82 Shackleford v. Kiser Co., 131 Ala. 224, 31 So. 77. See also Clanton Bank the rule is not universally followed. There are decisions upholding an assignment of all future book debts of a business,83 and assignments for value of rights under contracts not yet made, but expected to be made, have been upheld by some courts in the United States.84 In any event it would seem that every court would admit that authority given to an assignee to collect a claim arising under a future contract is valid until revoked either in fact or by operation of law, as by the death of the assignor. The effect of an assignment of such claims now seems in most jurisdictions analogous to that produced by an assignment of a present claim under the law existing prior to the protection by courts of equity of such assignments. It is to be observed that the limit generally set by policy to the effectiveness of an assignment of a chose in v. Robinson, 195 Ala. 194, 70 So. 270; Cor v. Hughes, 10 Cal. App. 553, 102 . Pac. 956; Green v. Consolidated Wagon, etc., Co., 30 Ida. 369, 164 Pac. 1016; Stromberg v. Bill, 170 111. App. 323; Richards v. Inter-Ocean Newspaper Co., 181 111. App. 515; AEtns Trust A Bar. Co. v. Nackenhorst (Ind.), 122 N. E. 421; Famaworth v. Jackson,
32 Me. 419; Lightbody v. Smith, 125 Mass. 51; Herbert v. Bronson, 125 Man. 475; Eagan v. Luby, 133 Mass. 543; Taylor v. Barton-Child Co., 223 Mass. 126, 117 N. E. 43; Raulins v. Levi, 232 Maw. 42, 121 N. E. 500; Neumann v. Mining Co., 57 Mich. 97,
33 N. W. 000; Heller v. Lutz, 254 Mo. 704, 164 S. W. 123, L. R. A. 1915 B. 191; Bell v. Mulholland, 90 Mo. App. 612; Thompson p. Gimbel, 71 N. Y. Misc. 128, 128 N. Y. S. 210; Rodijkeit v. Andrews, 74 Oh. St. 104, 77 N. E. 747, 5 L. R. A. (N. 8.) 564; Lehigh Railroad Co. v. Woodring, 116 Pa. 513, 9 Atl. 58; Porte v. Chicago Ac. R. Co., 162 Wis. 446, 166 N. W. 469. An assignment after the contract has been made or the employment has begun made by an attorney in fact whose authority was given him prior to the existence of the contract or employment is equally invalid. Ellis v. Saline
County Coal Co., 199 111. App. 219. In O'Niel v. William B. L. Kerr Co., 124 Wis. 234,102 N. W. 573 (s. c. sub nom. O'Niel v. Helmke et al., 70 L. R.A. 338), it was held that an assignment of the proceeds of milk thereafter to be sold to a person to whom the assignor regularly sold milk, but with whom he had no contract was ineffectual. Compare cases in preceding note upholding assignments of future earnings by one having an existing employment but no executory contract.
83 Tailby v. Official Receiver, 13 App. Cas. 623; Preston Nat. Bank v. George T. Smith Co., 84 Mich. 364, 47 N. W. 502. See also Bisaell v. Hill, 10 Mo. App. 593. Since the Judiciary Act an assignment of a future chose in action still is operative only as an equitable assignment, but an assignment of existing rights is given the name at least of a legal assignment. Hambleton v. Brown,  2 K. B. 93. See further, infra, Sec. 446.
84Edwards v. Peterson, 80 Me. 367, 14 Atl. 936, 6 Am. St. Rep. 207; Close v. Independent Gravel Co., 156 Mo. App. 411, 138 S. W. 81. See also Kendall v. United States, 7 Wall. 113, 19 L. Ed. 85; Metcalf v. Kinoaid, 87 Ia. 443, 54 N. W. 867.
A present assignment of a future debt must be distinguished from a contract to assign in the future or to pay out of a fund to be collected. In a transaction of the latter sort further action by the assignor is contemplated. The precise words used by the parties are not important, except as aiding an inquiry whether the transaction between assignor and assignee was understood to be complete, and to require no further action by the assignor.
