Enemies of a house

[Kosa]

This all started here. Citing a line from a special forces ID:

"Marinenachrichtendienst ID:

...
-Can attack ships which belong to a house or organisation considered hostile by Rheinland outside their Zone of Influence. Can demand transports which belong to a house or organisation considered hostile by Rheinland to drop all cargo and attack if they refuse to comply.
... "

But I don't find a clear description which are the enemies of Rheinland or Liberty. I know the usual pirate factions are hostile. But what about the corporations of a house they are at war with? Are they hostile too? Same goes for other houses.
I'm expecting grounded answers. No speculations please.

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