§ 4.Cases of extra profit analogous to rent, are more frequent in the transactions of industry than is sometimes supposed. Take the case, for example, of a patent, or exclusive privilege for the use of a process by which cost of production is lessened. If the value of the product continues to be regulated by what it costs to those who are obliged to persist in the old process, the patentee will make an extra profit equal to the advantage which his process possesses over theirs. This extra profit is essentially similar to rent, and sometimes even assumes the form of it; the patentee allowing to other producers the use of his privilege, in consideration of an annual payment. So long as he, and those whom he associates in the privilege, do not produce enough to supply the whole market, so long the original cost of production, being the necessary condition of producing a part, will regulate the value of the whole; and the patentee will be enabled to keep up his rent to a full equivalent for the advantage which his process gives him. In the commencement indeed he will probably forego a part of this advantage for the sake of underselling others: the increased supply which he brings forward will lower the value, and make the trade a bad one for those who do not share in the privilege; many of whom therefore will gradually retire, or restrict their operations, or enter into arrangements with the patentee: as his supply increases theirs will diminish, the value meanwhile continuing slightly depressed. But if he stops short in his operations before the market is wholly supplied by the new process, things will again adjust themselves to what was the natural value before the invention was made, and the benefit of the improvement will accrue solely to the patentee.
The extra gains which any producer or dealer obtains through superior talents for business, or superior business arrangements, are very much of a similar kind. If all his competitors had the same advantages, and used them, the benefit would be transferred to their customers, through the diminished value of the article: he only retains it for himself
