The Rules of Acquisition: Revised for the Modern Ferengi
The Ferengi Rules of Acquisition: Revised for the Modern Ferengi was a series of 285 aphorisms, guidelines, and principles that were created by Grand Nagus Zek in 2371 as a replacement for the Rules of Acquisition.

When Quark and Rom first learned about Zek's plan to write a new set of Rules of Acquisition, they were initially excited at the prospect of being the first Ferengi to learn from Zek's wisdom. However, when the book was finished and presented to them, they were horrified to discover that the new Rules of Acquisition promoted kindness and charity over money and profit. 

In attempting to look for a code in the revised rules, Rom read to his brother, Quark, the first word of each rule, reading: “If… never… keep… profit… a… good… smile… honesty.” While it could have meant something altruistic, the Ferengi took it to obviously mean nothing. Further attempts to decipher it included holding the book up to the light, smelling it, and tasting it. Their efforts proved fruitless, although Quark was still pondering the first word code to himself later on. 

It was later discovered that Zek had used the Bajoran Orb of Wisdom to talk to the Prophets, wishing to know the future. The Prophets found Zek to be excessively greedy and "de-evolved" him into a state which they equated to be an earlier, less selfish Ferengi – it was under this influence which Zek had decided to rewrite the Rules. After Quark became aware of this, he persuaded the Prophets to return Zek to normal, due to him informing them that "de-evolving" him would encourage contact with other Ferengi (which they wanted to avoid). To avoid scandal, the rules were never released to the public. ()

Background information
With the exception of Rule 23, the revised rules read essentially as opposites of their originals. Rule 23 is the only rule not to have been established in its original form prior to the airing of  and was not established until Enterprises .

de:Die Erwerbsregeln: Eine Neufassung für den modernen Ferengi
fr:Règles de l'acquisition: révisées pour le Ferengi moderne
Literature
Ferenginar