Both police and the Bahlsen managers are stumped by the theft of the biscuit-shaped logo, which has hung on the building untouched since 1913.
"We don't know. Anything is possible," a company spokeswoman said on Friday. "We're completely shocked."
Company chairman Werner M. Bahlsen has put up a reward of €1,000 for any information leading to the recovery. Incredibly, however, the investigation has been made more difficult by the fact that no-one knows exactly when the biscuit was stolen.
One Bahlsen worker reported seeing the biscuit three days into the New Year, but it was only reported missing last Monday.
What is clear is that the operation could not have been easy. The biscuit weighs 20 kilos, is about 50cm tall, and is suspended at a height of some five metres inside a large pretzel between two bronze men. The thief or thieves must have used a long ladder, or have been adept climbers.
"You can't just put it under your arm," said the spokeswoman.
On top of that, Bahlsen's headquarters are on a busy road where cars pass virtually 24 hours a day. Around 250 employees also regularly enter and leave the building.
The motive also remains a mystery - the logo, part of a facade sculpture, is not made of real gold, but gold-plated bronze, worth about €100 if sold for scrap. Bahlsen would not say how much the logo is actually worth. "We can't say anything about its material value," the spokeswoman said. "It's sentimental value is what counts for us, and that is high."