On the subject of founder-managed companies and a performance comparison, I have only found the following certificate.
It includes family-run companies, but only from Europe.
The three largest positions are: $COLO B (+2,17 %) , $EZJ (+0,82 %) and $BC8 (-0,25 %)
The performance clearly lags behind that of the Eurostoxx50! But I don't think that is representative enough.
But whether it is really an advantage that a company is run by its founder depends, I think, above all on the founder's vision and his openness to change.
