Yahoo News published a copy of the letter, which was addressed to CNBC's Washington Bureau Chief Michael Cuddy. In it, the two aspiring Republican nominees say the want the debate to be only two hours instead of three, and they'd like the chance to make opening and closing statements.
"Mr. Trump and Dr. Carson do not, and will not, agree to appear at a debate that is more than 120 minutes long including commercial breaks," the letter states. "Further, the debate must include opening and closing statements from all the candidates."
Trump and Carson - who were recently parodied by Jimmy Fallon and David Alan Grier - are the current Republican frontrunners in the polls. (At this point in the 2012 election cycle, pizza baron Herman Cain held the top spot.) Many credit Trump's appearance with boosting the ratings of the first two GOP debates. The second one was dinged by viewers for lasting three hours instead of two. Huh, maybe because there are too many candidates? At least Scott Walker saw the writing on the wall and did us the favor of bowing out.
Do you think CNBC will make those changes? And if not, what are the chances Trump and Carson will actually keep their word and skip it?
WATCH: Is Donald Trump changing his campaign strategy?