Immigration authorities are cracking down on requirements and conditions for H-1B visas, which many employers in the tech industry use to hire skilled talent from other countries.

U.S. Citizenship and Immigration Services sent a letter to the Senate Judiciary Committee announcing plans to stop allowing spouses of H-1B visa holders to apply for work permits. That reverses a 2015 rule that made spouses eligible for permits to work in the U.S.

The agency also said it is working on a plan to rescind the International Entrepreneur Rule, an Obama-era policy that allows foreign-born founders to build their startups in the U.S. for several years. That rule was implemented as a workaround after a true “startup visa” — which would have created an official visa category for foreign-born entrepreneurs — died in Congress.

USCIS is also revising the definitions of “specialty occupation,” “employment,” and “employer-employee relationship” — three criteria that companies must prove to USCIS when petitioning for H-1B visas. USCIS Director Francis Cissna said these changes are intended to “better protect U.S. workers and wages” in the letter to the Judiciary Committee.

All of these changes are in response to President Donald Trump’s “Buy American, Hire American” executive order issued a year ago. The order seeks to reduce fraud and abuse of work visas and encourage companies to develop domestic workforces.

In February, USCIS issued a memorandum expressing its intention to collect more information and documentation from so-called “outsourcing” firms to curb abuse of the H-1B visa lottery system.