The current version of the OMG SysML specification is OMG SysML v. 1.4, which is available from the SysML Specifications page of this web or can be downloaded from the OMG web.

You can find a OMG SysML v. 1.4 minor revision change summary as part of the Answer to the SysML FAQ: What is new in OMG SysML 1.4?.