Guidelines for law enforcement authorities seeking information about Twitter accounts - https://help.twitter.com/en/rules-and-policies/twitter-law-enforcement-support
Official submission form to submit a legal request to Twitter - https://legalrequests.twitter.com/forms/landing_disclaimer
Twitter Transparency Report - Information and statistics on content removal requests submitted to Twitter - https://transparency.twitter.com/en/reports/removal-requests.html
Content Policy - https://www.redditinc.com/policies/content-policy (See Rule 3, Rule 4 and Rule 5)
Adult Content Policy - https://tumblr.zendesk.com/hc/en-us/articles/231885248-Adult-Content
Remove non-consensual explicit or intimate personal images from Google - https://support.google.com/websearch/answer/6302812
How to remove a page from the Bing Index - https://www.bing.com/webmasters/help/how-can-i-remove-a-url-or-page-from-the-bing-index-37c07477