The bad List-Id's look like this:
List-Id: <capone-1-0> List-Id: <spc-230221-2> Previous discussion of my custom rule can be found here: <http://spamassassin.1065346.n5.nabble.com/Malformed-List-Id-header-td150228.html>
You may recall I have a local rule that flags badly-formatted List-Id
headers as probable spam. It works quite well. However, I've seen a couple
false positives recently from my bank and credit card companies. The
Message-IDs make it clear that both are coming from SparkPost, which seems
to be a company that handles bulk email for enterprise. Of course, none of
these companies make it easy to alert the people responsible for such mail
that they're sending spammy messages. While the credit card email was just
marketing, the bank email was from their account activity alert system, and
that I very much want. In any case, if you use SparkPost, please let them
know that they're sending broken List-Id headers.
