Covenant has a database that is a private holding with 14 other companies which is a form of DAC. I discovered this fact when I examined whatever records that might exist last year. They were the only one to list my failed orientation back in '96. However the lawyer who looked into them stated in the end that Covenant is allowed to be more stricter than federal regulations allowing deaf truckers who pass audio gram. And hire only those who do not need aides to hear. At that point I knew that those 15 companies are not welcome for me to apply to. Its a privately collectively held database. Very effective in defeating or working around the 10 year law that clears DAC.
For me I have nothing in records. So other than that one little blip from a company long forgotten and ancient history (Among others) there is nothing on my end of you did a employer research into my history. However the experience remains and it wont take very long for it to come out on a road test etc.
Social Security holds a lifetime file on me dating back to high school on every penny I earned from whom and I hold my own records equally far back.