A major vendor of POS skimmers ships devices that will print out transaction approved receipts, even though the machine is offline. The skimmer seller is a major vendor on one of the Underwebs most active fraud forums. Being a verified vendor on this fraud forum costs $5,000 annually. The seller can make back his investment with just two sales, and judging from the volume of communications he receives from forum members, business is brisk.”]
Source: https://krebsonsecurity.com/2012/12/point-of-sale-skimmers-no-charge-yet/