The question whether an attempted assignment in any form of future earnings even under an existing employment is invalidated by the bankruptcy of the assignor as to wages earned subsequent to the assignment has been somewhat disputed. It is generally true that property transferred as security without fraud or illegal preference may be enforced by the creditor of a bankrupt even though the personal liability of the debtor is discharged .86 On the other hand, a debt founded upon a contract, express or implied, is provable in bankruptcy and not enforceable against a discharged bankrupt thereafter.87
As has been seen the assignment of future earnings cannot be regarded as an immediate transfer of any property, but the assignee has an authority or power to collect, and an implied agreement on the assignor's part not to revoke this power. Furthermore, unless the equity of the situation shall induce the court to change its ordinary principles the assignor's right to wages when they have been earned will be regarded as vested in the assignee so far as a right in the chose in action can be transferred. It seems impossible to find anything here which can be called a provable claim, and a discharge in bankruptcy is only applicable to provable claims. Even the implied contract not to revoke the authority of the assignee does not seem such a contract right as is provable in bankruptcy. Accordingly no valid technical reason can be found for denying the right of the assignee to earnings after bankruptcy.88 But the hardship of the case has induced many courts to hold the assignment invalid as to such earnings.89
85 See 19 Harv. L. Rev. 667.
86 Shaw v. Silloway, 146 Mobs. 503, 503, 14 N. E. 783. See also U.S. Bankruptcy Act, Sec. 87 d.
87 U. S. Bankruptcy Act, Sec. 63 a
Corporate mortgages frequently assign in terms future earnings. Such a mortgage involves an attempted assignment of future choses in action as well as tangible property, and is generally held not good against creditors until the mortgagee takes possession.90
It has been said by the Supreme Court of the United States: "We apprehend that the doctrine has never been held, that a claim of no fixed amount, nor time, or mode of payment; a claim which has never received the assent of the person against whom it is asserted, and which remains to be settled by negotiations or suit at law, can be so assigned as to give the assignor an equitable right to prevent the original parties from compromising or adjusting the claim on any terms that may suit them."91 but if these words can be regarded as including a contract right, the accuracy of the statement is open to question. There seems no doubt that so long as a claim is sufficiently defined by an assignment so that it can be identified,
88 The assignee was protected in Mallin v. Wenham, 209 111 262, 70 N. E. 564, 65 L. R. A. 602, 101 Am. St. Rep. 233; Monarch Discount Co. v. Chesapeake & Ohio Ry. Co., 285 111. 233, 120 N. E. 743; Citizens' Loan Assoc, v. Boston & Maine Railroad, 196 Mass. 628, 82 N. E. 696, 14 L. R. A. (N. S.) 102S, 124 Am. St. 584, 13 Am. Caa.365. See also Raulins v. Levi, 232 Mass. 42, 121 N. E. 500.
90Re West, 128 Fed. 205; Re Home Discount Company, 147 Fed. 538; Re Kama, 148 Fed. 143; Re Line-berry, 183 Fed. 338; Levin. Loevenhart, 138 Ky. 133, 127 S. W. 748,30 L. R. A. (N. S.) 376, 137 Am. St. Rep. 377; Leitch v. Northern Pac Ry. Co., 95 Minn. 35, 103 N. W. 704.
90 Galveston Railroad v Cowdrey, 11 Wall. 459, 20 L. Ed. 199; Gilman v. Illinois 4 M. Tel. Co., 91 U. S. 603, 23 L. Ed. 405; American Bridge Co. v. Heidelbach, 94 U. S. 798, 24 L. Ed. 144; Sage v. Memphis, etc., R. Co., 125 U. S. 361, 8 S. Ct. 887, 31 L. Ed. 694; United States Trust Co. v. Wabash Western Ry. Co., 160 U. S. 287, 307, 14 S. Ct. 86, 37 L. Ed. 1085; Mississippi Valley, etc., Ry. Co. v. United States Ex. Co., 81 111. 534; Ellis v. Boston, etc., R. Co., 107 Mas. 1; DeGraff v. Thompson, 24 Minn. 452; New York Security Co. v. Saratoga Gas Co., 159 N. Y. 137, 63 N. E. 758, 45 L. R. A. 132.
91 Kendall v. United States, 7 Wall. 113, 116, 19 L. Ed. 85.
and it arises out of an existing contract the assignment is none the less valid because the amount payable is subject to contingency or dispute;92 and if the assignment is valid it should be protected against destruction by the action of the assignor and the debtor.93 Limitations have sometimes been set by statute to the right to assign future salary or wages,94 and these statutes have been held a valid exercise of the police power.95