HowTo Forward the mail to many addresses using procmail

We just need to add more addresses to the action line:

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* ^Subject: This is urgent$ ! first@one.com second@two.net third@three.org

If you have a large list of recipients, you might prefer to store the addresses in an external file you can edit without mucking with your Procmail filters:

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* ^Subject: This is urgent$
! `cat addresses.txt`