Nexstar to Replace Local Network News Segments With NewsNation

Nexstar Media Group Inc., the largest owner of local television stations in the US, has embarked on a sweeping effort to limit the reach of national networks like ABC, NBC and CBS through its affiliate stations across the country, according to a regulatory document and people with knowledge of the matter.

The Irving, Texas-based media company has begun preventing its stations from filling local newscasts with segments produced by national networks, asking them to use content from its NewsNation cable channel instead.

Nexstar ended its stations’ agreement with Comcast Corp.’s NBC to share nationally reported segments, according ...