specially concurring:

While I join in the result reached by Judge Renfrew, I cannot concur in his reasoning in concluding that Section 605, 47 U.S.C. § 605 (1976), does not prohibit the use of pen registers and that the Fourth Amendment does not restrict the use of a pen register.

I

The problem presented by this appeal is one of interpretation: Did Congress intend to permit or prohibit pen registers under Section 605? This process of interpretation requires us to explore both legislative history and the judicial reception to pen registers under Section 605. While Judge Ren-frew’s analysis may offer a reasonable interpretation of Section 605’s applicability to pen registers, it does not accurately represent the judicial response to pen registers under Section 605. In its failure to do so, Judge Renfrew’s analysis skips over a crucial analytical stepping stone in arriving at a fair interpretation of Congress’ intent with respect to pen registers under Section 605.

Pen registers have had a diverse history under Section 605. Prior to its amendment in 1968, Section 605 contained two clauses applicable to pen registers. Clause 1 pro *262 hibited, with certain exceptions inapplicable here, a telephone company employee who assisted in the transmission of a wire or radio communication from divulging the “existence, contents, substance, purport, effect, or meaning” of that communication. Clause 2 proscribed any person from intercepting and divulging the “existence . . or meaning” of a wire or radio communication except as authorized by the sender. 1

Judge Renfrew states that because pen registers involve interceptions, only clause 2 of pre-1968 Section 605 applied to pen registers. Thus, after the 1968 Amendments removed clause 2’s applicability to wire communications, Section 605 no longer regulated the use of pen registers. By characterizing pen registers as interceptions, Judge Renfrew forecloses any consideration of whether clause 1 prohibits pen registers. Presumably, Judge Renfrew finds this question academic because he concludes that “[t]he first clause of the pre-1968 § 605 never regulated the use of pen registers[.]” But, contrary to Judge Renfrew’s assertions, not all courts characterized pen registers as interceptions and several courts used clause 1 to consider the validity of pen registers both prior to and after the 1968 Amendments to Section 605.

Before Section 605 was amended, courts employed both clauses 1 and 2 to strike down pen registers. In United States v. Caplan (E.D.Mich.1966) 255 F.Supp. 805 , the court held that clause 1 was violated when the telephone company installed a pen register after the I.R.S. had sought its aid in investigating a suspected gambling operation. Although a pen register tape merely records those numbers dialed from a particular telephone and does not indicate whether the calls were completed, the Caplan court found that the tape was a communication under Section 605 because the number of telephone rings could have been a “pre-arranged” signal for the receiving party. To divulge the contents of the tape would be to disclose the existence of a communication and thereby to transgress clause 1 of Section 605. (“The pen register recordation may reveal the ‘existence’ of a communication even though the pen register does not indicate whether or not the call was completed.” Id. at 808 .)

As merely an alternative basis for its holding, the district court in the Caplan case concluded that a pen register constituted an interception prohibited by clause 2 of Section 605. (See also United States v. Dote (7th Cir. 1966) 371 F.2d 176 ; United States v. Guglielmo (N.D.Ill.1965) 245 F.Supp. 534 , aff’d in Dote, supra. But cf. United States v. Gallo (2d Cir. 1941) 123 F.2d 229, 231 (Where the court upheld the disclosure of the defendant’s telephone records in a prosecution for tax fraud because telephone records did not involve an interception under clause 2: “. . . When a person takes up a telephone he knows that the company will make, or may make, some kind of a record of the event, and he must be deemed to consent to whatever record the business convenience of the company requires.”).)

Section 605 received a legislative face-lift in Title III of the Omnibus Crime Control Act of 1968, Pub.L. No. 90-351, § 803 , 82 Stat. 223 (1968). 2 Clause 2 was amended to *263 prohibit only the interception of radio communications. The courts that had treated pen registers as prohibited interceptions under clause 2 before 1968, now concluded that Section 605 no longer proscribed interceptions of wire communications by pen registers. (See United States v. Brick (8th Cir. 1974) 502 F.2d 219, 223 ; United States v. Falcone (3d Cir. 1974) 505 F.2d 478, 482 ; Korman v. United States (7th Cir. 1973) 486 F.2d 926, 932 ; Application of the United States in the Matter of an Order Authorizing the Use of a Pen Register or Similar Mechanical Device (2d Cir. 1976) 538 F.2d 956, 958-59 , cert, granted, 429 U.S. 1072 , 97 S.Ct. 807 , 50 L.Ed.2d 789 (1977) (“It is also clear that pen register orders are not now covered by Section 605 . . . . Pri- or to the enactment of Title III, there was authority for the broad applicability of Section 605 to the interception and disclosure of ‘any communication,’ including pen registers. . . . The amendment of Section 605 . . . withdrew the interception of wire . . . communications from the ambit of that Section, making Title III the sole governing provision.”).) This reasoning was bolstered by the Senate Report accompanying Title III which commented that interceptions of wire communications were now covered by the Omnibus Crime Control Act (i. e., 18 U.S.C. §§ 2510-2520 (1976)). (“. . . The regulation of the interception of wire or oral communications in the future is to be governed by proposed new chapter 119 of title 18, United States Code.” S.Rep. No. 1097, 90th Cong., 2d Sess. (1968), as reprinted in [1968] U.S.Code Cong. & Admin.News pp. 2112, 2196 [“Senate Report”].)

