lift the link, don't rub it in...
I've found spray-on/cream leather cleaners to perform insufficiently when it came to the removal of certain contaminants/blemishes from leather seating surfaces (ie. gel/ballpoint pen marks, lipstick, nail-polish, rubber-scuffs, tar/asphault marks, etc').
Rubbing alcohol (isopropyl) works well in removing ink from fabrics/leather.
Also, try an ink/lipstick remover for leather, it's a wax-like pen 'stick'. It's readily available just about everywhere (in-store, specialty shoppes, online, etc')!