I once received an inquiry into my ownership of stocks, in a court case that involved the top brokerage firms who, back in the fractional parts of a $ (1/8, 3/8, 1/4, etc.) were accused of selling "blue chip" stocks among a secret cabal of brokers inside the houses, sales based solely on the "odd or even" number in the fraction of the "blue chip" on certain days on a circulated list. I didn't own any of the stocks. The court was seeking about 3/4 billion $ in damages and 1/2 billion $ in penalty. Not sure how that turned out. Perhaps why enforcement can be so difficult.