An Oklahoma manufacturer of prefabricated steel structures will pay more than $430,000 to settle dozens of apparent violations of U.S. sanctions on Iran, federal officials announced this week.

According to the U.S. Treasury Department, Alliance Steel of Oklahoma City outsourced engineering work to an Iranian company at least 61 times between late 2013 and late 2018.

Officials said that when Alliance was unable to handle engineering work in-house, it would outsource the excess work to subcontractors, a process overseen by the company’s then-chief engineer and vice president of engineering — who directed a “significant portion” to a company owned by his brother in Iran.