Please use the following links to download the specification.
OSGi Core Release 5 Specification
OSGi Core Release 5 Companion Code
OSGi Compendium Release 5 Specification
OSGi Compendium Release 5 Companion Code
OSGi Enterprise Release 5 Specification
OSGi Enterprise Release 5 Companion Code
OSGi/Minimum-1.2 Execution Environment
CDC-1.1/Foundation-1.1 Execution Environment