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Existence and uniqueness for backward stochastic differential equations driven by a random measure

We study the following backward stochastic differential equation on finite time horizon driven by an integer-valued random measure $μ$ on $\mathbb R_+\times E$, where $E$ is a Lusin space, with compensator $ν(dt,dx)=dA_t\,ϕ_t(dx)$: \[ Y_t = ξ+ \int_{(t,T]} f(s,Y_{s-},Z_s(\cdot))\, d A_s - \int_{(t,T]} \int_E Z_s(x) \, (μ-ν)(ds,dx),\qquad 0\leq t\leq T. \] The generator $f$ satisfies, as usual, a uniform Lipschitz condition with respect to its last two arguments. In the literature, the existence and uniqueness for the above equation in the present general setting has only been established when $A$ is continuous or deterministic. The general case, i.e. $A$ is a right-continuous nondecreasing predictable process, is addressed in this paper. These results are relevant, for example, in the study of control problems related to Piecewise Deterministic Markov Processes (PDMPs). Indeed, when $μ$ is the jump measure of a PDMP, then $A$ is predictable (but not deterministic) and discontinuous, with jumps of size equal to 1.