Corrected entry: In the machine gunning of the train carriage scene the weapon would not have been available to the soldiers in 1891. While an order by the British army is said to have been placed in late 1888 for 120 Maxim guns it first saw only limited use during the First Matabele War of 1893. It officially entered British Service only in 1896, seeing action during the First Boer War.
Corrected entry: When Sherlock and Watson go to Paris, you see a oversight with the Sacre Coeur being constructed. The movie is taking place in 1891, the building of the Sacre Coeur started in 1895.
Correction: This entry is wrong, construction did not start in 1895. Groundbreaking occurred in 1875, with the foundation stone being placed the same year, and the foundation was completed in 1884. In fact, historical photographs from 1891 that shows construction of the Sacre Coeur similar to what is seen in the movie.
Corrected entry: In the final confrontation between Holmes and Moriarty it is revealed that Holmes switched Moriarty's notebook with a copy. Moriarty opens the copy to find a small page by page cartoon referencing dialogue between the two characters during the same scene when the notebooks were switched. It is impossible for Sherlock to have drawn the cartoon between the moment that Moriarty says the line and the moment when the notebooks are switched.
Correction: Sherlock is a deductive genius who wins fights by predicting exactly what his opponent is going to do next, even subtly guiding them to do it. It wouldn't have taken much effort at all for him to have directed the conversation to more or less match the cartoon he'd drawn ahead of time.
Correction: Holmes knows that Moriarty is a fan of Schubert, having heard him listening to one of his songs when meeting him at the college. He probably drew the cartoon afterwards based on that knowledge to rub salt in the wound, even if he didn't know that Moriarty would specifically reference The Trout when they encountered each other.
Corrected entry: The film starts in 1891. The first fight scene, in an alleyway, the cops walk by and one thug warns the other by yelling "Peelers". A "Peeler" was slang for a police officer, derived from the name of Sir Robert Peel, who developed the Metropolitan Police Act in 1928.
Correction: Robert Peel established the Metropolitan Police Force in 1829. By 1928 he'd already been dead for over 70 years.
Corrected entry: Irene Adler died of a type of tuberculosis that was so lethal that she coughed up blood and died within minutes. Moriarty picks up the blood stained handkerchief and later gives it to Sherlock who is seen sniffing it sentimentally. This lethal variant doesn't seem to affect either of them.
Correction: The only way we learn it is tuberculosis is Moriarty telling Sherlock. I think Moriarty poisoned Irene Adler - the disease is just the cover story which Sherlock (and was intended to) sees through.
Corrected entry: When Holmes is envisaging himself being pushed over the edge by Moriarty his left boot is correct, but just as he falls off of the ledge he is wearing a black and white trainer (sneaker). (01:51:10)
Correction: The right boot is polished and catches the light as Holmes' body moves over the railing giving it a bright appearance for a moment, but he is wearing a matching black boot on his right foot.
Correction: The implication is that these men were not British soldiers but agents of Moriarty.