On the other hand, Congress made only cosmetic changes in amending clause 1. Judge Renfrew’s analysis would stop here. Because Congress did not intend to expand clause 1 to regulate interceptions when it amended Section 605, Judge Renfrew concludes that Section 605 has no continued applicability to pen registers. This rationale ignores those cases that do not characterize pen registers as interceptions, and thus does not take into account cases, including the only one from this Circuit, that have looked to clause 1, as amended, to determine the validity of pen registers.

Because neither the Omnibus Crime Control Act nor clause 2 of Section 605 was applicable to pen registers after 1968, courts were forced to focus on clause 1 to consider the legality of pen registers. Although one court squarely held, in a telephone harassing prosecution, that the use of a pen register violated clause 1 (see Commonwealth v. Coviello (1973) 362 Mass. 722 , 291 N.E.2d 416 ), the courts generally found that the particular uses of a pen register before them came within one of the exceptions to clause 1 enumerated in that clause. In those cases it was unnecessary to decide whether clause 1, as amended, prohibited pen registers. (See United States v. King (S.D.Cal.1971) 335 F.Supp. 523, 549 , aff’d in part and rev’d in part on other grounds (9th Cir. 1973), 478 F.2d 494 (After noting that the Caplan court found that pen registers violated clause 1 and that clause 2 no longer applies to pen registers after the 1968 Amendments, the court observed, “[t]his would serve to remove pen register coverage from the second clause and include it, if at all, within the first clause. This Court believes that divulgence ‘on demand of other lawful authority’ must include disclosure pursuant to a search warrant issued under Rule 41 of the Federal Rules of Criminal

*264 Procedure.”); United States v. Lanza (M.D. Fla.1972) 341 F.Supp. 405, 422 (Where the court found it unnecessary to decide whether clause 1 of Section 605, as amended, prohibits pen registers because it held that when a pen register was used in conjunction with a court-ordered wiretap, the court-ordered wiretap was sufficient to permit the use of the pen register. It did note that Caplan “may still be efficacious.”); United States v. Finn (7th Cir. 1974) 502 F.2d 938, 942-43 (After recognizing that clause 2 no longer applies to pen registers, the court considered the defendants’ claims under clause 1. “We come then to the heart of the problem. The first sentence of Section 605 appears on its face to forbid divulgence of any communication to any of six groups of persons. . . . Facially, it would appear that Congress has absolutely forbidden the divulgence of pen register records, e. g., in response to a subpoena or on demand of other lawful authority . . . . Such a literal result would be at war with the Congressional intent to permit pen registers. So construed, Section 605 .does not forbid the pen registers at issue here. A search warrant supported by probable cause is a ‘demand of other lawful authority’ within exception (6).”); Note, The Legal Constraints Upon the Use of the Pen Register as a Law Enforcement Tool (1975) 60 Cornell L.Rev. 1028, 1036.)

In spite of these prior pronouncements, clause 1 of Section 605 should not be read to prohibit the use of pen registers. Congress intended that once amended, Section 605 would act as a substitute provision for its pre-1968 predecessor. (“ . . . This section is not intended merely to be a reenactment of section 605. The new provision is intended as a substitute.” [1968] U.S.Code Cong. & Admin.News, at p. 2196.) Thus, the authority of those cases that suggest that clause 1 prohibits pen registers is diminished.

When Congress amended Section 605 in Title III of the Omnibus Crime Control Act, it included within the same Title a wholly new statutory scheme for the interception and disclosure of wire communications (i. e., 18 U.S.C. §§ 2510-2520 ). The legislative history of these new provisions clearly evidences Congress’ intent to permit pen registers. (“. . . The proposed legislation is not designed to prevent the tracing .of phone calls. The use of a ‘pen register,’ for example, would be permissible.” Senate Report in [1968] U.S.Code Cong. & Admin. News at p. 2178.) In concluding that the new statute would not prohibit pen registers, Congress must have assumed that their use was also permissible under the older statute. 3 Additionally, Congress wanted to Omnibus Crime Control Act to take over the regulation of wire communication interceptions and electronic surveillance. 4 (See Falcone, supra, at p. 482 (“[T]he legislative history of the 1968 Amendment to § 605 reveals that Congress intended to shift all control of electronic surveillance operations to 18 U.S.C. §§ 2510-2520 .”); Korman, supra, at p. 932 .) This intent would be thwarted if clause 1 of Section 605 were interpreted to apply to pen registers.

