It is and isnt. The inventors Brewerie Riegele sold the rights to Paulaner Brewerie, then it became famouse, big legal fights about the rights came but spezi now is a collective term (Gattungsbegriff) to all cola/lemonade mixes. So now there are the big Paulaner Spezi and Spezi Original from Riegele, that dominate it buuut every brewerie that hold itself to something has their own version