This is a developing story and may be updated.

The U.S. Supreme Court on Wednesday sided with corporate interests by ruling against a worker who had sought to band together with other employees to bring forth a class action lawsuit against a company.

It was a 5-4 decision (pdf), with conservatives in the majority.

The case, Lamps Plus, Inc. v. Varela, “hinged on whether courts can allow arbitration as a group even if an agreement does not explicitly provide for the collective arbitration of claims,” Reuters reported.

The company argued that the ambiguous arbitration agreement in Frank Varela’s employment contract meant he could not file a class action suit on behalf of employees whose personal information was exposed in a data breach.

The court “has held that courts may not infer consent to participate in class arbitration absent an affirmative ‘contractual basis for concluding that the party agreed to do so,'” wrote Chief Justice John Roberts for the majority. “Silence is not enough.”