The National Labor Relations Board’s General Counsel has issued an advice memo stating that drivers for Uber Technologies are independent contractors and not employees.

Its advice memo, dated April 16 and released May 14, pertains to three separate cases before the NLRB alleging Uber wrongfully terminated drivers as well as hampered unionization efforts of Uber drivers; the regional offices were urged to dismiss the cases.

The general counsel cited the January NLRB’s SuperShuttle ruling in which the board overturned an Obama-era decision in 2014 on who qualifies as independent contractors.

The general counsel found the Uber drivers had significant entrepreneurial opportunity and control over their own work, concluding “these and other facts strongly support independent-contractor status and outweigh all countervailing facts supporting employee status.”

Not appealable. While determinations of the board itself can be appealed, “decisions by the general counsel’s office not to issue an unfair labor practice are not subject to [federal] judicial review,” Richard Reibstein, a partner representing employers at Locke Lord LLP’s New York City office, told Bloomberg Law.

The general counsel’s memo follows an opinion letter issued by the US Department of Labor concluding that workers who provide services to consumers through an unidentified virtual platform are independent contractors under the Fair Labor Standards Act, not employees of the company.