Warranty slips too are being counterfeited; not seldom one receives a complete counterfeit including packaging and service guide. A warranty slip and an original packaging do have their own value but do not replace an authenticity check on the writing instrument itself. Important is not to be impressed by externals, since the combinations range from genuine pen with false slip to false pen with genuine slip. Initialling without a clearly recognisable seller's stamp is therefore no reliable authenticity proof.