( CNN ) -- It 's best not to monkey around with Donald Trump -- or maybe that 's a bad choice of words . The billionaire real estate mogul is suing millionaire comedian Bill Maher for $ 5 million . Why ? Because Maher said -- in jest , as comedians are wont to do -- that he would donate $ 5 million to a charity if Trump could prove he was n't the `` the spawn of his mother having sex with an orangutan . '' `` I 'm not saying it 's true , '' Maher told Jay Leno on `` The Tonight Show '' last month . `` I hope it 's not true , but unless he comes up with proof ... I 'm willing to offer $ 5 million to Donald Trump that he can donate to a charity of his choice -- Hair Club for Men ; The Institute for Incorrigible Douche-bag-ery . Whatever charity . '' Opinion : Hijacking the media -- Trump shows how easy it is . Maher picked the figure after Trump , long a skeptic of President Barack Obama 's citizenship , offered to give $ 5 million to the charity of Obama 's choice if the president publicly released his college transcripts in addition to his passport records ahead of last year 's elections . The White House never directly responded to the challenge . Trump says he provided Maher with a New York birth certificate that proved he did n't descend from an ape -- but Maher has n't paid up . Trump filed the lawsuit in Los Angeles on Monday . Included in the court documents are a January 8 letter to Maher , accepting the $ 5 million charity challenge the day after his appearance on Leno , and a copy of Trump 's birth certificate , which lists Fred Trump as his father -- not an orangutan . It 's a free-swinging smackdown by two men used to speaking their minds and not backing down . Maher , never afraid to ape the object of his pithy humor , was unrelenting on `` The Tonight Show '' in pushing the simian connection . `` The color of his hair ( pauses for laughs ) and the color of an orange orangutan is the only two things in nature of the same color , '' Maher said to another round of nervous chuckles from the audience . The comedian 's reaction to the lawsuit ? `` What ? ? Really ? Hahahahahahahahahahahahahahahahahahahahahahahahahaha , '' he tweeted . Perhaps , he is waiting for Trump to release his long-form birth certificate .
Bill Maher suggests Trump mom mated with an orangutan . The comedian offers $ 5 million for Trump to prove otherwise . Trump 's birth certificate shows Trump as his father . Trump sues asking Donald Trump 's to pay up .