This article is devoted to studying the non-commutative Poisson boundary associated with $Big(Bbig(mathcal{F}(mathcal{H})big), P_{omega}Big)$ where $mathcal{H}$ is a separable Hilbert space (finite or infinite-dimensional), $dim mathcal{H} > 1$, with an orthonormal basis $mathcal{E}$, $Bbig(mathcal{F}(mathcal{H})big)$ is the algebra of bounded linear operators on the full Fock space $mathcal{F}(mathcal{H})$ defined over $mathcal{H}$, $omega = {omega_e : e in mathcal{E} }$ is a sequence of positive real numbers such that $sum_e omega_e = 1$ and $P_{omega}$ is the Markov operator on $Bbig(mathcal{F}(mathcal{H})big)$ defined by begin{align*} P_{omega}(x) = sum_{e in mathcal{E}} omega_e l_e^* x l_e, x in Bbig(mathcal{F}(mathcal{H})big), end{align*} where, for $e in mathcal{E}$, $l_e$ denotes the left creation operator associated with $e$. The non-commutative Poisson boundary associated with $Big(Bbig(mathcal{F}(mathcal{H})big), P_{omega}Big)$ turns out to be an injective factor of type $III$ for any choice of $omega$. Moreover, if $mathcal{H}$ is finite-dimensional, we completely classify the Poisson boundary in terms of its Connes $S$-invarinat and curiously they are type $III _{lambda }$ factors with $lambda$ belonging to a certain small class of algebraic numbers.
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