*When all the lines are nines, it means:
There appears a flight of dragons without a head (leader).
Good fortune.
When all the lines are nines, it means that the whole hexagram is motivated to change into the hexagram Kun, The receptive, whose character is devotion. The strength of the Creative (1) changes into the mildness of the Receptive (2). Strength is indicated by the group of dragons, mildness by the fact that no one is claiming leadership among them [their head (leader) is hidden]. There will be no conflicts, quarrels, nor fights, and all decisions are made unanimously. Thus, the virtue of equality and harmony brings good fortune. This means that mildness in action joined to strength of decision brings good fortune.
Among the sixty-four hexagrams there are two assertions applied to the Chien and Kun hexagrams only, since each of them may have either all nines or all sixes:

Use (of) the nines, (be) not used by the nines, means:
Avoid contact with any external influential changes.
Do not depend on others for help to avoid rejection and intimidation.
Do away with the subjective view of prejudice; and handle all matters objectively.
- Information supplied by James S. Lee.