借殼上市(Reverse Merger)是指未上市公司併購上市公司,避免經過正式IPO流程以達到上市目的。國內外實證文獻結果多顯示,借殼上市的公司平均而言規模較小、事前營運表現較差、財報品質不佳且股價表現波動度大,隱含借殼公司為股票市場帶來不穩定因素。本文認為應以整體社會福利的角度來評估借殼上市是否對市場造成危害:借殼提供未上市公司快速上市管道以獲得市場先機,然其亦可能成為差公司內線交易管道。因此,本文將市場先機大小與股票市場流動性納入考量,建立五期模型試以預測不同借殼規範下所帶來之社會福利。結果指出在適當參數範圍下,將借殼股移至市場流動性較小的子市場做交易將達到社會福利極大化,此乃因為其可有效限制差公司進入市場內線交易的誘因,而有實質營運的公司仍可透過借殼管道上市以搶得市場先機。
This thesis establishes a theoretical model to investigate welfare issues related to reverse mergers, which are a type of mergers used by private firms to become publicly traded without resorting to the initial public offering (IPO) process. It proposes that reverse mergers provide a way for private firms to get listed rapidly and gain first-mover advantages in the product markets, but the managers of poor-quality firms may use reverse mergers to get listed and exploit uninformed investors through insider trading. This thesis finds that moving the reverse merger stocks to a stock market with lower market liquidity may be the best choice in terms of social welfare. This arrangement effectively limits the insider trading gains of the poor-quality firms’ managers, thus depresses their incentive to undertake reverse mergers. At the same time, it still allows firms that have good market opportunities but cannot satisfy the IPO standard to get listed through reverse mergers.