Which property is the unique identity for a company beside DB name

Hi everyone,

I would like to distinguish the company, I know for a company DB name is unique,however, database can be restored from other company database.

is there any information for one company cannot be changed from SAP UI once it created, and when company DB restored from other company DB, I can compare the new value with last I saved value and know this database different with the original company database. I have considered about company name, in different company DB the company name different, but company name can be changed from SAP B1 Company details window.

In one words, I want to know which is the company level identity.

Thinks in advance!

Kathy