Bombproof your list imports with proxy fields


List imports are scary stuff.

There are a lot of things that can go wrong with pushing a file of leads into your database. Duplicates. Overwritten values. Bad data. List imports open you up to a lot of risk to your Marketo database all at once.

But you can set up a line of defense for your more sensitive fields using what I call “proxy fields”, which help you intelligently manage how data is overwritten.

List imports are a daily task for us, and so we’ve gotten pretty strict on the data requirements for new leads, particularly with the lead status field. When we upload, we need to be able to distinguish between suspects/inquiries and truly qualified leads.

We block field updates for the lead status field, meaning it only accepts the first value from a list import, and won’t be changed by future imports. This helps us ensure a lead that’s already an MQL cannot move backwards and become a suspect from a later list import.

List imports with field blocking

Here’s my crappy drawing of how field update blocking works. New leads get a status, existing leads (who already have a status) are unchanged.

This is handy, but field blocking is a double edged sword. Suppose a lead was originally imported as a suspect, but is now on an import list where we’ve marked them as an MQL. In that case, we actually want them to become an MQL, but since that field blocking is in place, that lead’s status won’t be changed, and we’d be forced to fix it manually.

To work around this, we created a proxy field, called “Import Lead Status.” It replaces the standard lead status field on our import lists, and more intelligently manages the data, making sure leads can move forward in status, but not backwards.

Marketo List imports with proxy fields

Here’s what imports look like with a proxy field. We’re now conditionally assigning lead status from list imports, so existing leads can be updated when it makes sense. Sweet!

Here’s how to set it up in about 10 minutes:

  • Create a new text field with a name distinct from the original field (this should be a marketo-only field), such as “Import Lead Status.” Ensure no field updates are blocked. You may also want to set a few list import aliases for this field, as this is the field you’ll want all your list imports to map to in the future.
  • Create a smart campaign set to run every time a lead qualifies, with two triggers: one for anytime your new field’s value changes, and another for when the lead is created (since data value change triggers won’t fire for new leads). You’ll also want to include two filters:
    • A filter to exclude any lead statuses you do not want to change. You need to include this so your import lead status doesn’t move any leads backwards inadvertently. I decided that anything Marketing Qualified or beyond (SAL, SQL, etc) shouldn’t be changed.
    • A filter the specifies that the import lead status field isn’t empty (for the aforementioned “lead is created” trigger)
  • For your new Smart Campaign’s flow, you just need one step, “Change Data Value” that sets the lead status by grabbing the value from the proxy field, using a field token.

How to set up proxy fields in MarketoHow to set up proxy fields in Marketo


The nice thing about this process is it’s invisible to your other Marketousers. We have a standard import template that we require for any list uploads, and I have “lead status” and variations of it mapped to this proxy field as a safeguard, so to anyone importing lists, this is no different to how they managed the process before. Since implementing this process, it’s had a big impact on efficiency and accuracy for us.

Obviously this is just one example of a proxy field – you could do something similar for geographic fields, company names, phone numbers, and much more. If you’re doing something similar, I’d love to hear about it!