I read the text as the Wealth award goes to a player (the builder of the contract), whereas the Prestige award is granted to the building (the controlling player of each).
Rules, page 9 wrote:
Usually the active player is the only player affected by a building’s effect. However, when an effect refers to specific buildings as gaining or losing something, the player or players controlling the noted buildings will reap the benefit or detriment of that effect.
See the Corporate HQ example right below that, which has the same issue you're asking about here.