It is getting tougher for H-1B visa holders to switch jobs. Even if the new job is similar, the United States Citizenship and Immigration Services (USCIS), in several cases, has denied the application by the new employer on various grounds. The most common reason for denial is that the new position does not constitute a ‘specialty occupation’.

from Times of India https://timesofindia.indiatimes.com/world/us/job-hopping-in-us-gets-tougher-for-h-1b-holders/articleshow/69088330.cms