RALEIGH, N.C. — Advocacy groups said Monday they will ask an appeals court to expand a favorable ruling on transgender restroom access to cover people across North Carolina.

They filed their notice of appeal after a federal judge's preliminary ruling said two transgender students and an employee must be allowed to use restrooms matching their gender identity at University of North Carolina campuses.

On Friday, U.S. District Judge Thomas Schroeder wrote that the plaintiffs have a strong chance of proving their arguments that the North Carolina measure known as H.B. 2 violates Title IX, a federal law prohibiting gender discrimination in educational institutions. The case is scheduled for trial in November.

However, Schroeder said the plaintiffs haven't shown they are likely to succeed on a claim that the state law violates their constitutional equal protection rights. He reserved judgment on another constitutional claim related to due process.

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In their appeal, the transgender plaintiffs will ask the 4th Circuit Court of Appeals to rule in their favor on the equal protection claim — which would apply to all transgender residents in the state and not just those at just educational institutions, said Chris Brook, legal director for the North Carolina chapter of the American Civil Liberties Union.

"A ruling on equal protection or any other constitutional grounds could fully eviscerate H.B. 2 and its unnecessary bathroom provisions," Brook said in an interview, though he added that his clients were still "thrilled" by Friday's ruling.

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The North Carolina law passed in March requires transgender people to use restrooms in schools and many public buildings that correspond to the sex on their birth certificates, rather than their gender identity. It also limits statewide anti-discrimination protections for gay, lesbian, bisexual and transgender people.

The state's Republican leaders, who are defending the law in court, have said the measure is needed to protect people's privacy in restrooms.

Challengers to the law, who also include Lambda Legal and U.S. Justice Department lawyers, argue that it's a discriminatory law and that bathroom privacy is protected by existing trespassing and voyeurism laws.

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