Show that you have a patent
If you show that you have a patent you can avoid unnecessary conflicts.
If you show that you have applied for or received a patent for your invention, it can warn your competitors and discourage them from copying it. That way you can avoid unnecessary conflicts.
If you have stated anywhere, or given the impression, that your invention is patented or is pending a patent, you are obliged to disclose the patent or application number if someone asks for it.