No reference release (upgrade) since 7.1—that is, 7.1, 7.5, 7.6, 8.0, 8.5, 9.0—has ever been either free or downloadable. Even full install CDs of Reference Release and upgrades—such as 7.1.1, 7.5.3, 7.5.5, 7.6, 7.6.1, 8.1, 8.5.1, 8.6, 9.0.4, 9.1—have had to be purchased. Despite that, Apple does now allow downloads of 7.5.3, thereby effectively making that updater into a full installer that does not need a prior installation of 7.5.
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