14 HARVARD LAW REVIEW, it in the hands of future assignees.^ They must be covenants touching the use of the land itself, and not merely the products of it,2 nor the conduct of the owner of it, and if they are to be enforced by assignees of the covenantor they must be made for the benefit of other land which he retains, and afterwards con- veys, or in pursuance of a general plan relating to the land to which they relate. ^ The doctrine, therefore, if it were applied to personal property, would not be unlimited in its scope, nor be applicable except under certain circumstances and conditions. It is not necessary now to consider the general question whether it would not be inconsistent with the freedom of sale of personal property to permit restrictions to be placed upon the use of it in the hands of purchasers. It is no doubt true that there are many conditions which cannot be imposed by owners of personal property upon the use that is to be made of it here- after. The question now relates to the effect of a contract made by the owner of a patent right with respect to the use of an article which he has the exclusive right to make, use, and sell. The contract is made as one of the conditions upon which he parts with this exclusive right, and is made for the benefit of the rights under the patent which he retains, and which it may be he after- wards conveys to others. It is a contract made, it may be, in pursuance of a general plan for the distribution of his rights over the whole territory embraced in his patent rights, and for the benefit of all who may purchase from him any parts of those territorial rights. In all these points the conditions are analo- gous to those under which the law of restrictive covenants with respect to land is applied, and the question is only whether under these circumstances the same principles are applicable to the sale of patented articles for use in certain territories, and whether by means of notice brought home to the purchasers the conditions so imposed may be enforced. With regard, to real estate it is well settled that, if land be sold subject to a restrictive covenant taken for the protection of other 1 Keates v. Lyon, L. R. 4 Ch. App. 218; Master v. Hansard, L. R. 4 Ch. D. 718 ; Renals v. Cowlishaw, L. R. 9 Ch. D. 125; L. R. 11 Ch. D. 586; Nottingham Patent Brick & Tile Co. v. Butler, L. R. 15 Q. B. D. 264. 2 Brewer v. Marshall, 19 N. J. Eq. 537. « Spicer v. Martin, 14 App, Cas. 12 ; MacKenzie v, Childers, L. R. 43 Ch. D. 265; Parker v. Nightingale, 6 Allen, 341 ; Dana v. Wentworth, ill Mass. 291 j De Gray v. Monmouth Beach Club House Co., 50 N. J. Eq. 329.
