The NetCoalition, which includes AOL, eBay, Google, Facebook, Twitter and Yahoo, is still opposed to the anti-piracy bill pending in Congress even with a series of changes unveiled on Monday.

Markham Erickson, executive director of the coalition, said in a statement that while “some provisions have improved,” the changes also create “new problems in other places and fails to correct some of the original concerns we have raised since the start of the debate.”

Erickson noted that the bill still allows content holders to pursue their own action against payment processors and ad firms that do business with so-called “rogue sites.” He also said that the scope of the bill is still to broad, as the definition of a “search engine” is still “vague and arbitrary.”

He also said that the bill “exposes an Internet platform to liability if only one page contains illegally distributed content.” The coalition continues to have concerns that the legislation would harm the architecture of the Internet with a provision that would force Internet providers to take steps to block sites that are dedicated to infringing activities.

Meanwhile, potentially significant opposition is coming from Wikipedia. Its founder, Jimmy Wales, is surveying users on whether they should stage a “strike” in which the site would be blanked out in protest of the legislation. It would be similar to a strike that Wikipedia staged in Italy as that country’s government considered a law which, in Wales’ words, “would infringe on their editorial independence.” The parliament backed down.

“As Wikipedians may or may not be aware, a much worse law going under the misleading title of “Stop Online Piracy Act is working its way through Congress on a bit of a fast track,” Wales wrote in a post.

He added, “There are obviously many questions about whether the strike should be geotargetted (US-only), etc. (One possible view is that because the law would seriously impact the functioning of Wikipedia for everyone, a global strike of at least the English Wikipedia would put the maximum pressure on the US government.) At the same time, it’s of course a very very big deal to do something like this, it is unprecedented for English Wikipedia.”