Market abuse is a concept that encompasses unlawful behaviour in the financial markets and for the purposes of this regulation it should be understood to consist of insider dealing unlawful disclosure of inside information and market manipulation. The eu market abuse regulation eu mar came into effect on 3 july 2016 and was onshored into uk law on 31 december 2020 by the european union withdrawal act 2018 changes to eu mar were made by the market abuse exit regulations 2019 to make sure that the onshored legislation uk mar operates effectively in the uk. The market abuse regulation is a comprehensive legislative document that helps to protect . Market abuse regulation mar market abuse regulation mar author financial stability financial services and capital markets union regulation eu 596 2014 entry into force 02 july 2014 articles requiring implementing measures article 22 designation of competent authorities