With GDPR in effect shortly, this is becoming critical. Illumina has enabled the use of Beta munchkin. When we test using marketo_opt_out=true, the cookie mkto_opt_out being set but associated with the subdomain the page is on rather than with the top/root domain. However, _mko_trk is properly being set to the top domain so this isn't something fundamentally wrong with the domain level. The problem with this is if the cookie is dropped on a www.illumina.com page - only www.illumina.com pages stop being tracked. The Marketo landing pages at mkt.illumina.com are still tracked. The same issue happens the other way as well - if the query parameter is added to an mkt.illumina.com page, then we'll stop tracking those pages but not the www.illumina.com pages. There are numerous other subdomains associated with Illumina as well so really need the cookie to be associated with illumina.com so that pages across all the subdomains stop being tracked.
Here are a few example pages to try:
When examining the cookies, you'll see that _mkto_trk is associated with .illlumina.com but mkto_opt_out ends up associated with the subdomain of either www.illumina.com or mkt.illumina.com depending on which page you used. Conversly, you have to set marketo_opt_out=false on each of the subdomain pages in order to have it removed from each subdomain it is on.
Is anyone else experiencing this problem with the Marketo Opt Out functionality? I have submitted this to Support but I thought I would ask on the community for any insights as well.