Broken Lines in Design Patent Drawings
A broken line disclosure is understood to be for illustrative purposes only and forms no part of the claimed design. Structure that is not part of the claimed design, but is considered necessary to show the environment in which the design is used, may be represented in the drawing by broken lines. This includes any portion of an article in which the design is embodied or applied to that is not considered part of the claimed design. When the claim is directed to just surface ornamentation for an article, the article in which it is embodied must be shown in broken lines.
Below is an example of Box Lid with Handle design. If broken or stippled lines are not there, it is not clear where this design is going to be used. So, it will be a Disembodied Design. Therefore, it is necessary to show the environment where this design is going to be used and as it is not claimed, it should be shown by broken lines.