As far as I'm aware, とある means 'some':
とある会社の従業員
An employee of some company
And just ある can be used to mean the same thing.
Does that give a different level of formality? A more 'direct' or pointed way to referring to the following noun?
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Sign up to join this communityThey are the same thing. However, 「ある」 is more common nowadays, especially among the younger generation.
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