scholes Options with Dynamic Default Barriers JF The Journal of Derivatives FD Institutional Investor Journals SP 62 OP 69 DO 10.3905/jod.2003.319206 VO 10 IS 4 A1 Cho Hoi. Hui A1 Chi-Fai. Lo A1 H.C. Lee YR 2003 UL https://pm-research.com/content/10/4/62.abstract AB The “structural approach” to modeling credit risk specifies a stochastic process that the net asset value of the issuing firm is assumed to follow. If firm value falls below a certain “default barrier,” bankruptcy is triggered and the firm is assumed to default on its vulnerable obligations. In this article, Hui, Lo, and Lee apply the methodology to price vulnerable options written by a default risky firm. They show how a variety of default scenarios may be accommodated by use of a dynamic default barrier, while maintaining a closed-form valuation equation.