Anne Metzger, head of the firm AM Immobilien Consulting, claims that Munich's stylised "M" logo, chosen by more than 50,000 people following a national design competition, is very similar to the one that she trademarked in 2006. 

She has claimed that it is "defamatory" to her firm and now has filed an opposition at the German Patent and Tradmark office.

"We [the company] are also active in Munich, where I can now not distribute any business cards with my logo because it is so similar to the Olympics," said Metzger.

Metzger also claims that when she complained to Munich 2018 about the similarities they demanded·€2,000 (£1,771/$2,870) in damages.

But Munich 2018 are refusing to allow the controversy to derail their campaign as it approaches its conclusion at the International Olympic Committee (IOC) Session in Durban on July 6, where they will face rivals Annecy and Pyeongchang. 

They claim that they registered their logo correctly under Germany law and they have not broken any regulations. 

There is also confusion about why Metzger has filed her claim now when - win or lose - Munich's logo will very soon become redundant. 

Normally, even after cities are awarded the Games, they launch a competition to find a new logo.

"The request by a real estate agency from Berlin will in no way effect the momentum which Munich has built up in the final days towards the IOC decision in Durban," said a Munich 2018 spokesman.

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