After a vulnerability that allowed hackers to access the sensitive personal data of an estimated 145.5 million individuals, Equifax is now facing numerous class actions along with multiple regulatory actions and investigations. “The facts as we see them raise the question of how well and whether Equifax tested the mega-breach scenario,” Mintz Levin partner Cynthia Larose told the Cybersecurity Law Report. In this second installment of our two-part series on incident response lessons from Equifax’s fallout, we provide experts’ top ten tips on ensuring a plan is efficient and effective. We also address the roles and responsibilities of key incident response stakeholders. In part one, we looked at Equifax’s mistakes and heard from experts on essential components of incident response planning and how to bolster those plans. See also our three-part guide to developing and implementing a successful cyber incident response plan: “From Data Mapping to Evaluation” (Apr. 27, 2016); “Seven Key Components” (May 11, 2016); and “Does Your Plan Work?” (May 25, 2016).