Abstract： 

A new asymptotic expansion scheme for backward SDEs (BSDEs) is proposed. The
perturbation parameter “ε” is introduced just to scale the forward stochastic variables
within a BSDE. In contrast to the standard smalldiffusion asymptotic expansion method,
the dynamics of variables given by the forward SDEs is treated exactly. Although it
requires a special form of the quadratic covariation terms, it allows rather generic drift as
well as jump components to exist. The resultant approximation is given by a polynomial
function in terms of the unperturbed forward variables whose coefficients are uniquely
specified by the solution of the recursive system of linear ODEs. Applications to a jumpextended Heston and λSABR models for European contingent claims, as well as the utilityoptimization problem in the presence of a terminal liability are discussed. 