( CNN ) -- A bill moving through Congress is intended , on its surface at least , to do something relatively simple : Crack down on the illegal pirating of movies , music and other copyrighted material . But a major online backlash has evolved , with everyone from lawmakers to Web-freedom advocates to some of technology 's biggest players calling it a greedy and dangerous overreach that could have a chilling effect on free speech and innovation . Google , Yahoo and Facebook are among the Web heavyweights who have joined the chorus against the Stop Online Piracy Act ( SOPA ) , which backers hope to have ready for a vote by the end of the year . Its intent is to help put a stop to foreign websites that illegally post , and sometimes sell , intellectual property from the United States . Federal law-enforcement agencies would be empowered to shut down those sites , and cut off advertising and online payments to them . `` The Stop Online Piracy Act helps stop the flow of revenue to rogue websites and ensures that the profits from American innovations go to American innovators , '' Rep. Lamar Smith , a Texas Republican , chairman of the powerful House Judiciary committee and the sponsor of the plan , said when the bill was introduced last month . `` The bill prevents online thieves from selling counterfeit goods in the U.S. , expands international protections for intellectual property , and protects American consumers from dangerous counterfeit products. `` Its supporters include some powerful lobbying groups , including the Motion Picture Association of America , the pharmaceutical industry and the U.S. Chamber of Commerce . On the other side are Web-freedom advocates , who were quick to say the effort goes too far . And this week , in the wake of a Wednesday hearing on the plan , that discontent grew louder and more widespread . `` Our government is tampering with its basic structure so people will maybe buy more Hollywood movies , '' says an animated video by Kirby Ferguson , the New York filmmaker behind the Web video series `` Everything Is a Remix , '' that is making the rounds online . `` But Hollywood movies do n't get grassroots candidates elected . They do n't overthrow corrupt regimes , and the entire entertainment industry does n't even contribute that much to our economy . The Internet does all these and more . '' Perhaps tellingly , that video was made in response to an earlier bill proposed in the Senate , which has since been put on hold by its sponsor . Ferguson has since added a message at the end of the video saying the issue has `` gotten much worse . '' Some critics fear that enforcement of the act is ill-defined and could allow federal authorities to go after sites that do n't set out to illegally broadcast or sell content . For example , advocates say , YouTube has housed important content , like video of political unrest in places like Egypt and Iran where government crackdowns had otherwise blocked media access . But YouTube also is home , albeit against its will , to music videos , movie clips and other content posted without the intent of its creators . Under SOPA , they say , a fledgling YouTube could have been shut down because of those posts . This week , a letter opposing the House and Senate bills was sent to Congress , signed off on by AOL , eBay , Facebook , Google , LinkedIn , Mozilla , Twitter , Yahoo and Zynga . `` We support the bills ' stated goals -- providing additional enforcement tools to combat foreign 'rogue ' websites that are dedicated to copyright infringement or counterfeiting , '' the letter reads . `` Unfortunately , the bills as drafted would expose law-abiding U.S. Internet and technology companies to new uncertain liabilities , private rights of action and technology mandates that would require monitoring of websites . `` We are concerned that these measures pose a serious risk to our industry 's continued track record of innovation and job-creation , as well as to our nation 's cybersecurity . '' To coincide with Wednesday 's committee hearing , many websites devoted themselves to drawing attention to the debate . Blog platform Tumblr blacked out images in users ' posts with a message urging users to `` Stop The Law That Will Censor The Internet ! '' A post on Tumblr 's staff blog claimed users flooded House lawmakers Wednesday with 87,834 phone calls protesting the bill . The backlash seems to be spreading to the halls of Congress . On Thursday , House Minority Leader Nancy Pelosi , D-California , announced her opposition to the plan on Twitter . `` Need to find a better solution than # SOPA # DontBreakTheInternet , '' she wrote , using hashtags that opponents have used to show their disapproval on the site . Even Pelosi 's opponents from the other side of the ideological aisle agreed with her . Influential California Republican Rep. Darrell Issa joined other conservative lawmakers , including presidential candidates Michele Bachmann and Ron Paul , in opposing the proposed law . `` I do n't believe this bill has any chance on the House floor , '' Issa told The Hill on Wednesday . `` I think it 's way too extreme , it infringes on too many areas that our leadership will know is simply too dangerous to do in its current form . ''
Bill to fight online piracy being hit by huge Web-freedom backlash . The Stop Internet Piracy Act is intended to protect U.S. intellectual property . Web-freedom advocates say it 's too broad and could be used to shut down legit sites . Score: 6