 FreeBSD is released under a variety of open source licenses . The kernel code and most newly created code is released under the two @-@ clause BSD license which allows everyone to use and redistribute FreeBSD as they wish . This license was approved by Free Software Foundation and Open Source Initiative as a Free Software and Open Source license respectively . Free Software Foundation described this license as " a lax , permissive non @-@ copyleft free software license , compatible with the GNU GPL " . There are parts released under three- and four @-@ clause BSD licenses , as well as <unk> license . Some device drivers include a binary blob , such as the <unk> HAL of FreeBSD versions before 7 @.@ 2 . Some of the code contributed by other projects is licensed under GPL , <unk> , <unk> and ISC . All the code licensed under GPL and <unk> is clearly separated from the code under liberal licenses , to make it easy for users such as embedded device manufacturers to use only permissive free software licenses . <unk> aims to replace some GPL dependencies in the FreeBSD base system by replacing the GNU compiler collection with the BSD @-@ licensed <unk> / <unk> compiler . <unk> became self @-@ hosting on 16 April 2010 . 
