GEE, Circuit Judge:
In this criminal case, the government appeals the pretrial dismissal of an eleven-count indictment against businessmen Thomas M. (“Mick”) Hajecate and Thomas H. (“Tom”) Hajecate and their tax attorney, Lance Eisenberg. The defendants Hajecate cross-appeal the district court’s denial of their motion to dismiss the indictment based on prosecutorial vindictiveness.
I. FACTS AND DISPOSITION BELOW.
On January 21, 1981, a grand jury in the Southern District of Texas returned an eleven-count indictment, charging the three defendants with violations of several federal criminal laws.1 All these violations stemmed from a scheme to conceal the Hajecates’ interest in an offshore (Cayman Islands) bank account. As gleaned from the indictments, part and parcel of this scheme were obstruction of IRS tax collection, false statements on income tax returns, failure to report financial transactions between persons in the United States and foreign institutions to the Customs Service, and. unreported transfers of money between the United States and the Cayman Islands. We shall give more details on the counts as necessary in our discussion of the issues on appeal. On February 25, 1981, a superseding indictment covering the same scheme and containing the same number of counts was filed.
The defendants sought bills of particulars on the indictment and moved for its dismissal as well. After a March 18, 1981, hearing, the district court dismissed all eleven counts as facially invalid, accepting “the Defendants’ theory of law in every respect” except the allegation of prosecutorial vindictiveness.
II. THE GOVERNMENT’S APPEAL.
A. Count One.
Count one charged all three defendants with violating the federal criminal conspiracy statute, 18 U.S.C. § 371 (1976). This alleged conspiracy had four objects, all violations of federal law: (1) defrauding the United States by obstructing the IRS in its collection of income taxes; (2) defrauding the United States by obstructing Customs Service maintenance of records of financial transactions between foreign financial institutions and United States citizens; (3) knowingly and willfully making false statements on income tax returns; and (4) failure to report money transferred between the United States and the Cayman Islands. The defendants attacked the indictment’s statement of each object as facially invalid, and we address each object in turn.
Obstruction of the IRS
In attacking the first object, the defendants claim that two transactions named as means and methods of furthering the conspiracy, a loan obtained by one of the Hajecates’ oil companies and .silver straddles engaged in by the Hajecates, are in fact legal transactions. Therefore, since these transactions are equally capable of legal interpretation, the indictment is invalid because it does not state an offense. See Standard Oil Co. v. United States, 307 F.2d 120, 130 (5th Cir. 1962). The government responds that the indictment does not allege that these transactions were illegal in and of themselves but that they lost their legal character because they were used to bring about the unlawful object of the scheme, obstruction of the IRS.
The government’s position is correct: “it is well settled that acts which are themselves legal lose their legal character when they become constituent elements of an un[897]*897lawful scheme.” Continental Ore Co. v. Union Carbide Corp., 370 U.S. 690, 709, 82 S.Ct. 1404, 1415, 8 L.Ed.2d 777 (1962). Thus, these transactions are not “equally” capable of legal interpretation, and the government is not, as defendants’ claim, testing the legality of silver straddles in this case. In the context of count one’s allegation of conspiracy and recital of other illegal acts, these two transactions lose their legal character and do not render count one invalid.
Next, the defendants allege that count one failed to particularize the alleged scheme.
The test to determine the sufficiency of an indictment is well established. An indictment is sufficient if it contains the essential elements of the offense so that it fairly informs the defendant of the charges against him and if it adequately enables the defendant to be protected against further prosecution for the same offense. Furthermore, an indictment is to be read in light of its purpose, which is to inform the accused of the charges against him. Its validity is governed by practical, not technical, considerations.
United States v. Mouton, 657 F.2d 736, 739 (5th Cir. 1981) (per curiam) (citations omitted). Conspiracy indictments have been given particularly careful scrutiny:
It is our affirmative duty to carefully scrutinize indictments under the broad language of the conspiracy statute because of the possibility, inherent in a criminal conspiracy charge, that its wide net may ensnare the innocent as well as the guilty.
United States v. Porter, 591 F.2d 1048, 1057 (5th Cir. 1979).
In examining a conspiracy indictment, the first test is to ascertain whether it goes beyond the generic terms of 18 U.S.C. § 371 and the statutes violated by the conspiracy to allege specific details about the scheme. See Van Liew v. United States, 321 F.2d 664, 669-74 (5th Cir. 1963). The IRS obstruction claim easily passes this test. A concise paragraph makes the allegation, and numerous “overt acts” and “means and methods are cited in support in the remainder of count one. This has rendered count one longer and more complex than the other counts, yet it is still the plain and concise statement required by Fed.R.Crim.P. 7, since it outlines the essential elements of the complex conspiratorial scheme charged against the defendants. Unnecessary detail not found in count one was made available to defendants through two lengthy bills of particulars.