Finally, the cases that have prohibited pen registers have, for the most part, arisen in the context of criminal prosecutions for acts totally unrelated to the delivery of telephone service. These cases typically in *265 volve the telephone company’s use of a pen register at the request of the Government to aid in the Government’s investigation of crimes that do not relate to the telephone company’s delivery of service to its customers. We are not faced with such a case in the present appeal.

From the infant years of Section 605 on, courts have recognized exceptions to the prohibitions in both clauses 1 and 2 of Section 605 where the telephone company has confined its use of the pen register to protecting itself against fraud or abuse of its facilities. (See United States v. Goldstein (9th Cir. 1976) 532 F.2d 1305, 1309 (“. . Despite these restrictions [i. e., Section 605’s] ... it was held in a number of cases that § 605 did not prohibit a telephone company from monitoring its own lines to protect the integrity of its regular billing.”); Bubis v. United States (9th Cir. 1967) 384 F.2d 643, 648 (“We do not believe that in the enactment of Section 605 . Congress intended to deprive communications systems of their fundamental right to take reasonable measures to protect themselves and their properties against the illegal acts of a trespasser.”).) Indeed, at its inception, Section 605 was drafted “to protect the integrity of communications systems[.]” (Bubis, at p. 646.) Included within this integrity is the obligation of the telephone company to shield its customers from the abuse of their telephone service by those who make obscene telephone calls. It is noteworthy that the customer was the paramount concern of Congress in drafting both versions of Section 605. (See United States v. Russo (E.D.Pa.1966) 250 F.Supp. 55, 58 (“The purpose of section 605 is to prohibit blatant public or private encroachments on the privacy of messages and the integrity of communication systems.” (footnote omitted)).) With such a birthright, it would be anomalous indeed if Section 605 were interpreted to deprive a victim of obscene telephone calls of the very same protection Section 605 permits the telephone company itself to use against loss of profits. 5

II

I cannot join in the reasoning of Part I of Judge Renfrew’s opinion. I assume, ar-guendo, that appellant can show the requisite governmental action to state a claim *266 for relief under Section 1983; we reach the constitutional issue only because we conclude that appellee’s installation of a pen register does not transgress any federal statutory prohibition. In my view, the employment of a pen register in the present case does not constitute a search within the meaning of the Fourth Amendment because the “electronic listening” does not encroach upon “the privacy upon which [one] justifiably reliefs]”. (Katz v. United States (1967) 389 U.S. 347, 353 , 88 S.Ct. 507, 512 , 19 L.Ed.2d 576 ; United States v. Baxter (9th Cir. 1973) 492 F.2d 150, 167 .)

A pen register records the numbers dialed from a particular telephone. It does not disclose the contents of any conversation nor does it indicate whether any calls were completed. So described, a pen register tape contains similar information to that which is recorded by the telephone company for purposes of billing toll calls. In Baxter, supra, we upheld the disclosure of telephone company billing records against a Fourth Amendment challenge. We noted that there was no justifiable expectation of privacy in the contents of these records: “Telephone subscribers are fully aware that records will be made of their toll calls. . This Court has held that the expectation of privacy protected by the Fourth Amendment attaches to the content of the telephone conversation and not to the fact that a conversation took place.” (Id. at p. 167. See also United States v. Fithian (9th Cir. 1971) 452 F.2d 505, 506 (“. . . No one justifiably could expect that the fact that a particular call was placed will remain his private affair when business records necessarily must contain this information.” (footnote omitted)).) Similarly, there is no expectation of privacy in the contents of a pen register tape. Like billing records, a pen register tape discloses the numbers dialed from a particular telephone and not the contents of any conversation. In fact, a pen register creates a lesser intrusion into a subscriber’s privacy because, unlike billing records, a pen register tape does not indicate whether any calls were answered.

