1459
To prevent observed abuse of the review system by developers or other third-party agents , Valve modified the review system in September 2016 to discount review scores for a game from users that activated the product through a product key rather than directly purchased by the Steam Store , though their reviews remain visible .
 organization: Valve
Please list all entity words in the text that fit the category.Output format is "type1: word1; type2: word2". 
Option: location, person, organization 
Text: {0} 
Answer:
 organization: Valve