How to tell if a company actually sponsors, using public data

Before you spend hours applying, check the public record. The Department of Labor LCA disclosure data and the USCIS H-1B employer data hub show which employers filed H-1B petitions, how many, and at what wages. A company that filed dozens of petitions last year is a very different bet from one that filed zero. This beats guessing from a careers page. Which data source have you found most useful?