There are an estimated 200,000 probationary workers — generally employees who have less than a year on the job — across federal agencies.

A federal judge in San Francisco on Thursday found that the mass firings of probationary employees were likely unlawful, granting some temporary relief to a coalition of labor unions and organizations that has sued to stop the Trump administration’s massive trimming of the federal workforce.

U.S. District Judge William Alsup instructed the Office of Personnel Management to inform certain federal agencies it had no authority to order the firings of probationary employees. The ruling is