Great question, Felix! Do these pdf change depending on criteria or is it just one file? If you want to automate it: For the first one, you may want to create different campaigns and attach the corresponding PDF to the email step it should be sent out from. Then you can use conditional formulas in Clay to filter out leads so they only get added to the right campaign column if they meet conditions.Otherwise, I would just attach the PDF to the one email in Smartlead so it's sent out anyways.