Inventors of the internet and Apple's co-founder have been part of a high-profile group of internet pioneers demanding a vote on net neutrality be stopped in the United States.
Net neutrality is the idea that all content on the internet is equal.
The US Federal Communications Commission (FCC) unveiled plans in November to repeal landmark 2015 legislation which protected that concept.
The rules, pushed for by then-president Barack Obama, barred providers from slowing down or blocking access to content, and charging more for better access.
The Donald Trump-appointed FCC chief Ajit Pai said the commission would vote on Thursday (local time) to overturn what he called the "heavy-handed" regulation.
World Wide Web inventor Tim Berners-Lee and Apple co-founder Steve Wozniak were among the 21 signatories of a letter addressed to politicians who said the upcoming vote was, "based on a flawed and factually inaccurate understanding" of the internet.
Thursday's FCC vote would be on the Restoring Internet Freedom Order, which the letter said was full of "misunderstandings".
"The technically incorrect proposed order dismantles 15 years of targeted oversight from both Republican and Democratic FCC chairs, who understood the threats that internet access providers could pose to open markets on the internet," the letter said.
Other signatories included Mitchell Baker, the chairwoman of Mozilla, and several 'internet pioneers' such as Scott O Bradner, Vinton C Cerf and Stephen D Crocker.
"The FCC's rushed and technically incorrect proposed order to abolish net neutrality protections without any replacement is an imminent threat to the internet we worked so hard to create," the letter said.
"It should be stopped."
The plan to repeal had been welcomed by internet service providers (ISPs) in the US like Verizon, AT&T and Comcast, who could get sweeping powers to decide what web content consumers get, and at what price.
"The proposed order removes long-standing FCC oversight over internet access providers without an adequate replacement to protect consumers, free markets and online innovation," the letter said.
Internet giants Netflix, Facebook and Alphabet, as well as smaller companies AirBnb, Reddit, Tumblr, Etsy and Twitter, had also urged the FCC to scrap the plan.
The FCC has three Republican and two Democrat commissioners, so the move is all but certain to be approved on Thursday.
Australia does not have any laws on net neutrality, but experts say strong competition among local providers, along with strong consumer laws, could protect Australians.