True, the telephone company usually does not keep a record of local telephone calls. But most subscribers are unaware of the boundaries of their local dialing zones, especially in cities where these zones do not coincide with traditional geographic boundaries. Furthermore, it is common practice for the telephone company to keep a record of all calls dialed from a telephone which is subject to a special rate structure. (See 60 Cornell L.Rev. at p. 1045, n.96.) Under these circumstances, subscribers do not harbor any justifiable expectation of privacy that a record will not be kept of their outgoing calls. 6 (See United States v. Clegg (5th Cir. 1975) 509 F.2d 605, 610 (“. . . The Fourth Amendment protects only the content of a telephone conversation and not the fact that' a call was placed or that a particular number was dialed. . . . This is so because telephone subscribers have no reasonable expectation that records of their calls will not be made. It is, in fact, well known that such records are kept. . . For this reason, the acquisition ... by means of a pen register ... of nothing more than information concerning . the numbers dialed does not offend the Fourth Amendment.”).) 7

*267 The decision in this ease is a narrow one. We do not hold that information recorded by pen registers is never entitled to Fourth Amendment protection. Rather, our holding that the telephone company’s use of a pen register to investigate obscene telephone calls does not violate the Fourth Amendment is limited to the facts presented by this appeal. We leave for another day a Fourth Amendment challenge to the telephone company’s installation of a pen register at the request of the Government to investigate a crime that is unrelated to the delivery of telephone service.

. Section 605, prior to its amendment, stated in part:

. Section 605, as amended, provides, in part:

. If this were not the case, Congress would have, at the very least, included a citation to Section 605 to indicate that Section 605 was still available to attack pen registers. The Senate Report’s reference to Dote following its language permitting the use of pen registers under the Omnibus Crime Control Act does not alter this conclusion. Dote clearly has no continued vitality under the amended clause 2 to Section 605. Nor does Dote discuss the applicability of clause 1 to pen registers.

. The dissent distinguishes between the Omnibus Crime Control Act and Section 605 by arguing that the former statute deals with eavesdropping by interceptions while the latter is concerned with the divulgence of information regardless of how the information is obtained. The distinction is unsound. The second clause of Section 605 still deals with interceptions, albeit only of radio communications. And the Omnibus Crime Control Act, as well as Section 605, prohibits the disclosure of certain wire communications. (See 18 U.S.C. § 2511 (1)(c).)

. My brothers criticize my reference to those cases in this Circuit that have exempted from Section 605’s prohibitions the use of pen registers to detect billing fraud. They argue that we should not expand 18 U.S.C. § 2511 (2)(a)(i) (1977) or the rationale of Bubis to permit a telephone company’s investigation of obscene telephone calls because such an expansion would also condone a telephone company’s investigation of extortion and like crimes. First, my discussion of the billing fraud cases is not intended to be interpretative of Section 2511(2)(a)(i) or of Bubis and its progeny. It is offered merely to support, by way of analogy, my conclusion that Section 605 does not prohibit the use of a pen register in the present suit. Our task is one of interpretation and my inclusion of the billing fraud cases requires us seriously to question any interpretation of Section 605 that would empower a telephone company to use a pen register to protect its bank account, but not to protect its customers against obscene telephone calls.

Second, my brothers envision a parade of horri-bles marching to the tune of my “dictum.” Their concern is misplaced. A telephone user is not remediless against a telephone company turned private investigator. Part II of my opinion carefully preserves an injured customer’s remedies under the aegis of the Fourth Amendment if a telephone company uses pen registers to assist the police in the investigation of non-service related crimes. While making obscene telephone calls may be a crime, it also threatens the quality of the telephone company’s delivery of service (i. e., a victim may, as a result of receiving such calls, refuse to pick up his telephone or may discontinue service altogether). Thus, in contrast to those situations where the use of a telephone merely supplies the jurisdictional component for the application of a federal criminal statute, a telephone company has an interest to protect when a telephone is used to make obscene telephone calls. Nor does the opinion threaten the validity of a customer’s remedy under 42 U.S.C. § 1983 (1974) or under the rationale of Bivens v. Six Unknown Named Agents of Federal Bureau of Narcotics (1971) 403 U.S. 388 , 91 S.Ct. 1999 , 29 L.Ed.2d 619 if, assuming the appropriate governmental participation is present, the telephone company uses a pen register to investigate non-service related crimes. Furthermore, one injured by the disclosure of information gleaned from the over-zealous use of a pen register may still have a remedy against the telephone company under state law for unprivileged invasion of privacy.

. Our conclusion is not altered by the holdings in Application of the United States for an Order Authorizing Installation and Use of a Pen Register v. Southwestern Bell Telephone Company (8th Cir. 1976) 546 F.2d 243 , cert, petition died (February 22, 1977) 45 U.S.L.W. 3638 , and Application of the United States In the Matter of an Order Authorizing the Use of a Pen Register or Similar Mechanical Device (2d Cir. 1976), supra. In those cases, the issue of whether the use of a pen register constitutes an unconstitutional search under Katz never arose because the Government had procured a court order to install the pen register prior to its attachment. The main issue in those cases was whether the Government could use a court order to force the telephone company to assist the Government in its investigation of non-service related crimes.

. To the extent that Judge Renfrew implies that today’s holding with respect to the legality of pen registers under the Fourth Amendment extends to the question of the constitutional validity of a TTS 176 device or a “snifter”, it is impermissible dictum.