I want to know the answer to the following question:
What does a language need to share with the group in order to be classified as Germanic?
All the background I'm provided with is that "All Germanic languages are united by subjection to the sound shifts of Grimm's law and Verner's law which originated in the Proto-Germanic language and define the basic differentiating features from other Indo-European languages.". Is that enough to answer the question?
Answer: no