So What’s the Problem?
Unit                     Company                 Product
Unit                    Company
Unit                    Product
Galaga99            UW                  Galaga99       databases
Bingo                 UW                  Bingo             databases
No problem so far. All local FD’s are satisfied.
Let’s put all the data back into a single table again:
Galaga99                  UW                      databases
Bingo                       UW                      databases
Violates the dependency:   company, product -> unit!