[ https://issues.redhat.com/browse/DROOLS-5668?page=com.atlassian.jira.plug... ] Sylvain Lemoine edited comment on DROOLS-5668 at 9/24/20 4:28 PM: ------------------------------------------------------------------ ok thanks you for considering this issue as deserialization of kieSession from previous drools version is pretty critical for our project. Anyway, I push a bit further my investigations and simply letting pass accumulate node as I did was obviously wrong  due to the way tuple for  dormant activation are now fully serialized (A), and it takes part in the definition of the activationkey in dormantActivations. As (A) is not present in earliest 7.x serialized session, the following piece of code is not able to filter dormant activation: {code:java} RuleImpl rule = activation.getRule(); ActivationKey activationKey = PersisterHelper.hasNodeMemory( rtn ) ? PersisterHelper.createActivationKey( rule.getPackageName(), rule.getName(), activation.getTuple().toObjects(true)) : PersisterHelper.createActivationKey( rule.getPackageName(), rule.getName(), activation.getTuple() ); this.tuplesCache.put( activationKey, activation.getTuple() ); return !dormantActivations.contains(activationKey);{code}   was (Author: slem1): I push a bit further my investigations, seems due to the way tuple for  dormant activation are now fully serialized (A), and it takes part in the definition of the activationkey in dormantActivations. As (A) is not present in earliest 7.x serialized session, the following piece of code is not able to filter dormant activation: {code:java} RuleImpl rule = activation.getRule(); ActivationKey activationKey = PersisterHelper.hasNodeMemory( rtn ) ? PersisterHelper.createActivationKey( rule.getPackageName(), rule.getName(), activation.getTuple().toObjects(true)) : PersisterHelper.createActivationKey( rule.getPackageName(), rule.getName(), activation.getTuple() ); this.tuplesCache.put( activationKey, activation.getTuple() ); return !dormantActivations.contains(activationKey);{code}   -- This message was sent by Atlassian Jira (v7.13.8#713008)