Appeal from a Trademark Trial and Appeal Board (board) decision, In re Clorox Co., 196 USPQ 140 (TTAB 1977), affirming the refusal of the examiner to register the designation ERASE for “laundry soil and stain remover.” We affirm.
Background
Appellant, The Clorox Company, filed an application1 to register ERASE on the Principal Register as a trademark for a laundry soil and stain remover. Use of the mark since November 13, 1975, was asserted. The examiner rejected the application on two grounds: (1) that ERASE so resembles STAIN ERASER previously registered for a stain remover2 as to be likely, when applied to applicant’s goods, to cause confusion or mistake, or to deceive, as proscribed by § 2(d) of the Lanham Act, as amended (Act), 15 U.S.C. § 1052(d) and (2) that ERASE is merely descriptive within the meaning of § 2(e)(1) of the Act. The board affirmed the examiner on both grounds.
The board noted that the language of § 2(d) is not restricted to marks registered on the Principal Register. Recognizing that registration on the Supplemental Register may indicate a merely descriptive significance, at least at time of registration, the board stated:
[Although registrations of highly suggestive or merely descriptive marks are entitled to some measure of protection against the registration of marks that may conflict therewith * * *, the scope is circumscribed by virtue of the character of the mark so that the permissible degree of similarity between the marks may be greater than in the case of arbitrary or coined terms. [196 USPQ at 143.]
The board considered ERASE and ERASER “virtually indistinguishable” and the addition of the descriptive word STAIN insufficient to avoid confusion when both marks are associated with a stain remover.
Issues
The issues are (1) whether a mark registered on the Supplemental Register can be used under § 2(d) as a basis for refusing registration of another mark on the Principal Register; and (2) whether simultaneous use of ERASE on a laundry soil and stain remover and STAIN ERASER on a stain remover would be likely to lead to confusion. 15 U.S.C. § 1052(d).3
OPINION
(1) Use Under § 2(d) of Marks Registered on the Supplemental Register
Appellant argues that marks on the Supplemental Register may not serve as a basis for refusal to register under § 2(d). We disagree.
*307In addressing this issue for the first time,4 we begin with the statute.5 Under § 2(d), the examiner and the board are charged with the duty of refusing registration of a mark, the use of which is “likely * * * to cause confusion * * *because of its resemblance to “a mark registered in the Patent and Trademark Office [PTO].” The definitional section of the Act, § 45, provides, in pertinent part:
The term “registered mark” means a mark registered in the United States Patent and Trademark Office under this chapter or under the Act of March 3, 1881, or the Act of February 20, 1905, or the Act of March 19, 1920. The phrase “marks registered in the Patent and Trademark Office” means registered marks. [15 U.S.C. § 1127]
Section 23 of the Act indicates that the Supplemental Register is “a continuation of the register provided in paragraph (b) of section 1 of the Act of March 19, 1920 * * * 15 U.S.C. § 1091. Section 26,15 U.S.C. § 1094, provides:
The provisions of this chapter shall govern so far as applicable applications for registration and registrations on the supplemental register as well as those on the principal register, but applications for and registrations on the supplemental register shall not be subject to or receive the advantages of sections 1052(e), 1052(f), 1057(b), 1062(a), 1063 to 1068, inclusive, 1072, 1115 and 1124 of this title. [Sections 2(e), 2(f), 7(b), 12(a), 13 to 18, inclusive, 22, 33, and 42 of the Act.]
Section 2(d)’s absence from the enumeration of statutory provisions made inapplicable to the Supplemental Register establishes unequivocally its applicability to “registrations on the supplemental register.”
That the decision respecting likelihood of confusion is made in the PTO by comparing an applicant’s mark and description of his goods with the registered marks on file in the PTO, and the goods described in the registrations of those marks, should not lead to the notion that the locus of potential confusion is in the files of the PTO.6 The confusion sought to be prevented by the statute is not that of examiners, lawyers, *308board members, or judges. Confusion is likely, if at all, only in the marketplace, where marks are used. The public is both unaware of, and distinctly disinterested in, whether a mark is registered on either register. Registration is itself incapable of causing confusion. Under § 2(d), the PTO is not charged with a duty of permitting or denying a right to use any mark, or of protecting any registered mark against the mere registration of similar marks (unless use of the latter would be likely to lead to confusion).
We conclude, therefore, that a mark registered on the Supplemental Register can be used as a basis for refusing registration to another mark under § 2(d) of the Act.7
(2) Likelihood of Confusion
Appellant says STAIN ERASER is merely descriptive, as evidenced by its presence on the Supplemental Register, and, because a merely descriptive term does not indicate origin, it cannot support a conclusion of likelihood of confusion. Though this court has referred to an application for Supplemental Registration of a particular term as an admission of descriptiveness, see Quaker State Oil Refining Corp. v. Quaker Oil Corp., 453 F.2d 1296, 1299, 59 CCPA 764, 767, 172 USPQ 361, 363 (1972), appellant’s argument ignores § 23 of the Act, under which marks registered on the Supplemental Register are required to be “capable of distinguishing applicant’s goods or services * * * 15 U.S.C. § 1091. Further, appellant disregards the existence of varying degrees of descriptiveness. Appellant erroneously attributes to marks on the Supplemental Register, a degree of “descriptiveness” equivalent to that of a generic or common descriptive word or term, and its argument that the merely descriptive nature of some marks on the Supplemental Register makes their use incapable of producing confusion is but another approach to the notion that marks on the Supplemental Register are not citable under § 2(d).8
In arguing that STAIN ERASER must be shown to have acquired a secondary meaning, before it can support a conclusion that confusion is likely, appellant again attempts to limit citations under § 2(d) to marks on the Principal Register, on which marks that have acquired a secondary meaning are registrable. 15 U.S.C. § 1052(f). Appellant appears also to suggest in this argument that the issue here should be resolved through publication of its mark and the possibility of an opposition by any person who believes he would be damaged by the registration. But § 2(d) imposes on the Commissioner the duty of refusing registration when he concludes that confusion, mistake, or deception, is likely, and the Act imposes on the Commissioner and on us the duty of making that subjective judgment. In re Apparel, Inc., 366 F.2d 1022, 1023, 54 CCPA 733, 734-35, 151 USPQ 353, 354 (1966). That duty is unaffected by the basis upon which a potential opposer may found an opposition. To require publication for opposition whenever a Supplemental Registration is cited under § 2(d), would result in an unwarranted diminution of the duty of ex parte trademark examination imposed upon the PTO by the Act.
