https://www.reuters.com/article/us-usa-immigration-court/tech-giants-back-legal-challenge-to-trumps-foreign-worker-restrictions-idUSKCN2561WB >Top U.S. tech firms including Amazon.com Inc and Facebook Inc filed a legal brief on Monday backing a challenge to U.S. President Donald Trump's temporary ban on the entry of certain foreign workers to preserve jobs for Americans during the coronavirus pandemic.