src: www.latimes.com
Major League Baseball games not broadcast exclusively by its media partners are televised by regional sports networks, which present sports programming of interest to their respective region. Most MLB broadcasters are members of chains such as NBC Sports Regional Networks, Fox Sports Networks, and AT&T SportsNet, although several teams are broadcast by regional networks that are independent of these chains. Some teams own partial or majority stakes in their regional broadcaster.
Regionally broadcast MLB games are subject to blackouts; games from outside of a viewer's designated market are blacked out to protect the local team.
Source of article : Wikipedia