The film was animated in the French studio Mac Guff in Paris, and although a US production, it was written and directed by Spaniards and Frenchmen, making Despicable Me (2010) a very cross-cultural production.
The name of the main protagonist, Gru, appears to be taken from the Russian Military Intelligence agency GRU. GRU is an acronym for Glavnoye Razvedyvatel'noye Upravleniye (roughly translates to Main Intelligent Department/Directorate), the foreign military intelligence directorate of the Russian Armed Forces. It is the largest Russian intelligence agency, six times larger than the SVR (formerly the KGB). This may hint at Gru's own origins.
The girls undercharge Vector when they deliver his cookies. Based on the clipboard Margo is holding when they pay him the initial visit, the prices of each of the box of cookies is thus: Coconutties $6, Choco Swirlies $6, Minty Mints $6. Vector ordered 4 Minty Mints, 15 Coconutties, 2 Toffee Totes and 2 Caramel Clumps. The Minty Mints and Coconutties alone would cost $114, plus the cost of the Toffee Totes and Caramel Clumps, means that the girls charge of only $52 was way below what it should have been.
One of the pictures hanging on the walls of Gru's home (it can be seen when the three girls first enter the house, next to the front door to the left) is a "Wanted" poster for the capture of Jesse James, a notorious Wild West gunman and bandit.
The trivia items below may give away important plot points.
While Gru is floating in space while orbiting the moon, we see that the number on Gru's "Swan Lake" ticket is 072069 - July 20, 1969 is the date of first moon landing, which Gru is seen watching in flashbacks.
After the girls' bedroom has transformed into a more comforting place, the camera angle allows the audience to see some famous paintings that Gru has stolen. 'Leonardo Da Vinci''s "Mona Lisa" hangs on the wall, and Vincent van Gogh's "Starry Night" can be seen leaning up against the wall on the floor.
May 26, the day around which the entire film revolves - it's the day of the girls' dance recital, the capture of the moon, and the big chase to rescue the girls from Vector which leads to Gru and the girls becoming a family - is the birthday of Steve Carell's daughter, Annie. Elisabeth Anne Carell, who was Steve and wife Nancy's first child, was born Saturday, May 26, 2001. He said in 2008: "When Elisabeth Anne was born six years ago, something inside me just snapped and my perspective on what was important changed overnight."