The Federal Communications Commission is expected to publish its final rules on net neutrality in the Federal Register at some point this week.

And while many startups and tech companies that depend on open access to the Internet have cheered those rules, which reclassify Internet Service Providers (ISPs) as public utilities under Title II of the Telecommunications Act, cable and telecommunications industry representatives have already filed several lawsuits that challenge the regulations.

The rewritten regulations prohibit Internet service providers, such as Verizon and Comcast, from blocking, prioritizing content or from creating fast and slow lanes based on a customer’s willingness to pay for services. Opponents of the regulations who filed lawsuits in March, including the U.S. Telecom Association, a trade group representing ISPs, and Alamo Broadband, a Texas-based ISP, say the new rules are too onerous.

Their complaints also say the FCC has expanded beyond its legal authority, and that ISPs' activities should be regulated under the less stringent section 706 of the Telecommunications Act. That section regulates ISPs under rules that do not classify them as common carriers. Telephone companies, for example, are considered common carriers and public utilities which, generally speaking, must operate in the public interest, and less from a profit motive.

“The focus of our legal appeal will be on the FCC's decision to reclassify broadband Internet access service as a public utility service,” Jon Banks, senior vice president of U.S. Telecom said in a statement. “We also support a regulatory approach that relies upon Section 706 authority of the Communications Act, and we do not believe the Federal Communications Commission’s move to utility-style regulation invoking Title II authority is legally sustainable.”

Congressional Republicans had similarly attempted to pass legislation that would have prevented the FCC from using Title II to regulate Internet traffic. However, they abandoned their attempts in February as Democrats mobilized to prevent their bill from moving forward.

This is not the first time that telecommunications companies have wound up in court, squaring off against the FCC. In fact, the new net neutrality rules stem from a lawsuit filed by Verizon in 2011, which challenged the FCC’s original “Open Internet” provision. That provision was established in 2010, stemming from yet another lawsuit with Comcast, and unofficially established rules that emphasaized transparency, and prevented blocking and paid prioritization.

In 2014, a federal appeals court sided with Verizon, seeming to open the door to paid prioritization and content blocking, and provoking an uproar from tech startups, entrepreneurs, and concerned citizens. They flooded the FCC with 2.5 million emails during a public comment period last fall, during its new rules creation process. The uproar even led to some celebrities, such as John Oliver, who devoted a segment of his television show Last Week Tonight to the issue last summer, urging people to write to the FCC to voice their concerns. Tens of thousands of viewers did so.