so my smart campaign is tracking who fills out our form (we have standardised forms) on a specific landing pages. Every event registration form has an opt-in box. I just want to know how i can track who has opt'd in for certain events.
Well, as Sandy asked - do you use any program/marketing campaign specific UTM parameters for the registration LPs? FYR: UTMs are the parameters added to the webpage URL after the "?" e.g. https://www.exmaple.com/some-path?utm_campaign=2022-webinar-product-release&utm_source=mkto&utm_medi...
In the above URL there are three UTM parms: utm_campaign, utm_source, and utm_medium.
If your registration LP had UTMs, you can use UTM values in the smart list filter's constraint to filter people who filled out the form and had their Email Opt-in change.
If you don't use UTMs in the registration page (which is highly recommended to track the interactions) - you can track by filled out form filter with constraint on the respective webpage (Marketo LP) assuming that your forms are placed on the Marketo LPs only (if they are not, you would have to use referrer constraint instead of the webpage constraint) and though the form is standardized/global, LP isn't and is local to the program/marketing campaign you want to track.
Check out below snapshot, I think this should help you find people (both who already were existing in the DB and got their data value changed, and who were created from the form fill-out.) Also, please be aware of the fact that Marketo retains the Change Data Value activity for a period of 90 days past the activity date. However, form fill-outs are retained for a period of 25 months past the activity date.
AFAIK, this should help you get correct set of people, I'll post an update if I discover any edge case/filter config missing.
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