Until recent times the law sought to fix by somewhat technical rules the validity of contracts restraining the exercise of a trade or profession; especially the question whether a restrictive promise unlimited in time or unlimited in space was not necessarily invalid was disputed. It was settled in England before the middle of the 19th century,62 that the mere fact that a covenant was unlimited in time did not necessarily make it unreasonable and unlawful. The court was greatly influenced by the fact that: "The good-will of a trade is a subject of value and price. It may be sold, bequeathed, or become assets in the hands of the personal representative of a trader. And, if the restriction as to time is to be held to be illegal, if extended beyond the period of the party by himself carrying on the trade, the value of such good will, considered in those various points of view, is altogether destroyed." 53 And though at the present time the fact that a promise is unlimited as to time may be of great importance in determining that it is unreasonable, it is not conclusive of unreasonableness.54 The upholding of a promise is often made easier by construing it, though in terms unlimited in time, as meaning a reasonable time,55 or for the promisee's life or continuance in business.56
51 United States v. Addyston Pipe & Steel Co., 86 Fed. 271, 281, 29 C. C. A. 141, 150, affd. 175 U. S. 211, 44 L. Ed. 136, 205, S. Ct. 96.
52 Hitchcock v. Coker, 6 Adol. & EL 438.
53 Hitchcock v. Coker, 6 Adol. & El 438, 454, per Tindal, C. J.
54 Hall Mfg. Co. v. Western Steel & Iron Works, 227 Fed. 588> 142 C. C. A, 220, L. R. A. 1916 C. 620; Smith v. Webb, 176 Ala. 596, 58 So. 913, 40 L. R. A. (N. S.) 1191; Styles v. Lyon, 87 Conn. 23, 86 Atl. 564; Thayer v.
Younge, 86 Ind. 259; Arnold v. Kreut-ser, 67 la. 214, 25 N. W. 138; Bunill v. Daggett, 77 Me. 545, 1 Atl. 677; Dean v. Emerson, 102 Mass. 480; United Shoe Machinery Co. v. Kimball, 193 Mass. 351, 79 N. E. 790; Foes v. Roby, 195 Mass. 292, 81 N. E. 199, 10 L. R. A. (N. S.) 1200; Southworth v. Davidson, 106 Minn. 119, 118 N. W. 363,19 L. R. A. (N. S.) 769; Diamond Match Co. v. Roeber, 106 N. Y. 473, 13 N. E. 419, 60 Am. Rep. 464; McClurg's Appeal, 58 Pa. 51; Stewart v. Bedell, 79 Pa. 336; Henschketr. Moore, 257 Pa.