As it would appear, Siri and iCloud are viewed as potentially problematic security risks at IBM. So much so, that the company blocks the use of Siri and iCloud from all of the iPhones of their staff. The reason? Siri queries send information over to Apple’s servers and IBM sees this as unsecure due to the ignorance of what happens with the data as it is processed on Apple's end. Additionally, iCloud stores the employees’ information on publicly available servers, which is also viewed as unsafe by IBM.
This means if you work for IBM, then you will not be able to spread your personal information across several devices and not be able to ask Siri for the closest restaurant. The spokesperson and company CIO (chief information officer), Jeanette Horan, had this to say:
Originally Posted by Jeanette Horan
While the move is understandable, since many people can publicly use the iCloud servers, it would probably be a good idea if Apple started offering a corporate version of their iCloud service with different servers that could be dedicated to different companies. This would have a heavier sense of security since the servers would be separate from that of the servers used for the public and the dedicated servers would ensure safety from conflicts with other companies' data. In turn, Apple could generate some revenue from offering the services.
Sources: MIT via 9to5Mac