The QR codes first caught the public’s attention late last year when cemetery-goers noticed the discreet stickers pasted on the headstones of their loved ones. When scanned, the codes show the name of the person buried and the location of their grave in the cemetery.

The 5 x 3.5cm (1.95 x 1.2 inch) stickers were placed on old and new graves at the Waldfriedhof, Sendlinger Friedhof and Friedhof Solln cemeteries.

Bernd Hoerauf, who oversees the management of Munich’s cemeteries, told the New York Times: “It’s really strange. We thought, ‘What could be the sense of this kind of sticker?’”

As the mystery deepened, some social media users claimed it was a viral marketing stunt with others suspecting vandals or even a tech-savvy artist making a statement.

The mystery unfolds

Removing the codes (due to the sticky adhesive) was costing the cemeteries a fortune, so police were called in to investigate. It turned out a local gardening business, whose name has not yet been made public, was behind the stickers.

Alfred Zanker, a senior manager from the company, explained the stickers helped his employees keep track of which headstones had already undergone maintenance. His company has now been tasked with the clean-up. “We are a large company. Everything has to happen in an orderly manner,” he told Munich newspaper Süddeutsche Zeitung.

According to the German newspaper the repair process is quite complex as the headstone has to be dismantled and taken away. Afterwards, the stain is sanded down and the stone then put back in place.

“Due to the high number of cases, police estimate the total damage to be around €500,000.”

Cemeteries in Munich do actually permit the use of QR codes so that loved ones can have access to online memorials filled with photographs and other digital keepsakes. However, those codes are normally applied to the gravestones via an etching or metal plate.