#4 Rob Kalin

Rob Kalin co-founded Etsy, an e-commerce website focused on handmade or vintage items as well as art and craft supplies. The site was launched on June 18, 2005, and he resumed his role as CEO from December 2009 until July 2011. In Etsy's first year, it attracted attention for frequently adding new tools and functionality to the site to help sellers gain exposure and traffic, including Adobe Flash-based visualizations and a taxonomy of categories with tags. It passed $1.7 million in sales in May 2007.

In February 2008, trouble at eBay, including a strike by some dissatisfied sellers, brought speculation that Etsy could be an increasing competitor. At the same time, however, some Etsy sellers expressed unhappiness with how it was handling complaints about stores. At the time, a comparison of the two websites included complaints that on Etsy, items are difficult to find, the interface "feels slow", and the buying and selling process is United States-centric. In July 2008, Rob Kalin ceded the position of CEO.

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