In court documents released on Monday in the $US10 billion ($A14 billion) case, the BBC argued that Trump's subsequent re-election showed the alleged defamation did not harm his reputation.
Trump has accused the United Kingdom's publicly funded broadcaster of defaming him by splicing together parts of a January 6, 2021, speech to make it appear he directed supporters to storm the US Capitol.
The documentary was first broadcast in 2024, shortly before the presidential election Trump won.
It featured one section in which he urged supporters to march on the Capitol, followed by another, from nearly an hour later, where he said "fight like hell".
Trump's lawsuit, filed in Florida, alleges that the BBC defamed him and violated a Florida law prohibiting deceptive and unfair trade practices.
The BBC has apologised to Trump for the edit but argues that the lawsuit should be thrown out.
As Trump won the election after the documentary's release, he "cannot plausibly claim that the documentary harmed his reputation," the BBC's lawyers said in their court submissions.
The BBC argued Trump could not prove the 12-second clip in the hour-long documentary that he alleges is defamatory was intended to create a false impression.
"Indeed, nothing better reflects how President Trump's supporters understood his remarks than their own statements, and over 100 defendants charged with offences related to January 6 told the courts that they interpreted President Trump's remarks as a call to action," the BBC's submission said.
The broadcaster also argued there was no jurisdiction to sue it in Florida as the documentary was not available to viewers there and the lawsuit concerned "a dispute about UK entities' role in a documentary aimed at UK viewers".
A two-week trial is listed to take place in February 2027 if the BBC's motion to dismiss is not successful.
18°C