A company sign is a so-called trade designation. In contrast to the trademark, a company sign directly characterizes a company, but only indirectly characterizes the goods and services provided by said company.
A company sign may be the name of a business establishment (e.g. "Bakery Miller"), the firm under which a merchant runs his business (e.g. "Sailing School Stiff Breeze"), or a so-called establishment designation (e.g. "Crown Hotel"). Under certain conditions also so-called business insignia (e.g. the famous color of the delivery vans of a parcel delivery service, or the button in the ear of a toy animal) may be protected.
An essential difference over the registered mark resides in that a company sign is not a registered right, but that the protection thereof starts with the use of the same, provided that the designation is distinctive and has acquired secondary meaning. The protection of a company sign is, therefore, only limited to the territory where said criteria are fulfilled, whereas the protection of a registered mark takes effect in the whole Republic of Germany as soon as it is registered, even if it has not been used as yet.