I think I know the answer based on my research but wanted to double check. Marketing would like to send an email to our customers (that have email) regarding a fundraising event we are hosting. It will not be related to any product or service. Am I correct in stating that they need to provide an opt out and also be very clear in the subject line of the message so that it is not misleading?

Are there any other issues we need to address that I am missing? This isn't something we do often so I am a little dusty on this topic.

There are requirements for a commercial electronic mail message whose purpose is to promote a commercial product or service. It doesn't sound like you're in that area. But I would allow some type of opt-out so that you don't pester a customer who doesn't want these messages. If you have an opt-out list now, remove the messages for them.

If it could be an ad under these rules, you have to include an clear indication that this is an ad, your physical address and the opt-out.