I signed a lease for my small business (restaurant). In the lease it states that the liqueur licence stays with the building if I move or default. The lease said I only had to pay the yearly liqueur licence fee. I am currently under a management agreement with the licence until it was able to transfer to my name. I recently found out that this licence had back taxes owed on it by the previous owner of the licence that must be paid prior to transfer. I was unaware of this and it was not stated in the lease that I had to pay those fees as well as my attorney fees for that. I'd really like to get out of (break) this lease and was wondering is this enough to make it null and void and not be sued?

The thing is, it sounds like grounds to me, but what does the landlord say ? If they don't agree, then it will end up in court when either you sue them or they sue you.

If you are merely "renting" the license in a sense, then it is possible the landlord is responsible. I would have a local attorney review them.