I have found an instrument variable ( $Z$ ) for my econometric model. The relevance constraint holds, however I still have a question about the instrument exogeneity and that is: It is said that it needs to be convincingly ruled out any direct effect of the instrument on the dependent variable or any effect running through omitted variables. But what if $Z$ influences another variable, $V,$ by which $Y$ is influenced ( $Z\to V\to Y$ )? Is then my exclusion restriction violated? I have data on $V,$ such that I could control for it.

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