A basketball game can be carried by a national broadcaster and by two local ones simultaneously. That overlap is designed, and the rules deciding which feed a viewer receives are contractual.
Two separate rights markets exist
The league sells a national package covering a subset of games shown across the country, while each team separately sells rights to its remaining games within its home territory.
National income is shared equally among teams, which supports competitive balance. Local income is retained by the team that earned it, which does the opposite.
The gap between large-market and small-market local deals is therefore one of the main sources of financial inequality within the competition.
Territories are defined maps, not cities
Each team holds an exclusive home territory drawn as a set of geographic areas, and its local broadcaster may distribute within that boundary only.
These maps were drawn when cable distribution defined markets, and they persist because renegotiating them would redistribute value between owners.
Streaming exposes their arbitrariness, since a subscriber's location is determined by address or network rather than by anything resembling a viewing habit.
Exclusivity windows resolve the conflict
When a game appears in the national package, the local broadcasters are typically blacked out for that game, so the national feed is the only one available anywhere.
The rule protects the value of the national deal, which was sold on the promise of a nationwide exclusive audience for the games it contains.
Selection of which games enter the national package happens well before the season, with a limited ability to change fixtures later as form develops.
Out-of-market packages sell what local rights exclude
Viewers outside a team's territory cannot receive its local broadcast, so the league sells a separate product carrying those games nationally to subscribers.
That product exists only because of the territorial structure, and its content is defined negatively as everything the local and national deals do not already cover in a given place.
Its economics depend on fans living away from their team, a population that has grown steadily and made the package more valuable than the structure originally anticipated.
The structure is under pressure from distribution
Local rights were built on cable subscription income, and the decline of that model has weakened the regional broadcasters who pay for them.
Leagues have responded by taking on distribution themselves in some markets, which converts a rights sale into an operating business with different risks.
Any wholesale change would redistribute income between teams, so the transition is slow and negotiated piece by piece rather than announced as a redesign.
