During the June-July period, we received a lot of requests from publishers to be able to more effectively track the direct and indirect traffic generated by feedly readers. To address that request, we added then a utm_source decoration to the title of the article – the link which leads users from feedly to the publisher’s site.
Today someone reported that adding the utm_source was interfering with information already encoded in the URL. At first we did not understand what they meant. After doing some research, it seems that the titles of some RSS feeds link directly to third party sites (and not the publishers’ sites) and in that case, utm_source is valuable information to be sent to that third party.
Even though this seems to happen for less than 0.0001% of all the articles we serve, it seems to be a valuable use case so we pushed out a new version of feedly which instead of replacing utm_source=feedly simply adds utm_reader=feedly.
This is going to impact negatively the publishers who are using utm_source to track their engagement in feedly but hopefully they can change their analytics to look for utm_reader instead of utm_source.
Also to be clear: feedly never touches any of the links that publishers embed in the content of their posts because those links often link to third party sites and some have affiliate or other type of sponsorships associated with them.
Update: The change has been rolled out to both the main channel and the beta channel.