The incident took place at 7:30 pm on Saturday, May 8 at Selfridges in Oxford Street, London.
Police said they were called to reports of a fight at the store.
A Met Police spokesman said: “Police were called at approximately 7:35pm on Saturday, 8 May to reports of a fight at a store in Oxford Street, W1.
“Officers attended the scene and found a male with a stab injury to the leg.
“He has been taken to hospital for treatment – his condition is not thought to be serious.”
MORE TO FOLLOW