The ornamental design for a clip for writinginstrument, as shown and described.
FIG. 1 is a perspective view of the invention;
FIG. 2 is a front view of the invention;
FIG. 3 is a side view of the invention;
FIG. 4 is another side view of the invention showing the side opposite that shown in FIG. 3;
FIG. 5 is a back view of the invention;
FIG. 6 is a top view of the invention; and,
FIG. 7 is a bottom view of the invention.
The features of the clip for writing instrument shown in broken lines in FIGS. 1–7 are for environmental purposes only and form no part of the claimed design.