Google is making some changes to help reduce spam.

It is adding new requirements for bulk senders, defined as those who send more than 5,000 messages to Gmail addresses in a day.

They will have to authenticate their addresses, stay below a spam rate threshold, offer a one-click unsubscribe button in their emails, and process the unsubscribe request within two days.

The changes go into effect in February.

Google announced Yahoo will implement the same changes.