The Supreme Court recently approved an amendment to Federal Rule of Appellate Procedure 29 (amicus briefs), which will go into effect December 1, 2010, unless Congress legislates otherwise.
The amendment has a familiar ring, as a substantially similar requirement is already in Supreme Court Rule 37.6. Under new FRAP 29(c), amicus briefs must contain a statement indicating whether "a party's counsel authored the brief in whole or in part," "a party or a party's counsel contributed money that was intended to fund preparing or submitting the brief," and "a person—other than the amicus curiae, its members, or its counsel—contributed money that was intended to fund preparing or submitting the brief and, if so, identifies each such person." As noted in the related Judicial Conference Report, the new rule "serves to deter counsel from using an amicus brief to circumvent page limits" on the party briefs.
This and other FRAP amendments (incorporated into a clean copy of the amended provisions), along with letters from the Chief Justice transmitting them to Congress, are here.