Defendants posit several specific failures to particularize that we must address. First, they claim that an allegation of Eisenberg’s purpose in obstructing the IRS is fatally lacking. This argument has no merit. Eisenberg is clearly alleged to be a conspirator, and he thereby shares the purposes of the conspiracy, which are also clearly alleged in the indictment.
Second, defendants claim a lack of clarity as to whose taxes the IRS was obstructed from ascertaining. This lack of clarity allegedly arises from reading the indictment and the government’s answers to a bill of particulars. The government responds that the indictment reveals that the taxes at issue are those of the Hajecates and that the four corporations that they allegedly owned were used in the obstruction. Thus, the government stated in response to the bill of particulars that the IRS obstruction charge involved all six taxpayers.
We see no flaw here. The defendants see an inconsistency between the indictment and the bill of particulars where none exists. They are clearly on notice from the indictment that the obstruction charge goes to the Hajecates’ taxes only and that the four corporations were used to conceal those taxes.
Even if the bill was inconsistent with the indictment, the proper remedy is not dismissal of the indictment but clarification of the bill. The indictment here, unless properly amended or superseded, constitutes the full statement of the charges against the defendants. They face no additional jeopardy from a bill, since it cannot be used to amend an indictment, see [898]*898United States v. Willoz, 449 F.2d 1321, 1323 (5th Cir. 1971). It is the government that suffers if the bill goes beyond the indictment and improperly adds new charges. Thus, any inconsistency here does not harm the defendants in a constitutional sense, since the indictment is clear and determines the issues of notice and jeopardy.2
Finally, the defendants complain of ambiguity in the definitions of several terms in the indictment — “shell company,” “affiliates,” and “utilized and controlled.” We believe that they are clear in their contexts and that any ambiguity does not rise to the level of a constitutional defect. Therefore, the appropriate remedy is to request a bill of particulars, not dismiss the indictment.
Overall, then, there is no defect in the first object of count one. What the defendants seek, in many of their allegations is essentially the disclosure by the government of its full theory of the case and all the evidentiary facts to support it. That is not and never has been required at the indictment stage — the only requirements are notice to the defendants and preclusion of double jeopardy. The government need do no more in the indictment. The ready remedy of a motion for a bill of particulars is available to add specifics beyond those required for the indictment to pass constitutional muster, see United States v. Williams, 203 F.2d 572, 574 (5th Cir.), cert. denied, 346 U.S. 822, 74 S.Ct. 37, 98 L.Ed. 347 (1953), although, of course, even a bill of particulars cannot be required to compel revelation of the full theory of the case or all the evidentiary facts, see United States v. Murray, 527 F.2d 401, 411 (5th Cir. 1976); United States v. Bonnet, 247 F.Supp. 415, 417 (E.D.La.1966) (Ainsworth, J.). We conclude that the government has fulfilled its duty here in presenting a constitutionally adequate indictment under object one and in voluntarily furnishing two bills of particulars to assist the defendants.
Obstruction of the Customs Service
Defendants repeat their allegation of generic pleading as to this object. This allegation has no more merit against this object than it did against the object of obstruction of the IRS. The object is stated in a concise paragraph and supported by a lengthy list of overt acts and means and methods. We do not examine particular paragraphs of an indictment out of the context of the remainder of the indictment. See United States v. Hand, 497 F.2d 929, 934-35 (5th Cir. 1974), adopted on rehearing en banc, 516 F.2d 472, 477 (1975), cert. denied, 424 U.S. 953, 96 S.Ct. 1427, 47 L.Ed.2d 359 (1976). As we have oft repeated, an indictment’s validity “is governed by practical, not technical, considerations.” United States v. Varkonyi, 645 F.2d 453, 456 (5th Cir. 1981).
Contrary to defendants’ claim that “none” of the alleged overt acts relate to obstruction of the Customs Service, we find that several do. The list of means and methods references this object, and this list is suffiently detailed to make it quite easy to ascertain which overt acts are involved in this object. This claim has no merit.
Finally, the defendants allege improper “pyramiding” of offenses under this object. This claim requires some explanation. Usually, withholding information from the Customs Service under 31 U.S.C. § 1121 is a misdemeanor. However, when done in furtherance of another offense it becomes a felony. See 31 U.S.C. §§ 1058, 1059. The government charges in count one that the section 1121 violation was in furtherance of a violation of both 18 U.S.C. §§ 371 and 1001. However, the defendants claim that the government has alleged no false statement in violation of section 1001; therefore, the charge is really a conspiracy in furtherance of a conspiracy, which is an impermissible pyramiding of charges.
