Sergey Skvortskov maintains that he sought legitimate authorisation to transfer potentially sensitive technology.
A Stockholm court on Thursday acquitted Sergei Skvortsov, a Russian-Swedish businessman who was accused of illegally passing on technology to Russian intelligence services.
"The main question in this case is whether the defendant's activities could have led to espionage" but the prosecution "has not been able to prove" that this was his intention, judge Jakob Hedenmo said in a statement.
Prosecutors had requested five years' imprisonment for Skvortsov, who moved to Sweden with his wife in the 1990s and is alleged to have used import-export companies that he ran to transfer electronic equipment.
He was arrested and detained in November 2022, and his trial for "illegal intelligence activities" was held behind closed doors in September. He was released by the court on 9 October, which ruled that there was "no longer any reason" to detain him.
During the trial, the prosecution argued that Skvortsov had acted as a "procurement agent" for technologies that are normally prohibited from being transferred to the Russian military system.
According to experts quoted by the Swedish media, such technology could have been used for nuclear weapons research.
"Russia needs technology. There is a Russian supply system and this system is managed by the intelligence services. Skvortsov and his two companies are part of this system," said prosecutor Henrik Olin during the trial.
In Olin's view, the accused "posed a serious risk to the national security interests of both Sweden and the United States", the two countries targeted by the technology transfers over a period of around ten years.
According to the prosecutor, the technologies exported came mainly from the United States. In 2016, American authorities arrested and tried several people who had supplied the Russian military system with electronic devices, he recalled.
"The analysis of the American authorities is that the defendant followed in their footsteps", Mr Olin said before the trial.
Skvortsov insists that he is a legitimate businessman who sought official authorisation to export his products.
The prosecution argued that the authorisations were intended to "provide him with an appearance of legitimacy" but he used false names of business partners, did not provide information about the exported equipment and provided false information about the end users, according to the prosecutor.
However, Skvortsov's lawyer, Ulrika Borg, argued that the investigation had not proved that the Russian-Swedish national belonged to the Russian system.
"He testified that he was a businessman with numerous contacts in various fields, from vegetables to Roscosmos", she said, referring to the Russian space agency.
"The prosecution has targeted people claiming that they are members of or linked to Russian intelligence, simply because they live in the same street", she added.
Swedish Prime Minister Ulf Kristersson said in July that his country was facing "the most serious security situation since the Second World War".
On Tuesday, he described Russia as one of these threats, pointing out that Moscow took a dim view of Sweden's application to join NATO and its support for Ukraine.