The American Antitrust Institute submitted comments on February 1, 2021 on the U.S. Federal Trade Commission’s (FTC) proposed changes to the Hart Scott Rodino (HSR) reporting requirements. AAI supports some of the proposed changes that will make needed updates to HSR reporting to keep pace with new business models and practices. As AAI explains in its comments, however, it opposes the proposed rulemaking’s provision that would exempt from reporting many partial ownership acquisitions, including many involving private equity and institutional investors. The proposal comes at a time when increased—not decreased—scrutiny of partial ownership transactions is needed. AAI has been at the forefront of the push to recognize and understand the competitive harm that can flow from partial ownership transactions and has repeatedly urged competition authorities in various sectors to pay more, not less, attention to these transactions. AAI’s comments explain why the exceptions to the reporting exemption in the proposed rule are not enough to address these concerns, as they leave it up to companies themselves to decide who is and is not a competitor in an approach akin to the “fox guarding the henhouse.” AAI concludes that the proposed reporting exemption does not serve the interests of competition and consumers, particularly in light of concerns over rising concentration in the economy and many critical sectors.