When playing the Trading Post version of Splendor, are you required to have the 3 black bonuses power to get the 5 prestige points for having the 5 green bonuses and 1 noble tile power?
On this page on ultraboardgames.com they explain the rules for the different powers and how to get them.
Requirement: You must have 3 black bonuses.
Power: 1 prestige point for each of your coats of arms on the board.
Requirement: You must have 5 green bonuses and 1 noble tile.
Power: 5 prestige points.
For the 5 prestige points the only thing you need is the 5 green bonuses and 1 noble tile. For the prestige point for your coats of arms you only need to have the 3 black bonuses. The bonuses are independent from each other so you can get any of them at the time you have the requirements.