As defined by Fraud.net:
“Email tumbling is a way of filtering incoming emails using variations of a specific email address. For tumbling an email, users only have to insert a “+” or “.” into the pre-section of their email before adding other text. While this might be helpful to consumers in some regards, it could allow vehement abuse from fraudsters also.”
In general, Socure, White Pages Pro, and ID Analytic’s email scores all take potential email tumbling into account. The use of one or more of these data services should be sufficient to guard against tumbling.
If you want to fire specific tags for possible email tumbling, you can use regex to check for "+" in an email address.
What is regex?
A regular expression, aka regex, is a sequence of characters that specifies a search pattern in text. Usually, such patterns are used by string-searching algorithms to "find" or "find and replace" operations on strings, or for input validation.
Within a workflow, you can use regex to parse a string value from a user input or service request (assuming the service request produces a string).
The following example shows the tag “Email Tumbling Warning” set if the email address has a “+” character using regex.