King usurping title of their vassal Duke working as intended?

[TehJumpingJawa]

As the Queen of Wales/England/Scotland I have a claim (Strong) on a Duchy held by one of my vassals.

Here's the de jure borders of the Duchy:

and the de facto borders:

If I go ahead and usurp the Duchy (the intent being to neaten up the borders, and weaken the vassal), here's what happens:

All of her vassal counts go independent! Both de jure & de facto!

Surely when the title of a vassalized ruler is usurped, their vassals should have their vassalage transferred to the liege of their former liege? (in this case me, the one doing the usurping)

I guess this is a bug?
I have to confess, I don't think I've ever usurped the title of one of my vassals before in this way. (it's a fairly unusual situation for a ruler to gain a claim on one of their vassals' titles)

 

[Ultima_Ratio]

Just revoke it if you have a claim on it. I'd imagine that usurping within the same realm (which requires a strong claim anyway) is only really meant for vassals and this is an oversight.

 

[StarSword]

Just revoke it if you have a claim on it. I'd imagine that usurping within the same realm (which requires a strong claim anyway) is only really meant for vassals and this is an oversight.

Agreed, I didn't even know the Usurp button was available for lieges against vassals. You need to use the Revoke Title button on the diplomatic menu.

 

[Matthias_Wlkp]

Got the same thing today. Definitely a bug.