Danish police are investigating potential leaks of information regarding credit card use by politicians, celebrities and members of the Danish royal family to a magazine.
Police have charged, but not placed in detention, a former male employee at International Business Machines with leaking card data to the magazine Se & Hor.
The International Business Machines employee was contracted to work for Nordic card payments firm, Nets.
Police say Nets, Se & Hor and IBM are cooperating with their investigation.
Bent Isager-Nielson, chief superintendent of Copenhagen police, said: "The suspicion is that Se & Hor in the period 2008-2012 has received information about people’s credit card transactions from Nets."
Former Danish Prime Minister Lars Lokke Rasmussen and members of the royal family were allegedly among those whose card use was monitored.
Seven Se & Hor employees have been ordered to take vacations during the probe, whilst former editor Henrik Qvortup quit his job as a political commentator for TV2 last week following the launch of the investigation.
Nets systems handled 6bn credit card transactions supporting 33m payment cards in 2013, prompting Nets country manager Susanne Bronnum to suggest protecting this data is a difficult challenge.
"It is not possible to guard oneself completely against people who are abusing their trusted position to commit crimes."
In March 2014, a consortium comprising Advent International, Bain Capital and Danish pension fund ATP agreed to buy Nets Holding for DKK17bn ($3.1bn).