28 HARVARD LAW REVIEW magistrate's certificates of loss, and the like.^^ Experience of these conditions and of the legal questions involved in them has not been such as to commend them for commercial purposes. It must be for the ingenuity of business to find some better mode of protect- ing the buyer-holder, if such protection is needed. IV The authorities say that a special letter of credit, i. e., one ad- dressed to a particular addressee, is not assignable.^^ On the other hand the understanding and custom of business men to a certain extent is different. Questions usually discussed under the head of assignability of letters of credit arise where the addressee seeks to pledge the letter or to assign it as security; in cases of business changes, as where an addressee parti;ership is changed or incor- porated or a new corporation succeeds to the business and good will of an old one, or a merger or a consoHdation occurs; in cases of a sub-contract or a number of sub-contracts with the seller-ad- dressee; or further where a letter addressed to a particular addressee nevertheless expressly states that it is assignable, or contains an express power of designating those in whose favor it may be made available. How shall we treat these cases? Where one attempts to assign such a letter, it is clear that under the offer theory no one may accept the offer, and thereby make a contract with the issuer, except the addressee to whom alone the offer is made. On the guarantee theory, the guarantee runs only to the creditor named, and no secondary liability can be incurred to anyone else except by means of a new contract. This rule has been applied very strictly to cases of business changes.^^ On the theory of contract for benefit of a third person, no one but the third person for whose benefit it is expressly made may avail himself thereof. On the estoppel theory, the representation is made only to the addressee; and it would seem that no one else may reason- ably rely on or act upon a representation expressly addressed to a " Tullis V. Jacson, [1892] 3 Ch. 441; Nolan v. Whitney, 88 N. Y. 648 (1882); Chicago R. Co. V. Price, 138 U. S. 185 (1891); Insurance Co. v. Pulver, 126 111. 329, 18 N. E. 804 (1888). ^2 Robbins v. Bingham, 4 Johns. (N. Y.) 476 (1809); Birckhead v. Brown, 5 Hill (N. Y.) 634; Walsh V. Bailee, 10 Johns. (N. Y.) 180 (1813). " Sollee V. Mengy, i Bailey, Law (S. C.) 620 (1830); Smith v. Montgomery, 3 Texas, 199 (1848); Crane v. Specht, 39 Neb. 123, 57 N. W. 1015 (1894).
