A gclid can end up associated with the wrong caller when two people share a promo number’s active attribution window.Applies to: Google Ads, Invoca reporting
Answer
A gclid can be associated with different callers if the number presented to one visitor is later presented to another, and the first visitor calls in while the second visitor’s session is still active — the first visitor ends up with the second visitor’s marketing data attribution, including the gclid. This can happen in a few ways:- One caller calls a number, then gives that same number to someone else, who calls later.
- Two people use a shared public computer: the first writes down the number to call later, the second uses the same computer and calls right away, and the first also calls later.
- The Invoca Tag defaults to a 30-day attribution window. If a returning visitor’s earlier session is still active, they may be presented with a new promotional number due to number rotation (which changes every 5 minutes by default). When they dial that new number, the original marketing data from their first visit persists.
- During this window, other callers — legitimate or fraudulent — directed to the same promotional number can end up sharing the same gclid the original visitor held for up to 30 days.