Factual error: Tom Keen watches an arms deal. The supposedly German plates of the BMW read "DD17-36F9." This, however, is not a possible combination in Germany, as there would not be numbers in the first half, nor a letter after a number in the second part. [exceptions from the first being the most important officials' cars like the federal president's, but even then the latter applies]. Furthermore, no more than 4 numbers can be used, except for in police and military vehicles (which also never have a letter after a number, and start "Y" for military, or "DD-Q" for Dresden police). "DD-F1736" would have been a correct plate for the town of Dresden, for example. (00:23:15)
Factual error: The snakes in the King of England's pit are all constrictors. They do not have venom and are too small to see a human as prey, yet they show a man dying from a bite by one of these snakes.
Phoebe vs Max: The Sequel - S3-E1
Factual error: All the orange juice that sends Max flying through the air couldn't possibly be strong enough to do so. We already know that Max is pretty strong (The Girl with the Dragon Snafu).
Purpose in the Machine - S3-E2
Factual error: When examining the sand, Bobbi states "According to carbon dating..." Fitz finishes by saying "It's a billion years older than the earth." However, carbon dating is only good at determining the age of something to about 60,000 years old. The only thing carbon dating could tell about the sand is that it is 60,000 years old or older. It certainly couldn't determine that the sand was 5 billion years old.
Factual error: When asked about a trial Sebastian Berger replies that there was a jury verdict on a trial that took place in Germany. Germany has no jury based court system.