From Action Comics #11 (April 1939). Written by Jerry Siegel; drawn by Joe Shuster.
Superman fights probably his most despicable opponents yet: stock brokers who are selling shares of what they think is a dry oil field. I’m pretty sure that stocks don’t work the way they’re described in this story, but suspending disbelief, these guys are unrepentantly heinous.
Superman gets back at them by buying up all the bad stock, then personally drilling for oil on the property until he finds it. He then sells back the stock to the crooks for an enormous sum and destroys the well.