John D. Rockefeller used the horizontal expansion as a way of establishing his standard oil business by coming into agreement with railroads.
John used horizontal expansion to ensure that he had monopoly in the oil business. Horizontal expansion is a method where a business would increase its dealings in the same market or industry in order to raise market share for its products.
He bought over his competitors in the market, acquired pipelines and then he had negotiations with railroads for favorable shipping rates for his products.
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