you are right, these are not true indie games when they have a major publisher backing them. +Mikko Ahlroth
if Valve were publishing indie games that are available on Steam somehow then you would be correct, but because Steam itself is simply a delivery service here (meaning the developers are not tied down to Steam or Valve) nor do they have to give money to Steam for non-Steam purchases (like +Steven Demanett
said) games simply being available on Steam does not make them non-indie. But games that have publishers (which they are tied to no matter where they go and where they sell) are not indie anymore. Many Valve games (Counter Strike, Portal, Left 4 Dead) started out as indie games, but then were not called indie because they were published and or hired by Valve.