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### Abstract

We prove that the law of a random walk ${X}_{n}$ is determined by the one-dimensional distributions of $max({X}_{n},0)$ for $n=1,2,...\phantom{\rule{0.166667em}{0ex}}$, as conjectured recently by Loïc Chaumont and Ron Doney. Equivalently, the law of ${X}_{n}$ is determined by its upward space-time Wiener–Hopf factor. Our methods are complex-analytic.

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