[NolF]

The producers likely have distribution agreements on a by-country basis. So, for example WB cannot distribute <movie> in Germany because GEMA has the rights. But GEMA didn't buy the rights for the English subtitles. I imagine technically WB could then sell subtitles rights for <movie> in Germany but it would be a pain because maybe those subtitles were done by <subcompany> for licence in America and Oceania... etc.

[crucialfelix]

GEMA is a collection society for musical performing and mechanical reproduction rights. Equivalent to BMI / ASCAP. They have nothing to do with films.

They certainly do not buy rights for anything at all. They represent copyright holders and collect fees and distribute them.