Entirely up to each business. You could spread the increase in costs out to all clients and hope that the increase on those that stay makes up for the decrease

Entirely up to each business. You could spread the increase in costs out to all clients and hope that the increase on those that stay makes up for the decrease from those that leave. You could charge it all to MS who is likely your biggest customer. Or any combination in between. It's a calculation that each company would have to make for itself.