COPPA, or the Child Online Privacy and Protection Act of 1998, is a law in the United States requiring websites which can potentially collect information from minors under the age of 13 to have written parental consent or some other method of legal guardian acknowledgment, allowing the collection of personally identifiable information from a minor under the age of 13. If you are unsure if this applies to you as someone trying to register or to the website you are trying to register on, contact legal counsel for assistance.