Try member of a smart list (your list) and member of Possible Duplicates...

Hi Mark - I tried doing this but there is filter for finding duplicates.  Am I doing something wrong?

Hi Darren, 
If dupes are a concern of yours, try this out: http://www.ringlead.com/integration/marketo-integration/.
RingLead is being used by 100+ Marketo customers to prevent and remove duplicate records in both Salesforce and Marketo.

The filter you would use is "member of a smart list" name would be possible duplicates.

No real easy way to tell and you should also not just trust the duplicate leads tab either
b

Deduping Marketo if All Marketo Prospects are NOT in Salesforce

NOTE: If two duplicates are in Marketo and only one is in Salesforce, the steps below will merge the two duplicates in Marketo.
 

1. Login to Marketo and Create a New List as RingLead Dedupe List (NOT a Smart List)

2. Create a New Campaign

   1. Smart List “Added to List”. Set List Name to RingLead Dedupe List

   2. Flow is RingLead Webhook

3. Go to Lead Database > Possible Duplicates > Leads

4. Click “Select All”

5. Go to Lead Actions > Marketing > Add to List

6. Select the List created in step 1

I have RingLead in Marketo but have been having problems with it.

Also, one key point that's missing from the above steps to merge dupes in Marketo is that you need to use the "Added to List" trigger, not filter, since webhooks cannot process in batch. I missed that the first time and this didn't work, so I just had a bunch of failures in the campaign. And, of course, you need to active the Smart Campaign before you add your possible dupes to the RingLead list.

That said, I ran through this process again - it's still running now - but I'm seeing mostly failures:




Suggestions? 

I've had other problems with RingLead in Marketo, too (working with their support to try to resolve). 

Despite the errors I was seeing earlier, it looks like sending my Marketo dupes through RingLead did work since Possible Duplicates now shows just 43 leads (down from 22k+ I had earlier), so I'm running those through the flow again now.