SysML 1.5 specifications have been officially published by the OMG.
The specifications are available to download from www.omg.org/spec/SysML/1.5. According to the Object Management Group, the primary change from SysML v1.4 is the introduction of an Abstract Requirement that can be extended to support other kinds of requirements such as property-based requirements.
It is also important to know that SysML has been published by the International Organization for Standardization (ISO) as a full International Standard (IS) under the title "ISO/IEC 19514:2017, Information technology -- Object management group systems modeling language (OMG SysML®)".
