Never-seen-before footage of JFK assassination shot by a Texas businessman emerges: What we know

A new video showing the moments after John F Kennedy was shot in 1963 has emerged and will go to auction later this month. In the footage, the president's motorcade could be seen speeding down a Dallas freeway toward a hospital. The footage was captured by Dale Carpenter Sr who reached Lemmon Avenue in Dallas hoping to film Kennedy and his motorcade.But when he reached, the motorcade already passed. Carpenter rushed to Stemmons Freeway and by the time, Kennedy was already shot. The footage remained a family heirloom. When Carpenter died in 1991, the reel passed to his wife and then to the daughter and finally to the grandson.

What we know about the footage
RR Auction where it will be put up for sale said it is the only known film of Kennedy's car on the freeway.
The footage shot by Abraham Zapruder, a bystander, was the one providing details of the assassination. This new footage shows what happened before and just after the Zapruder film was shot.
It is over a minute long and contains nothing that can change what we already know.
Only a handful of people outside Carpenter’s family have seen the footage so far.
Clint Hill, the Secret Service agent, who sprang from a car behind Kennedy's and then climbed onto the president's car, also saw the footage.
Carpenter's grandson, James Gates, said the film was not much talked about in the family though everyone knew about it.
Gates said he came into the possession of the film in 2009 or 2010 when his mother handed him a milk crate that had some 30 film reels including this one. When he first viewed the Kennedy footage, he was underwhelmed as it did not show Kennedy but he was struck by Hill's bravery.
Kennedy is not visible in the video as he was lying across the back seat with his head in his wife's lap