DISCRETE DIVIDENDS IN EQUITY DERIVATIVES. One of the complications in equity derivative modelling is how to treat dividends. One of the complications in equity derivative modelling is how to treat dividends. On dividend payout, or ex div, dates, the underlying spot drops by the dividend amount, ignoring tax. This introduces discrete deterministic jumps into the geometric Brownian process assumed within the Black-Scholes framework. The underlying stochastic process in the presence of discrete dividend can be expressed as: