I have multiple work spaces but each workspace has a different number of anonymous leads. Has anyone seen this? or know how these anonymous leads are put into Marketo?
In case of workspaces, it is likely that workspace specific munchkin (Marketo tracking) code has been generated, one for each workspace. Some of you web pages contains the code for one workspace, some other pages the codes for another workspace, etc...
So the very first time a visitor arrives on your site, if that person has no Marketo cookie, the workspace the resulting anonymous lead is created depends on which munchkin code is created.
See here for more details : Add Munchkin Tracking Code to Your Website - Marketo Docs - Product Docs
Here's the documentation over it Understanding Anonymous and Known Leads
If a previous Marketo known lead clears his/her cache I'm assuming their Marekto cookie will be cleared (not sure). If this is the case, it seems like the the stats for anonymous will be impacted (i.e, previously known leads will not be classified as annonymous. Is that true? What additional insight can you share. Thank you.
If you clear your browser cookies (not the temporary file cache -- these are usually different options) then the Munchkin cookie is removed from the browser.
Marketo is not notified that the cookie has been deleted, since this action occurs completely on the client side (you can delete cookies without even being connected to the internet).
On the next page view, Munchkin will see there's no cookie and will create a new, random cookie. As you noted, that cookie will be associated with a new anonymous lead until some action is taken to associate the cookie with a known lead (form fillout, email click).
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