Opponents of Internet surveillance, including groups from both the left and right of the political spectrum, plan a day of online protest tomorrow (Feb. 11) against the U.S. National Security Agency (NSA) and its British equivalent, GCHQ.

Calling the protest "The Day We Fight Back," organizers are planning marches and lectures worldwide, and are also providing software tools for website owners to add banners, and social-media users to overlay profile photos, in support of the effort.

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The effort hasn't garnered any overt support from Silicon Valley tech companies, who have formed their own anti-NSA coalition, Reform Government Surveillance, to directly influence congressional lawmakers.

Yet a Facebook spokeswoman told Tom's Guide that Facebook would be participating in The Day We Fight Back, and said the company's support would include a blog post. Another source suggested the Reform Government Surveillance group as a whole — it includes AOL, Apple, Facebook, Google, LinkedIn, Microsoft, Twitter and Yahoo — would be on board.

"We aren't going to let the NSA and its allies ruin the Internet," states a manifesto posted on the website of the Electronic Frontier Foundation, one of the Day We Fight Back's organizers. "The world will demand an end to mass surveillance in every country, by every state, regardless of boundaries or politics."

Organizers are hoping for a repeat of the successful 2012 campaign against the Stop Online Piracy Act (SOPA) and the PROTECT IP Act (PIPA), two complementary congressional bills that would have given American law enforcement drastic powers to crack down on software, music and movie piracy.

Yet Google and Wikipedia, two organizations that were crucial to the success of the anti-SOPA/PIPA effort, have not attached their names to the effort.

Most of the Day We Fight Back's backers are political, human-rights and Internet-policy groups such as the ACLU, Greenpeace, Demand Progress, the Libertarian Party, Ron Paul's Campaign for Liberty, Human Rights Watch and Amnesty International. Mozilla, Reddit and Tumblr (but not Tumblr's parent company, Yahoo) are among the few tech-industry sponsors.

The Reform Government Surveillance coalition first appeared in October with an open letter to congressional leaders, asking for greater leeway for private companies to disclose what kind of national-security-related requests for information they receive from U.S. government agencies.

Last week, having reached an arrangement with the Justice Department and the Director of National Intelligence, Facebook, Google, Microsoft and Yahoo finally made such disclosures. The Reform Government Surveillance coalition also hired a lobbying firm to speak for it on Capitol Hill.