Nine held in Sweden on suspected insider trading in Fortnox and Tethys Oil
Published by Global Banking and Finance Review
Posted on September 2, 2025
2 min readLast updated: January 22, 2026

Published by Global Banking and Finance Review
Posted on September 2, 2025
2 min readLast updated: January 22, 2026

Nine individuals were arrested in Sweden for insider trading involving Fortnox and Tethys Oil stocks, linked to takeover offers in 2024 and 2025.
STOCKHOLM (Reuters) -Swedish police apprehended nine people on Tuesday on suspicion of gross insider stock market trading in 2024 and 2025, ahead of the publication of takeover offers for two companies listed on the Stockholm bourse, the Economic Crime Authority said.
The suspected insider trades were made in the shares of Tethys Oil, which was subject to a takeover in September of last year, and fintech Fortnox, which was bought after an offer in March this year, an agency spokesperson said.
The agency said several persons with mutual connections repeatedly traded large sums in a coordinated manner, based on what it suspects was leaked information on expected bids.
"It is insider trading on a level we have barely seen before," Prosecutor Jonas Myrdal said in a statement, adding that Tuesday's police action followed a long investigation and included the seizure of electronic devices.
A spokesperson for Tethys Oil said the company had no indication or reason to believe that the matter concerned any of its current or former employees.
A Fortnox spokesperson declined to comment.
Tethys Oil and Fortnox were delisted in January and July, respectively.
(Reporting by Anna Ringstrom, editing by Terje Solsvik and Bernadette Baum)
The suspects were arrested on suspicion of gross insider stock market trading in 2024 and 2025, related to takeover offers for Tethys Oil and Fortnox.
The insider trading case involves Tethys Oil, which was subject to a takeover in September of last year, and fintech Fortnox, which was acquired after an offer in March this year.
Prosecutor Jonas Myrdal stated that the insider trading was on a level rarely seen before, indicating the seriousness of the investigation.
A spokesperson for Tethys Oil stated that the company had no indication or reason to believe that the matter involved any of its current or former employees.
Tethys Oil was delisted in January, while Fortnox was delisted in July.
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