Negative advertising towards Lyft

Mike Isaac’s Super Pumped describes Kalanick’s attempt to “cripple” Lyft through negative advertising:

Uber found ways to mess with Lyft. All around San Francisco, Uber bought street signs and billboards targeting Lyft.  Each billboard showed a large, black disposable razor blade with “Uber” printed on the handle, poised above one of Lyft’s pink, cuddly trademark mustaches. In the text behind the graphic, Uber made its message clear: “Shave the ‘Stache.”

(p.122)