When Hunter and Danny try escaping. Hunter takes his watch off a bad guys wrist and puts it in his pocket. But when they move into the hallway, he is wearing his watch on the wrist of his gun hand.
Exterior hospital: Clive Owen is handed a coffee. Stratham sees Owen and backs his car towards him. At 42:58 the coffee is on Owen's dashboard. At 43:02 (just a few seconds later) it's gone. It's a weird goof because there was specific dialog and business about handing over the coffee. Then it just disappears. They probably cut out a shot of it spilling on Owen.
When Danny is tied to the chair and the fight begins, he jumps out a window. There is no sign of the chair nor any pieces of it.
When Danny is chased by the Jaguar, his car hits a Golf and the left tail light is smashed. Later when he drives away from the hospital after the fight, the tail is not broken.
When Danny first meets his agent in Oman he is standing on the right of the white Mercedes. They talk and after a short while Danny says "Ok Let's go" and immediately steps into the car from the left side.
When Hunter sits with Anne in the cafe in Paris the menu items written on the wall have prices in Euros, in 1980 it should have been Francs.
The case, which supposedly contained $6 million, was carried with ease. The largest US currency available is the $100 bill, which weighs 1 gram. Six million in 100s would weigh over 130 lbs.
The sequence featuring a car chase starting and finishing at the hospital featured many vehicles with license plates showing three numbers and four letters, a format which has never been used in England.
The briefcase in the movie is too small to carry six million dollars, which would require ~2.5 cubic feet of space. The briefcase shown is not filled, and probably only has about one cubic foot of volume.
All the cars in the UK scenes bore numberplates consisting of 3 numbers followed by 4 Letters, - this is not the format for any region of the uk. Though N Ireland does employ 3 letters then 4 numbers. But as these plates were illegal, then offences were committed during filming on public roads.
In some of the stunts Danny performs while he is tied to a chair there is no seat part and front legs of the chair, there is only the back portion of the chair.
About 15 minutes, Danny attempts to rescue Hunter. When Danny first sees him, Hunter's beard is long and unkempt. 5 minutes later, his beard has been trimmed much shorter.
After Danny was playing boxing with Davies some where in Paris, France, they went to an office , on the glass door of the office the word "Manager" was written in Arabic. Which is the word "modeer" but it was written in Arabic letters
At around 17:00 when Danny is on the airplane, there is rain on the window. At 30,000 feet, the plane would be above the clouds and, therefore, there would be no rain.
Mobile radio sets with short antennas are used, which came into use much later.
The type of helmet used during the assassination of the last target is of a later era.
The movie takes place in 1980, but one of the very first establishing shots in the movie shows a red Pontiac Fiero, which didn't come out until 1984.
At one point there is a shot of the Eiffel Tower, featuring the lighthouse. This was added for the 21st century celebration but the movie takes place in the early 80s.
In the escape scene early in the movie, De Niro's character Hunter takes a Glock 17 handgun from a guard. This weapon was not manufactured/sold until about 1984. Since the scene is set in 1980 it is somewhat improbable that he would have one.
When Spikes leaves the van where Davies' dead body lies, the intersection on background is crossed by semi-trailer pulled by series 4 Scania truck. Scania introduced 4-series trucks in 1995.
In two of the London aerial shots, three Mercedes Citaro low-floor articulated buses can be seen - which only started production in 1997, and were introduced to London in 2002. Moreover, there were no articulated buses in London at all in 1980, when the movie is set.
At 59 minutes, when the helicopter lands on the banks of the River Thames in London, a sign warning of sharks is visible on the quay side.
When the sabotaged truck is leaving the depot just prior to the 'Boston Brakes' job, it is next to a rail yard. One of the locomotives has the insignia of Vic rail/v-line meaning it was shot in Victoria - the south eastern state of the Australian mainland.
The sequence featuring a car chase starting and finishing at the hospital featured many vehicles with license plates showing three numbers and four letters, a format which has never been used in the United Kingdom.
In the opening scene when the guy stands at the window in Mexico, there's a word written on the wall which is in Arabic.