COPPA, the Children's Online Privacy Protection Act, is a US law that legislates how website operators may gather personal information from children under the age of 13. The complexity of the paperwork involved with collecting such information is the main reason why many US-based online communities do not allow people under 13 to become members.
See also[]
- Children's Online Privacy Protection Act on Wikipedia
- Why does FANDOM have an age limit? (topic) on Community Central
“COPPA is a US law that fandom has to follow, which regulates how companies handle the personal info/data of children. However, most companies don't want to deal with the overhead of getting parental contest and keeping it on record and etc, so instead they just make their site only 13+ (or etc) instead. Sites such as Google and etc also do this as well.”