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During the twentieth century, the probabilistic nature of quantum mechanics was demonstrated through an extensive list of multiplemeasurement schemes. The most wellknown of these are Bell's Inequalities, where entangled but spacially separated systems can yield correlations higher than possible in deterministic models. A second set of measurement schemes, referred to as LeggettGarg Inequalities (LGI), similarly demonstrate this quantum reality through the temporal correlations of a single system. However, expanding LeggettGarg Inequalities to open quantum systems requires that the coherences of the system be maintained. Here we develop an expansion of the LeggettGarg parameter $K_{3}$ to open quantum systems through the framework of $mathcal{PT}$symmetry, which predicts nonunitary but coherent evolution. We show that open systems allow $K_{3} \geq 1.5$, which marks the upper bound possible with unitary evolution. We found that $K_{3}$ approaches the algebraic bound as exceptional points are approached from the $mathcal{PT}$symmetric regime, and that the algebraic bound is always achievable in the $mathcal{PT}$broken regime. Our findings can be recreated through the postselection of systems governed by the Lindblad master equation, allowing verification through existing experimental platforms. Furthermore, our approach provides a framework for the expansion of multiplemeasurement schemes such as other LeggettGarg Inequalities, Bell Inequalities, or the Jarzynski Equality to nonHermitian systems, while keeping the $\mathcal{PT}$symmetric, $\mathcal{PT}$broken, and triviallybroken regimes accessible.* *In collaboration with Sourin Das Group and Kater Murch Lab Jacob is a postdoc in the group of Yogesh Joglekar (who is giving a quantum Lunch talk on Tuesday) Host: Avadh Saxena 