single opt-in
noun[CorU]
E-COMMERCE,MARKETINGukusa way ofbuildingalistofclientswho areinterestedinyourproductsorservicesby onlyincludingpeoplewhoaskto havetheirnameaddedto theemaillist:
E-mailssenttosingleopt-inlistsare oftencategorizedaslightversionsofspam.
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double opt-in