Including the (free) Advanced Custom Fields plugin inside a free / premium theme is allowed.
You can include your (premium) purchased add-ons within a premium theme as long as it is made clear in the copyright / information that the add-ons are NOT to be used or distributed outside of the premium theme.
You can not include (premium) purchased add-ons within a free theme.”
Welcome to the Advanced Custom Fields community forum.
Browse through ideas, snippets of code, questions and answers between fellow ACF users