In many cases, buyers are not informed about their valuations and rely on experts, who are informed but biased for overbidding. We study auction design when selling to such “advised buyers.” We show that a canonical dynamic auction, the English auction, has a natural equilibrium that outperforms standard static auctions in expected revenues and allocative efficiency. The ability to communicate as the auction proceeds allows for more informative communication and gives advisors the ability to persuade buyers into overbidding. The same outcome is the unique equilibrium of the English auction when bidders can commit to contracts with their advisors.

We analyze how proxy advisors, which sell voting recommendations to shareholders, affect corporate decision‐making. If the quality of the advisor's information is low, there is overreliance on its recommendations and insufficient private information production. In contrast, if the advisor's information is precise, it may be underused because the advisor rations its recommendations to maximize profits. Overall, the advisor's presence leads to more informative voting only if its information is sufficiently precise. We evaluate several proposals on regulating proxy advisors and show that some suggested policies, such as reducing proxy advisors' market power or decreasing litigation pressure, can have negative effects.