Netflix, Reddit, Vimeo and dozens of other Internet companies are holding a symbolic "slowdown" today in protest of Federal Communications Commission Chairman Tom Wheeler's controversial net neutrality proposal.
Twitter was a last-minute addition to the roster of sites which are holding the protests of the FCC proposal, which would allow broadband providers to charge companies like Netflix for prioritized, fast-lane access to consumers.
Sites taking part in the protest aren't actually slowing down, but will display a spinning icon to symbolize what could happen if the FCC moves forward with the plan. They'll also include a link to help people comment to the FCC about the proposal.
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A Twitter spokesman said the company isn't planning to put an icon on its site, but would "participate in other ways."
Next week marks the end of the FCC's comment period on its controversial proposal.
Earlier this week, House Democratic Leader Nancy Pelosi of California delighted some net neutrality proponents by formally throwing her support behind the FCC resolving the net neutrality issue by re-regulating Internet lines under Title II of the Communications Act.
Broadband providers are opposed to that idea and their supporters are also expected to ratchet up their public lobbying against the idea as the FCC's comment period closes.
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—By Amy Schatz, Re/code.net.
CNBC's parent NBCUniversal is an investor in Re/code's parent Revere Digital, and the companies have a content-sharing arrangement.