Drools Rules changes after Version 2.2.6 are included in the Authoring Platform release notes (as VAL-#### ticket references) rather than listed separately here.
2020
Drools Rules Version 2.2.6 - 26 March 2020 - Release Notes
Drools Rules Version 2.2.5 - 8 January 2020 - Release Notes (International)
2019
Drools Rules Version 2.2.4 - 28 November 2019 - Release Notes (International)
Drools Rules Version 2.2.3 - 30 September 2019 - Release Notes (International)
Drools Rules Version 2.2.2 - 13 September 2019 - (Managed Service)
Drools Rules Version 2.1.0 was an internal release test build.
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