strategic / preferred / listed

[Ksenia]

Hello.

I am a member of a trade union.
This union consists of a number of suppliers.
These suppliers are divided intoo three groups: strategic suppliers, preferred suppliers, listed suppliers.

Whan can listed suppliers mean?
I have no idea.

Thank you for your assistance.

 

[teechar]

These suppliers are divided into three groups: strategic suppliers, preferred suppliers, listed suppliers.

What can "listed suppliers" mean?

I am just guessing here, but I get the feeling that the category of "listed suppliers" is lower in the hierarchy than "preferred suppliers" which in turn is lower than "strategic suppliers."