The fusion orbit category of a discrete group over a collection is the category whose objects are the subgroups in , and whose morphisms are given by the -maps modulo the action of the centralizer group . We show that the higher limits over $\overline{\mathcal F _{\mathcal C}} (G)$ can be computed using the hypercohomology spectral sequences coming from the Dwyer -spaces for centralizer and normalizer decompositions for . If is the discrete group realizing a saturated fusion system $\mathcal F$, then these hypercohomology spectral sequences give two spectral sequences that converge to the cohomology of the centric orbit category ${\mathcal O}^c (\mathcal F)$. This allows us to apply our results to the sharpness problem for the subgroup decomposition of a -local finite group. We prove that the subgroup decomposition for every -local finite group is sharp (over -centric subgroups) if it is sharp for every -local finite group with nontrivial center. We also show that for every -local finite group $(S, \mathcal F, \mathcal L)$, the subgroup decomposition is sharp if and only if the normalizer decomposition is sharp.

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