Is it all that different from indexing for search? That does not seem to require a license from the copyright holder under U.S. law (but other countries may tre

Is it all that different from indexing for search? That does not seem to require a license from the copyright holder under U.S. law (but other countries may treat as a separate exploitation right). If indexing for search is acceptable, then something that is intended to be more transformative should be legal as well. (Personally, I think that even indexing for search should require permission from the copyright holder.)