[BritTim]

Originally Posted by ferrety

Thanks Tim appreciated would you be willing to give me the sieve script for it?

Usually, the best way of figuring out the sieve code for something that can be done using a Rule is to

• Create the Rule
• Go to Edit custom sieve code (see bottom right of the page)
• Find the sieve code associated with the Rule you just created.
• Copy the code.
• Cancel to exit from Custom Sieve and delete the Rule you created temporarily.

Doing this for your problem, you get

if 
  allof(
  address :is ["To","Cc","Resent-To","X-Delivered-To"] "MyAlias@MyDomain.com",
  header :matches "X-Mailer" "MailChimp Mailer*"
  )
{
  discard;
  stop;
}