Issue #169 in acm latex: How to remove the copyright box?
The answer to this question appeared in issue #169 and it received good feedback, so I am reposting it here as well.
To remove copyright box, just add nonacm=true, authorversion=true:
% \documentclass[sigconf, authorversion=true, nonacm=true]{acmart}
nonacm: Use the class typeseting options for a non-ACM document, which will not include the conference/journal header and footers or permission statements.
authorversion: Whether to generate a special version for the authors’ personal use or posting