The evidence we uncover suggests that the practice of profit and risk sharing among keiretsu firms reduces the firm level idiosyncratic risk. However, rather than eliminating firm-level risk, it is being transformed into market-level risk. Since market-level risk is priced, this actually destroys shareholders’ wealth. Additionally, the heightened correlation among keiretsu firms essentially diminishes the diversification efficacy of a portfolio of keiretsu firms. In summary, our results suggest that the practice of profit and risk sharing, which on the surface seems to be a blessing, may actually have a detrimental effect on the value of keiretsu firms.