Hi guys.
Warning: noob here. I apologize if some of my questions seem stupid.
The background: I "own" several very targeted email lists but I don't know what is the best way to monetize them if any. For example, I have an 80k unique emails list of women who have signed/applied to a Fitness Gym. I've, manually build this list by downloading it from Analytics in Excel (I know it sounds weird, but one of my client's thank-you pages appends the email), extracted only the emails from the "thank you" URL and removed all duplicates.
I did not build the lists in the classic opt-in way. I have access to these lists and they are genuine (not fake or bought)
Roughly, I know that the emails can be used for:
1. Remarketing/Retargeting (including FB lookalikes) - I will use this in the future.
2. Sell them - Unlikely. Selling them will make them useless in a very short period of time.
3. Rev Share - Don't know how this can be done to be ok with both parties. I'm not paranoid but I'm not naive either.
4. "Classic" email marketing - I would like to know how I can do this in my situation. Since I did not acquire them, personally, I have a hard time using them with emailers (SPAM issues)
5. Unknown method? - Is there anything that can be done with email lists, other than the above methods?
Thanks, and I look forward to your help 
Sell the list as a LLA to FB mediabuyers. Don't provide the data but inject it in their FB account via Team Viewer.
This way you keep the database clean and you keep it to yourself, without breaking a law.
Not sure how many potentials you will find but oke... Option 2 and 3 will give you good money, but are tricky.
You can definitely use them for classic e-mail marketing. To avoid spamming you would have to clean them out thoroughly. Spamming is no issue.
Hmm, didn't think about it from that angle. In that case, I would say Revshare is your best bet. 