Multiple sources have told National Journal that Verizon, the nation's second largest telecommunications carrier, may seek to overturn the historic open Internet rules to be approved by the Federal Communications Commission Tuesday morning. Sources said the option is on the table, but cautioned that no final decision has been made. The company will review the details of the new “network neutrality” rules set for adoption by the agency's three Democratic regulators to gauge its next move.

The new regulations, which seek to prevent broadband providers from degrading or blocking competing online services, will be enforceable and could subject companies to fines, injunctions and forfeiture, senior agency officials told reporters Monday. The initiative is considered vulnerable to a court challenge because Genachowski is seeking to treat broadband as a lightly regulated “information service” even though a federal appeals court in April tossed out this approach. The FCC now says it has developed a more solid legal foundation, with the details to be disclosed today.

Read the full National Journal story, “BREAKING: Verizon Weighing Lawsuit Against FCC.”