The Academy Awards (search) have some new rules, including a ban on ads by studios trashing the competition.

In a decree released Thursday, the Academy of Motion Picture Arts and Sciences (search) formally banned studios from referencing rivals in ads aimed at voters.

The new rule "prohibits specific and disparaging references to other pictures or individuals competing in a given category in ads, mailings, Web sites or other forms of campaign communication," according to the Academy.

It's an apparent response to DreamWorks' trade-newspaper ad last season that promoted best supporting actress contender Shoreh Aghdashloo (search) from "House of Sand and Fog" in a way that was perceived as a slap at fellow nominee Renee Zellweger (search) from "Cold Mountain."

The ad included clips from newspaper and TV critics saying that Aghdashloo deserved to win the Oscar, but that Zellweger was more likely to get it. The Motion Picture Academy denounced it as an "attack ad." DreamWorks apologized and later bought a special ad congratulating Zellweger on her victory.

Another new rule: some Oscar voters outside of Los Angeles and New York have complained that they have trouble seeing all the movies necessary for an informed ballot — so the Academy of Motion Picture Arts and Sciences has authorized studios to send free coupons to them.

The issue was part of last season's debate over whether studios should discontinue sending voters "screeners," which are free tapes and DVDs of current movies.