Appellant next posits a requirement that citation of marks on the Supplemental Register under § 2(d) be limited to marks identical to that sought to be registered. No reason exists, however, for the application of different standards to registrations cited under § 2(d). The level of descriptiveness of a cited mark may influence the conclusion that confusion is likely or unlikely, see Sure-Fit Products Co. v. Saltzson Drapery Co., 254 F.2d 158, 160, 45 CCPA 856, 859, *309117 USPQ 295, 297 (1958), but that fact does not preclude citation under § 2(d) of marks on the Supplemental Register.
Regarding the conclusion that a likelihood of confusion is present, we agree with the board’s closing statement:
[T]he terms “ERASE” and “ERASER” are virtually indistinguishable and the addition of the descriptive word “STAIN” to “ERASER” is insufficient to distinguish between the marks as a whole and to avoid confusion because applicant’s “ERASE” mark is used in connection with and would be associated with a stain remover. [196 USPQ at 143.]
Conclusion
We conclude that marks on the Supplemental Register are citable under § 2(d), and that concurrent use of ERASE and STAIN ERASER on the goods named is likely to cause confusion, or mistake, or to deceive.
AFFIRMED.
. Serial No. 74,336, filed January 15, 1976.
. Reg. No. 1,035,099, dated March 2, 1976, on the Supplemental Register, use in commerce since March 11, 1974, having been asserted.
. We do not reach the alternative ground, i. e., that ERASE is merely descriptive. Appellant argues that neither the public nor the trade speaks of “erasing” stain or soil from laundry, citing dictionary definitions for “erase.” The Supplemental Registration of STAIN ERASER, however, demonstrates that at least one party in the trade uses a variant of ERASE in connection with a stain remover product.
. The board has consistently concluded that a mark registered on the Supplemental Register is “a mark registered in the Patent and Trademark Office” within the meaning of 15 U.S.C. § 1052(d), In re Amtel, Inc., 189 USPQ 58 (TTAB 1975); In re Hunke & Jochheim, 185 USPQ 188 (TTAB 1975); In re Knight’s Home Products, Inc., 173 USPQ 566 (TTAB 1972), as has the Commissioner. See Ex parte Auto-Lite Battery Corp., 114 USPQ 500 (Comm’r 1957); Ex parte Jacobson & Sons, Inc., 97 USPQ 465 (Comm’r 1953). Cf. Hess v. Helene Curtis Industries, Inc., 94 USPQ 11 (Comm’r 1952). The solicitor cites Standard Int'l. Corp. v. American Sponge and Chamois Co., Inc., 394 F.2d 599, 55 CCPA 1155, 157 USPQ 630 (1968). That case, however, involved an opposition, wherein the opposer relied upon sales volume and promotion expenditures relating to its mark on the Supplemental Register. Whether a mark registered on the Supplemental Register is a “mark registered in the Patent and Trademark Office” under 15 U.S.C. § 1052(d) was not at issue.
. The pertinent statutory language reads:
No trade-mark by which the goods of the applicant may be distinguished from the goods of others shall be refused registration on the principal register on account of its nature unless it—
(d) Consists of or comprises a mark which so resembles a mark registered in the Patent and Trademark Office or a mark or trade name previously used in the United States by another and not abandoned, as to be likely, when applied to the goods of the applicant, to cause confusion, or to cause mistake, or to deceive * * *. [15 U.S.C. § 1052(d)]
The board opinion, quoted above, refers to “protection [of marks] against the registration of marks that may conflict therewith.” The “protection” envisaged by § 2(d) is not that of marks against the mere registration of other marks. Hence, the “conflict” must occur in the marketplace. Moreover, a refusal to register even a “conflicting” mark does not “protect” a registered mark against use of the conflicting mark in the marketplace. In re E.I. duPont deNemours & Co., 476 F.2d 1357, 1364, 177 USPQ 563, 569 (Cust. & Pat.App.1973). Users of trademarks and owners of registrations, when they seek “protection of their marks” are necessarily protecting their right to an unconfused public, and are thus serving the statutory goal of protecting the public against confusion, mistake or deception. The sole duty of the examiner, the board, and this court, under § 2(d), is to determine whether confusion is likely.
. The language of the Act being clear and unambiguous, resort to legislative history is unnecessary. Interested parties will find an excellent summary of the legislative history in the footnote to Examiner-in-Chief Federico’s opinion in Ex parte Jacobson & Sons, Inc., supra.
. Appellant has a cancellation proceeding available under 15 U.S.C. § 1092, if registrant was not entitled to registration because the mark is a common descriptive term and thus incapable of indicating origin of the goods, or because the mark is not used by the registrant or has been abandoned.