I do think Phil has a point here. The Spanish is poorly written, and it is tempting to trim back the verbiage and reduce it to something simpler and, arguably, more appropriate to the language of a legal agreement. However, if you simply remove "imprimir un carácter" I think you are undeniably removing an idea from the text that the writer of the ST has seen fit to include, and I don't think we are really entitled to do that if there is a satisfactory way of retaining it.

"Imprimir un carácter" really amounts here to the idea that this company has its own characteristic way of conducting its business, and that this is the key to its success and prestige. It's not just a question of being successful, but of achieving success though "carácter". This claim should somehow be reflected, I feel. So maybe you could do something like this:

XXXX is a company that has gained a high reputation [...] for/through its distinctive approach to concession business, which has enabled it to create [...].

I think "through" could be used instead of "for", taking "por" as expressing the means by which it has achieved its successes, rather than the quality for which it is admired.

My suggested version really corresponds to "que permite la creación", whereby the subject is of "permite" is "carácter", whereas the subject of "permiten" must be "negocios". However, I think this is a valid liberty, since frankly the latter doesn't make very good sense and the former is, I believe, what they really meant to say.

If you want to stay a little closer to the terms of the original you might say "characteristic approach", but I think "distinctive" sounds better and expresses what I see as the real point of "imprimir un carácter": that this firm does things its own way, not the way others do.