When Larry and Dan are talking in Larry's office you can clearly see the bed sheet in the bed behind Dan. When Larry walks to the bed it has no sheet and he pulls one out of the roll.
The direction that Dan is facing after Larry calls him back into the office changes without Dan moving.
In the opening scene when Alice is walking down the street, the front of her hair is dyed a very bright red but in the next scene when she in the hospital waiting room with Dan, there are only a few streaks.
When Anna photographs a weeping Alice, she's using a 35mm Leica camera. However, at the gallery exhibition , the picture of Anna is a full frame, medium format print complete with black borders. Therefore, it was shot with a much less unwieldy instrument.
When Dan is cybersexing with Larry he types "I want to suck you senseless" in the typing area of the chatbox but when it appears in the box for Larry to read it says "I want 2 suck u senseless".
When Dan and Anna are at the opera (the English National Opera in London), the soundtrack is playing a recording of Wolfgang Amadeus Mozart's "Cosi Fan Tutte" in the original Italian. All productions at the ENO are always sung in English.
When Alice goes through US Immigration returning to New York, an American flag is improperly displayed on the wall with the stars in the upper right corner. The stars field should always be in the upper left corner of the flag.
Brazilian composer and rock singer Cazuza, Agenor de Miranda Araújo Neto's name is misspelled in the credits as Araugo.
Anna takes photos of Alice with a Leica M-series 35 ,, film camera in ambient light in her studio, hand-held, and from the sounds at a relatively high shutter speed that would be required to avoid motion blur. This would require high-speed black-and-white film. Latter the print of one of those photos is quite sharp, but also shows no grain, which, given the enlargement ratio, would be unavoidable.
Larry, when smoking, never exhales his cigarette smoke. Either he didn't actually smoke or the editing was badly done. When Dan smokes, the smoke is visible in his mouth, but he also never exhales.
When Dan hits Alice, his hand clearly does not connect with her face.
When Larry and Anna are having lunch to sign the divorce papers, the camera is bumped and image tilts for one frame at 1:13:43.
During Anna and Larry's big fight, Anna walks across the apartment to the couch and the sound of her footsteps are out of sync.
Reflection of camera and cabling during US immigration scene.
The camera is reflected in the ring when Larry and Anna are having dinner and the ring is put on the table.
Gaffer tape actor marks on the white rug when Dan is in Larry's office.
When Alice and Dan sit on the 109 bus, the destination is for Westminster Station. However, the bus travels east along Victoria Embankment past Blackfriars - the opposite direction to Westminster.
At 0:05:46, Dan jokingly introduces Alice to London trademarks such as policemen, telling her to "observe the distinctive helmet". But the helmets the police wear, with tapered helmet plate, are clearly not those of the Metropolitan Police Service and are more likely memorabilia from a police force outside of London.
The opening action has Dan taking Alice to the hospital, staying with her in the waiting room, and the two leaving together. Unless a patient is unconscious, hospital intake always involves an interview procedure where the patient has to give their name, insurance information, and relevant medical history. To call a patient out of the waiting room, the hospital staff uses the name on the intake records, rather than shouting "hey you" to the next person to be seen. Yet, when Dan and Alice are getting ready to part ways after the bus trip away from the hospital, he says, "I don't even know your name."