A viewer will sometimes find the same series on two or three different services, and assume one of them has it wrongly. All of them usually have it legitimately, because the rights were never sold as one thing.
Rights are divided before they are sold
A programme is not licensed as a single object. It is split by territory, by language, by time window, by exclusivity and by distribution method, and each slice is negotiated separately.
A service can therefore hold exclusive rights in one country while a rival holds non-exclusive rights in another, and neither is in breach of anything.
This division is the point rather than an accident. Selling slices repeatedly earns a rights holder far more than selling the whole once.
Windows stack in sequence and overlap at the edges
Distribution has historically moved through stages, each with its own pricing and audience. Streaming did not remove the stages; it added more of them.
A title may sit in a subscription window on one service, a transactional rental window on a storefront, and an advertising-supported window on a free service at the same time.
The overlaps happen because windows are defined by contract dates that were negotiated at different times, not by a single coordinated schedule.
Exclusivity is narrower than the marketing implies
An exclusive is defined by the specific rights it covers. A service can advertise exclusivity truthfully while the same title runs elsewhere under a different category of rights.
Common carve-outs include airline and hotel distribution, educational licensing, and free advertising-supported channels, none of which compete meaningfully for the same viewing.
The word is doing marketing work rather than describing a legal state, and the underlying arrangement is usually far more complicated than the badge suggests.
Ownership does not settle the question either
A studio that owns a show still licenses it out, because licensing revenue is immediate and certain while subscriber value from exclusivity is neither.
Services that produce their own content face the same calculation, and several have shifted from withholding their catalogues to licensing them again where the numbers favour it.
What appears to viewers as inconsistent strategy is usually a series of individual title-level decisions, each made against its own expected return.
Why titles vanish without warning
A licence has an end date, and the service loses the right to stream on that date whether or not anyone is midway through the series.
Renewal is decided close to expiry and depends on viewing figures the service holds privately, so removals appear abrupt from outside while being routine internally.
The same mechanism explains sudden reappearances, which are new licences rather than restorations, and often carry different territories or a different set of seasons.