What happens to Blender IK bones in Mecanim?

As the title says, i wanna know what happens to bones that do not deform the mesh (like IK bones) when imported into unity and used in Mecanim. I am a complete newbie in terms of animations in Unity so i really wanna know how this works so i can prepare my character in blender before animating/importing it.

You don’t need to worry about that. If the bones do not deform the mesh in Blender, they will not do so in Unity either. They will stay, but they won’t do anything. They won’t affect the model or its animation in any way, you will just have some extra bones in the rig.

Adding this in for the info.

IK is only supported by Unity Pro. Placing an IK rig into free version will strip out the IK and will use FK (Forward Kinematics) to derive the movements instead.

Most other fangled stuff in Blender is unsupported by Unity as of yet.