Habe dies noch nie gebraucht, kann also nicht sagen, welche 'Nebenwirkungen' damit verbunden sind, aber es gibt doch die From Property "Anonymous Form"...
Aus der Hilfe:
If a form is assigned the "Anonymous form" property, its documents do not contain an $UpdatedBy field; instead, the documents contain an $Anonymous field with a value of "1."
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If you want a document's author or editors to remain anonymous, define a form that doesn't record the names of people who create or edit it. For complete anonymity, be sure that the author name does not appear elsewhere on the document -- for example, in a visible computed field.
On the Form Info tab, select "Anonymous Form."