---
title: PHP agent licenses
source: https://docs.newrelic.com/docs/licenses/product-or-service-licenses/new-relic-apm/php-agent-licenses
---

We love open-source software, and use the following in the New Relic PHP agent. Thank you, open-source community, for making these fine tools! Some of these are listed under multiple software licenses, and in that case we have listed the license we've chosen to use.

| **Library**                                                                          | **License**                                                                                                                       |
| ------------------------------------------------------------------------------------ | --------------------------------------------------------------------------------------------------------------------------------- |
| [BSD C library functions](http://www.freebsd.org)                                    | [BSD](http://www.freebsd.org/copyright/license.html)                                                                              |
| [C JSON parser](http://sourceforge.net/projects/cjson)                               | [cJSON MIT](http://sourceforge.net/projects/cjson)                                                                                |
| [C URL](http://curl.haxx.se)                                                         | [Curl MIT/X Derivative](http://curl.haxx.se/docs/copyright.html)                                                                  |
| [Compression Library](http://zlib.net)                                               | [Zlib](http://www.gzip.org/zlib/zlib_license.html)                                                                                |
| [Laravel Support from In-Touch Insight](http://www.intouchinsight.com/)              | [Apache 2 (BSD-style)](http://www.apache.org/licenses/LICENSE-2.0)                                                                |
| [MD5](http://openwall.info/wiki/people/solar/software/public-domain-source-code/md5) | [Public Domain](http://openwall.info/wiki/people/solar/software/public-domain-source-code/md5)                                    |
| [Perl Compatible Regular Expressions](http://www.pcre.org)                           | [PCRE (BSD-style)](http://www.pcre.org/licence.txt)                                                                               |
| [PHP](http://www.php.net)                                                            | [PHP (BSD-style)](http://www.php.net/license/)                                                                                    |
| [Secure Sockets Layer](http://openssl.org)                                           | [Open SSL License](http://www.openssl.org/source/license.html)                                                                    |
| [Symantec Root Certificates](http://www.symantec.com/page.jsp?id=roots)              | [Symantec Root Certificates](http://www.symantec.com/content/en/us/about/media/repository/root-certificate-license-agreement.pdf) |
| [Thread Safe Resource Manager](https://github.com/infusion/PHP/blob/master/TSRM)     | [TSRM (BSD-style)](https://github.com/infusion/PHP/blob/master/TSRM/LICENSE)                                                      |

The remainder of the code is covered by the [New Relic agent license agreement](https://docs.newrelic.com/docs/licenses/license-information/other-licenses/new-relic-agent-license).