Since the end of January, Ryan Helgeson, a Chicago-based immigration attorney, has noticed an unusual trend: He’s been getting significantly more pushback from US Citizenship and Immigration Services as he files employment visa petitions on behalf of his foreign-born clients.Helgeson’s firm, McEntee Law Group, represents tech workers who hope to emigrate or remain in the US by way of visas granted for specialty occupations or extraordinary abilities. On average, Helgeson’s firm files 50 to 75 vi...