Protective case for an electronic device

FIG. 1 is a back perspective view of a protective case for an electronic device showing our new design;

FIG. 2 is a back plan view thereof;

FIG. 3 is a front plan view thereof;

FIG. 4 is a top elevation view thereof;

FIG. 5 is a bottom elevation view thereof;

FIG. 6 is a right side elevation view thereof; and,

FIG. 7 is a left side elevation view thereof.

The broken lines indicate unclaimed portions of the article that form no part of the claimed design.