Task Reassignment Reporting

@peterh I don't think there is a way to capture the 'Reassign' event associated with a Task. This may be possible provided if you provide the Reassign feature of yours where you will be doing it from a Task Report or a button in the same Task which will submit the task, do the necessary save operations and finally reassign.

@peterh, as said by @sikhivahans, there is no direct way to capture the "Reassign" event.
But, I have an alternate workaround. Events like "Reassignment", "Active", "Assigned" or "Cancelled" of a task can be tracked in the process history.
1.) To check if the task was reassigned more than once:
You will need to filter the process history for Task Events, and again filter based on task Id. Check for "Reassigned" events. Then you can tell if the task was reassigned more than once.
2.) Reassigned by a user not in the original assignee group:
From the process history, you can find the event when the task was first "assigned", and find the associated task assignees - these will be the original assignees. Then you can compare those with the current assignees of the task(assuming the task is in Active state currently).

The solution I am suggesting will however need you to create a custom plugin - which may take a considerable time to create.

@chetany Good catch mate. Unfortunately, I have missed the audit trail part that will be taken care of by the process history.

I think this could be doable provided if we parse the 'Process History' using the 'Process History' plugin at http://bit.ly/2cFnsPt and it might be easier(for instance, assignee information returned by Process History isn't a direct user or group objects) to create a new plugin which does all these by accepting a set of inputs. And as opined by @chetan, it takes a considerable investment of time.

@sikhivahans, yes Process History plugin can be reused, may need some modification.

@chetany It actually needs parsing the desired information from the plugin's output.

@chetany well said. Worth reading this post. Thank you.

Thanks all. If reporting is required, sounds like the Process History plugin is the way to go. We are moving towards a customized reassignment model so we shouldn't need this in the future.