In their appeals, several of the criticised universities cited an increasing need for internationalisation as the main reason for this demand.
"Internationalisation lies in the nature of science, particularly natural science, and is encouraged in every other context," wrote the University of Gothenburg.
The universities also pointed out that when hiring for more advanced teaching and research positions, Sweden's current regulations demand that experts within the field evaluate all applicants.
"An application written in Swedish will delay the recruiting process in those cases where international expertise is needed to assess scientific and pedagogic skill," wrote the Royal Institute of Technology (KTH).
JO has looked into the case, and concluded that the requirement that candidates submit their job applications in English is in violation of Sweden's language laws.
The language law, which came into effect on July 1, 2009, dictates that Swedish be used as the official language in the country, particularly by public institutions.