The remaining original manufacturer's marks prove that this mark belonged to a decoration studio that appears to have mainly targeted the French market. This studio was of course not located in or around Carlsbad; they merely implied that they used the same decoration style. And they were not the only one; just take a look at the probably related mark M120722, which is claimed to have been established 1901.

M060619a
Circular "KARLSBADER WERTARBEIT" containing "GEGR. 1921", all flanked by the initials "DW" .

M060619b
"FINE PORCELAIN" with "PORZELLAN MANUFAKTUR" surrounding "KARLSBADER WERTARBEIT" and "GEGR. 1921".