1)   SourceGuardian PHP Encoder 7.0
SourceGuardian is the only serious choice for protecting and encrypting your PHP source code assets. With flexibility that other products only dream of Professional developers everywhere are using SourceGuardian products to distribute their scripts.

 2)   phpSHIELD PHP Encoder 3.0
phpSHIELD protects your PHP Source Code with a powerful, easy to use encoder, which creates a native bytecode version of the script and then encrypts it.

 3)   PHTML Encoder 5.0
The PHTML Encoder allows encoding PHP scripts before distributing them. The script code is encrypted before saving. You can lock your scripts to predefined machine via machine ID. It is possible to combine protected/unprotected scripts in one site.