Through its Amazon Marketplace, the retailer enables 3rd-party firms to offer items for sale at Amazon.com. Overall, merchants are satisfied with this. But sometimes, Amazon competes with these merchants and makes it tough for them to succeed.

As Don Reisinger, writing for CNET News, reports: ” Amazon’s Marketplace has exploded over the last several years, and accounts for a surprisingly large chunk — around 10 percent — of the retail giant’s total revenue. The company takes a piece of the revenue generated on each sale, but leaves the lion’s share to the individual retailer. According to the Wall Street Journal, Amazon told it that sales are up in the Marketplace, and sellers can expect a 50 percent increase in sales just by joining the Marketplace. At the same time, Amazon has made it clear that it’s not necessarily partnering with Marketplace vendors, and has from time to time, offered the same products. The issue, according to retailer Brad Howard of CuffCrazy.com, who spoke to the Wall Street Journal, is that when Amazon joins the fray, ‘it’s pretty much impossible to compete.'”

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