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PHP-Plagiarism-Checker v1.3 — Copyleaks detects online plagiarism and checks content distribution. Use Copyleaks to find out if textual content is original and where it has been used before. This example in PHP shows how to integrate with the Copyleaks cloud to search for copyright infringement.
Similar copyright

Some additional repos to consider:
laravel-yearly — :copyright: :package: Laravel 5 Package that keeps your copyright up to date. Guys, it's a serious issue, no jokes!!!
Privacy-for-Buttons — Privacy for Buttons helps you to protect your visitor's privacy providing full-featured social media buttons without third-party tracking. It is free software and released under the BSD license See <http://www.opensource.org/licenses/bsd-license.php> for more details WARNING: this application is able to fetch original background images from the social media providers. You may only do this at your own risk and responsibility! Depending on your country, this might infringe copyright laws. If you're unsure,better create your own! NOTE: This application is still in a very early state and under heavy development. It is not meant for productive use yet.
Yiippod — Flash and HTML5 video player without any logos or copyright on screen. Based on free version of Uppod player
phpMumbleAdmin — Copyright (C) 2010 - 2013 Dadon David. PMA@ipnoz.net
phpmathpublisher — phpmathpublisher from http://www.xm1math.net/phpmathpublisher/ PhpMathPublisher - Copyright 2005 Pascal Brachet - France
zf2-languages — Open plugin for using multilanguage on ZF2 applications Copyright (C) 2015 SREd
BingHomepageAPI — This API helps you to gets the current Bing Homepage details including the Image URL and Image Copyright Information and use it.

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