Thanks to the work of the Swiss Embassy, the American State Department and the Administrations of the United States and Iran, Xiyue Wang, a researcher and history student at Princeton who was arrested in 2016 and sentenced to 10 years in prison in Iran for espionage (charges which he has always denied) and Professor Massoud Soleimani, an Iranian scientist convicted of violating U.S. sanctions and arrested in 2018, were released on December 6th and returned to representatives of their respective governments and trips back to their respective homes.
(The Morning Call, US and Iran Swap Prisoners in Rare Diplomatic Breakthrough, by Farshid Motahari and Eliyahu Kamisher, December 7, 2019)