Describing themselves as the "world's foremost innovator of high-tech, high-performance communications and security technology", they specialize in everything from mobile technology, home computing, digital image processing, to home computing and security and take great pride in that they have become the leading corporation in all the fields it has entered, dominating over all competition. They stand adamant to change the way people think about and perceive Information Security Architecture (ISA). In order to transition people and win them over to the implementation of their ctOS system city-wide, they provide free Wi-Fi Hotspots throughout the city.
 Notable Personel
- Charlotte Gardner - Vice-president of Public Relations and intermittent Mayor of Chicago following the death of Donovan Rushmore.
- Raymond Kenney / T-Bone Grady - Ex-employee of Blume, created the base code for ctOS.
- Tobias Frewer - Ex-employee of Blume, pioneer of implementing the ctOS system throughout the city of Chicago.
- In German, the world "Blume" (without a silent 'e') translate to "Flower" which could possibly be the inspiration behind the corporations logo.
- Charlotte Gardner is currently the highest ranking personel from the Blume corporation seen in the game, leaving many of the true power players in the City, such as the CEO, as unknowns.