Skilled foreign-born workers are critical to firms. Yet political or cultural factors can lead governments to restrict skilled immigration. To what extent, and how, does lobbying help firms overcome immigration barriers? This study explores these questions by focusing on the case of U.S. firms and an exogenous increase in H-1B high-skilled visa denial rates following the election of Trump in 2016. I construct an original firm-level dataset that combines the universe of U.S. temporary high-skilled visa petitions through 2017 with firms’ immigration lobbying reports and financial information. Leveraging the data and text analysis, I document key stylized facts about U.S. immigration lobbying behavior: who, how, and what firms lobby. Using a difference-in-differences design, I find that firms’ bureaucratic lobbying under the Trump administration reduced denial rates on their visa petitions by at least 4.5 percentage points. These findings bridge existing research on immigration policymaking and lobbying effectiveness.