Kuat Drive Yards is one of the four Corporations in the mod and allows a cost and build-time reduction to specific ships and Vehicles only on the planet that the Corporation is built at. This Corporation can be built on the planet Kuat and is available only to the Imperial Remnant.
These are the space units that are affected by the Kuat Drive Yards Corporation:
Sovereign-class Dreadnought, Executor-class Star Dreadnought, Praetor Mark II-class Battlecruiser, Imperial I-class Star Destroyer, Imperial II-class Star Destroyer, Interdictor-class Star Destroyer, Acclamator II-class Assault Ship, Escort Carrier.
These are the ground units that are affected by the Kuat Drive Yards Corporation:
the Imperial Remnant has the ability to construct Imperial Prisons, which gives a build-time reduction. Whilst the Imperial Prison will speed up the time it takes to build the Corporation (even though without it, it still builds pretty quickly), it won't affect the ships and vehicles already affected by the Kuat Drive Yards.
But it is still recommended to build an Imperial Prison with KDY, as the Tector-class Star Destroyer is strangely not affected by KDYs price/build-time reduction bonus.
If Corporations could be made by the other Factions, it should be noted that the Enforcer-class Picket Cruiser may also be affected by the price/build-time reduction bonus because of KDYs involvement of the production of the ship.