In the boardroom scene at the end, when Linus is standing in front of the window, Harborside Terminal in Jersey City is visible. Once he leaves the room, this very large building disappears from the background.
Near the beginning of the film, when Linus is explaining his plastic to David, he holds a lighter to the piece of plastic and brags that it cannot scorch. However, as he turns the plastic over, a giant black spot is visible where the plastic was scorched. In the next shot, the spot on presumably the same piece of plastic has disappeared.
In the cooking school sequence where snow is seen falling outside and accumulating on the window, the filmed scenes of Paris in the background clearly show no snowfall or snow on the streets at all.
When the students take the soufflés out of the oven, the soufflé of the Asian lady is very high. In the next shot, when the soufflés are being inspected, hers is well below the rim of the dish.
(At about 14:00) While Sabrina is writing her suicide note to Father, we see her hand from two perspectives. From the side, we see Sabrina writing with two fingers on the pen (first and second fingers). From above we see only one finger on the pen (first finger).
After Sabrina tells Fairchild that the moon is reaching for her, we see a shot of the moon through the trees at the Larrabee party. Directly above and to the right of the moon, you can see the strings and holes of that backdrop.
Linus starts talking to his secretary via the intercom on his desk, but he does so before actually completing the push of the switch on the intercom.
It is unrealistic that David would not recognize Sabrina after Paris, as she did not look very different after her transformation, especially in her face and figure.
When David confronts Linus regarding the gossip column, he slaps the newspaper down; however, no sound is heard until a second afterward.
When Linus Larrabee has just boarded the Maude Larrabee tugboat, he crosses the front deck, and we can see the shadow of a member of the crew at the very end of the shot.
Sabrina slips her suicide note under her father's door. Even though she doesn't go through with the suicide, the note he would undoubtedly find should have to be dealt with.
In the French cooking school the master chef demonstrates an exaggerated wrist motion necessary for cracking an egg, but when he cracks the egg his wrist is stiff and his arm moves from the shoulder. He makes this mistake twice.
When David confronts Linus in his office, Linus dismisses his secretary by calling her "Miss McCartney". Her character name is actually Miss McCardle.
Elizabeth pronounces Mercedes as Merce-Deez.