Dist. Ct. did not err in dismissing for lack of venue in plaintiff’s claim under Clayton Act, alleging that defendant improperly interfered with competitive bidding process on device used by emergency vehicles to override traffic lights at intersection so as to allow them to go through intersection safely. Record showed that: (1) none of alleged illegal activity occurred in Southern Illinois District; (2) none of intersections in Southern Illinois District had specific equipment at issue in lawsuit; and (3) defendants’ presence in judicial district was limited to six direct sales to buyers, or .002% of defendants’ overall sales. Ct. found that defendants’ presence in judicial district was too de minimus to satisfy “transacting business” element for establishing venue under section 12 of Clayton Act. It further concluded that section 12’s venue and nationwide service provisions must be read together. Fact that defendants had conceded personal jurisdiction with respect to Illinois as whole did not preclude it from contesting venue in Southern Illinois District.