disabling IK properties from a control rig

Hi guys, 

I'm going to be a writing a plugin to channel all my own joint rotation matrix
information onto a control rig - but when I set matrices for each bone, I don't
want the IK solver to change anything else.

So how do I disable all IK properties from a control rig, so I can use only FK?
(Or is there a different approach I should be taking?)

thanks.