A government effort to break up Facebook Inc. from Instagram and WhatsApp would defy established law, cost billions of dollars and harm consumers, according to a paper company lawyers have prepared in the wake of rising antitrust legal threats.
The 14-page document, reviewed by The Wall Street Journal, offers a preview of the social-media giant’s defense as federal antitrust enforcers and members of Congress continue to pursue investigations into Facebook’s power and past competitive behavior. Probes of other technology companies…
