中文摘要：

新股保荐代表人的频繁离职引起市场各方对保荐代表人是否尽责履职的担忧。本文以2004-2012年1186家IPO公司的保荐代表人为样本，分析并检验保荐代表人离职的主要原因及其对保荐制度效率的影响。结果发现：（1）保荐代表人离职与IPO市场活跃程度及券商承销排名显著相关，而与IPO公司质量或公司风险等因素无关；（2）离职保荐代表人更可能去排名更低的券商，且保荐代表人离职前后承接的IPO项目质量没有显著差异；（3）进一步分析发现，保荐代表人离职没有对IPO公司募集资金项目变更行为产生显著影响。研究表明，经验丰富的保荐代表人资源稀缺是其离职的主要原因，而规避风险或逃避处罚则不是；同时，并没有发现保荐代表人离职影响保荐制度效率的证据。本文从保荐代表人角度拓展了承销商声誉的现有文献，也在保荐代表人作用定位及监管策略方面为箭在弦上的注册制改革提供了重要参考。

英文摘要：

Using a comprehensive sponsor representatives （SRs） sample of 1 186 Chinese IPOs from 2004 to 2012, this paper investigates the causes and consequences of SRs＇ resignation decision. First, we find that the SRs＇ resignation decision is significantly associated with the IPO market activity and the rank of sponsor institutions （Sis） underwrite IPOs. Second, the resigned SRs are more likely to go to the low-rank Sis and there are no significant differ- ences in the quality of IPOs they sponsored between before and after they resigned. Third, we further analyze and find no evidence that SRs＇ resignation has a significant effect on the firms＇ decision of changing fund purpose. Overall, our results suggest that the explanation of the scarcity of SRs with more experienced is the main cause of SRs resignation. Meanwhile, SRs＇ resignation does not impair the efficiency of the sponsorship system.