Yes, the new patent can only cover the new improvement. The issue is that doctors keep proscribing the newer, slightly improved methods. Trying to evergreen o

Yes, the new patent can only cover the new improvement. The issue is that doctors keep proscribing the newer, slightly improved methods. Trying to evergreen on purpose is also dangerous since your competitor can patent an improvement on your invention. I somewhat doubt it is a purposeful strategy. But rather it just reflects the iterative nature of invention.