However, note that this is the legacy founding rituals, for creating a new legacy item.
While it eventually becomes clear from context that least=6th though 10th, lesser=11th through 16th, greater=17th through 20th, as far as I can tell NOWHERE in the book is this explicitly spelled out. Not in the feat descriptions, not in the item descriptions, not in the sections on how legacies work. DMs with rules-lawyer players, beware.