Etsy is an online marketplace for handmade goods, where users can set up a storefront and create listings for things they’ve made.  There are over 800,000 active “shops” filled with these handmade goods — far too many for Etsy to monitor manually. Further, because of the eclectic nature of goods listed, it’s difficult to technically filter through the objects listed.

All that means that it’s not feasible for Etsy to proactively prevent listings that may be perceived to violate US copyright or trademark law.  That’s a problem, because  under SOPA, anybody who is a “holder of an intellectual property right harmed by the activities” of even a portion of the site, could serve Etsy’s payment processors with a notice that would require them to suspend Etsy’s service within 5 days. That means that a trademark violation in one of the storefronts could lead to payment suspension across the entire site. Unlike DMCA notices, which should be targeted to specific infringements, payment provider suspensions will likely target entire accounts.  And even if Etsy protests, the bill's vigilante provisions, which grant them immunity for choking off a site if they have a "reasonable" belief that a portion of a site enable infringement, give the payment processors a strong incentive to cut them off anyway.

Like Etsy, Flickr takes copyright issues seriously, and complies with DMCA safe harbor requirements by taking down photos when it gets a valid complaint, establishing a repeat infringer policy, etc.. But it doesn’t proactively monitor its user-generated content for copyright infringement. The language of SOPA is vague enough that an individual or corporate rightsholder could claim this lack of monitoring as “taking … deliberate actions to avoid confirming a high probability of the use of the … site to carry out acts that constitute a violation.” Flickr uses an ad network to place advertisements, and accepts payments for premium accounts. Both of those revenue streams could be suspended in a matter of days by a single complaint, and the process of reactivating them could be long and complex.