Tracking of merged leads

[Anonymous]

Hey 

Im wondering how I can get the "old" data from leads that are being merged?
Also I've seen that Marketo automatically enters a value in an empty field if its empty before the merge

• When merging a lead with an empty field with another who has a value for that field, the merged lead will have a value in that field.

 Is it posible to customize this? For example only change the value if the new value is higher than 1 or something? 

Thanks in advance 
-Ingi

[Anonymous]

The only way that I know that you could do this would be to export them. Merge them in Excel and import them into marketo to update the fields.