Microsoft opposes US labour board ruling on contract worker rights

A Microsoft logo is seen a day after Microsoft Corp's $26.2 billion purchase of LinkedIn Corp, in Los Angeles, California, U.S. June 14, 2016. REUTERS/Lucy Nicholson

Microsoft Corp has asked a federal court to throw out a ruling by a US labour board extending the responsibility of companies for contract workers, arguing that the case would have big implications for the technology company. 

An August 2015 decision by the National Labour Relations Board expanded the definition of a "joint employer", which could require more companies to bargain with and have liability for workers hired by contractors.