regrators

In those occupations that involved buying and selling the necessities of life, such as those of the fishmongers and the bakers, the officers of the fraternity, like the town authorities, were engaged in a continual struggle with "regrators," "forestallers," and "engrossers," which were appellations as odious as they were common in the mediæval town.

An Introduction to the Industrial and Social History of England Edward Potts Cheyney 1904

The commercial law of the Middle Ages is full of provisions against engrossers, forestallers, and regrators, all of whom were engaged in artificially raising prices to the consumer by obtaining some sort of monopoly.

The Evolution of Modern Capitalism A Study of Machine Production 1899