Hi @user934814,
Thank you for reaching out to the Community and providing your feedback! Constant Contact has different packages in which different features are available. To turn off the branding within an inline or pop-up sign up form, you need to have the Email Plus package. You can find out more information regarding which features are available in each package here!
https://knowledgebase.constantcontact.com/articles/KnowledgeBase/7030-difference-between-plans?lang=en_US
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