We may retain personal information necessary to: (a) protect our business, systems, and users from fraudulent activity, (b) to address technical issues that impair existing functionality, (c) necessary for us, or others, to exercise their free speech or other rights, (d) comply with law enforcement requests pursuant to lawful process, (e) for scientific or historical research, (f) for our own internal purposes reasonably related to your relationship with us, or to comply with legal obligations.