What is the ruling concerning fruit that is eaten by people or birds before the estimation or if nothing is left by the estimator?

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Passersby and birds consume the fallen fruit. If the estimator leaves nothing, the owners still have the right to eat fruit equivalent to the amount that was not left for them, and this amount is not counted against them. This is affirmed because it constitutes their established right. The ruling concerning grapes is the same as the ruling concerning dates from palm trees.