Both trump.org and trump.tv have been purchased by an anonymous buyer, amid speculation that the GOP presidential nominee may launch his own television network if his White House bid doesn't pan out.
"He wasn't even organized enough to purchase this domain (or www.trump.tv) at public auction, and he wants to run the U.S.A.?" the message says.
The owner of the page writes that he was contacted by Trump's attorneys for violating a trademark infringement, adding: "Guess who still owns the domain ... not that guy!"
Last week, The Financial Times reported that Trump's son-in-law had met with investors about possibly starting a TV network.
And before last week's final presidential debate, Trump launched a live Facebook broadcast for those "tired of biased, mainstream media reporting" in what many saw as a test run for the hypothetical network.