# Readwise Authors - Readwise API (Highlights) ![rw-book-cover|256](https://readwise-assets.s3.amazonaws.com/static/images/article1.be68295a7e40.png) ## Highlights - Finally, we de-dupe highlights by `title`/`author`/`text`/`source_url`. So if you send a highlight with those 4 things the same (including nulls) then it will do nothing rather than create a "duplicate". You can also use this endpoint to easily update a previously created highlight if a `highlight_url` was set. Pass the same url with a new text and the highlight's text will be updated. ^406965517