Is Proprietary Trading Detrimental to Retail Investors?
研究全能银行同时开展自营交易和零售银行业务时的利益冲突，发现银行会向零售客户出售自营组合中的股票，这些股票随后表现不佳，导致散户投资者回报降低。
ABSTRACT We study the conflict of interest that arises when a universal bank conducts proprietary trading alongside its retail banking services. Our data set contains the stock holdings of every German bank and those of their corresponding retail clients. We investigate (i) whether banks sell stocks from their proprietary portfolios to their retail customers, (ii) whether those stocks subsequently underperform, and (iii) whether retail customers of banks engaging in proprietary trading earn lower portfolio returns than their peers. We present affirmative evidence for all three questions and conclude that proprietary trading can, in fact, be detrimental to retail investors.