Is it true that people can get round a patent just by making some minor changes?

Is it true that people can get round a patent just by making some minor changes?

No it is not true. However, the scope of a patent depends on the distance between your invention and the Prior Art. For some inventions it is possible to obtain a very broad patent; for others the protection is necessarily much narrower. It is the scope of the Claims which is crucial, and if the patent is well written the claims will be worded so that anybody who uses your invention will infringe your patent.