"Let us prey" was considered the unofficial motto of John D. Rockefeller. Rockefeller became a giant in the oil industry. His company, Standard Oil Company, controlled most of the oil industry. He did this by "preying" on smaller oil companies. His business tactics forced these smaller oil companies either to sell to Rockefeller or to go out of business. This gave Rockefeller and his company nearly total control over the oil industry. As a result, his profits soared. Other business leaders realized this was a way to make a lot of money. As a result, they began to follow Rockefeller's lead and use the same business practices in their industry. Andrew Carnegie is a good example of this within the steel industry. JP Morgan did the same in the banking industry. While this tactic could be viewed as ruthless, it certainly was profitable.