It states a firm with two thousand has no rival (10)
I believe the answer is:
communique
'it states' is the definition.
'a firm with two thousand has no rival' is the wordplay.
'a firm' becomes 'co' (a firm is a company).
'with' says to put letters next to each other.
'two thousand' becomes 'mm'.
'has no rival' becomes 'unique' (something unique has no rival).
'co'+'mm'+'unique'='COMMUNIQUE'
(Other definitions for communique that I've seen before include "Official statement" , "Official announcement" , "Source of news" .)