Defendants’ logic has a fatal flaw: the government has alleged a section 1001 violation. Section 1001 renders illegal inten[899]*899tional falsification and concealment, as well as false statements. The indictment clearly alleges intentional concealment of information that should have been reported to the Customs Service: “defendants concealed] their [foreign bank account] from the ... United States Customs Service.” (emphasis added).
This object is therefore valid in its entirety.
False Statements on Income Tax Returns
Defendants’ success in attacking this object is predicated on the success of their attack on counts two through five, which contain the allegations of offenses under the false statement statute, 18 U.S.C. § 1001. Since we find these counts invalid, infra, this object is also invalid.
Transfer of Currency Between the United States and the Cayman Islands
This object is valid in its entirety.
Conclusion
Since in order to prosecute a conspiracy successfully the government must be able to point out two separate provisions, one making the act of conspiring a crime and another making the object of the conspiracy a crime, see United States v. Meacham, 626 F.2d 503, 507 (5th Cir. 1980), the government may not prosecute this conspiracy indictment under object three, which we have held invalid. However, the government may proceed on objects one, two, and four.
B. Counts Two through Five.
On their 1976 and 1977 income tax returns, the Hajecates concealed their offshore bank account by answering the following question “no”: “Did you at any time during the taxable year have any interest in or signature or other authority over a bank, securities, or other financial account in a foreign country . .. ? Yes-No- If ‘yes’ attach Form 4683 (for definitions, see Form 4683).” Counts two through five indict the Hajecates for making false statements to a government agency in violation of 18 U.S.C. § 1001, and indict Eisenberg for aiding and abetting them in violation of 18 U.S.C. § 2.
The defendants attack counts two through five in several ways. We find merit in one and uphold the dismissal of these counts.
When the government properly exercised its discretion and chose to indict the Hajecates under the general statute making false statements a federal crime, 18 U.S.C. § 1001, instead of under 26 U.S.C. § 7206 of the Internal Revenue Code, which specifically penalizes false statements on tax returns, it of course invoked all the precedent under section 1001. Part of that precedent is the “exculpatory no” doctrine formulated in this circuit in Paternostro v. United States, 311 F.2d 298 (5th Cir. 1962). In Paternostro this court reversed a conviction under section 1001 of a man who allegedly knowingly and willfully made a false statement to an IRS special agent. This false statement was made under oath during investigative questioning by the agent. After reviewing the origins and history of the statute and surveying the case law, see id. at 301-05, the court in Pasternostro derived principles to guide the application of section 1001; a section designed primarily to prevent fraudulently obtaining claims, privileges, or employment from the United States. For liability to attach under section 1001, the defendant must “aggressively and deliberately initiate ... [a] positive or affirmative statement calculated to pervert the legitimate functions of Government.” Id. at 305. “[M]ere negative responses to questions ... by an investigating agent . .. not initiated by the appellant” are not actionable under section 1001. Id.
This doctrine has evolved and spawned considerable progeny. In United States v. Bush, 503 F.2d 813 (5th Cir. 1974), this court dismissed a section 1001 indictment based on a taxpayer’s signing of affidavits prepared by IRS officials that contained false statements. The taxpayer’s signature was held to be essentially an “exculpatory no.” In United States v. Schnaiderman, 568 F.2d [900]*9001208 (5th Cir. 1978), we held an oral denial to a question put to a defendant by a Customs agent on the defendant’s arrival in the United States to invoke the doctrine.
Since the Hajecates made “mere negative responses” and in no way made an “aggressive” or “deliberate positive or affirmative statement,” the question presented here is whether an “investigation” was occurring when the Hajecates answered that question on their tax returns. If so, the doctrine applies, and counts two through five fail.
The government claims that in all the “exculpatory no” cases an individual was singled out by a government official acting in a police capacity, e.g., an IRS agent, a Customs agent, magistrate, and so forth. This case is distinguishable, argues the government, since the question on the tax form applied to all similarly situated individuals: the Hajecates were not singled out for investigation. Therefore, there was no coercion or intimidation of the Hajecates, no confrontation that threatened their rights. Finally, the government points to the Supreme Court’s characterization of income tax return questions as “neutral on their face,” “not directed at those ‘inherently suspect of criminal activities,” and not involving “the compulsion to incriminate.” Garner v. United States, 424 U.S. 648, 660-61, 96 S.Ct. 1178, 1185-86, 47 L.Ed.2d 370 (1976).
However, defendants point out that this question is a novel one on the tax form: it has absolutely nothing to do with the calculation of one’s taxes. Thus it is in a kind of limbo, not “investigative” in the traditional sense of the “exculpatory no” doctrine, yet obviously not administrative. Seeking to characterize the nature of this question, we turn to the statute authorizing it, 31 U.S.C. § 1121, the regulation implementing the statute, 31 C.F.R. § 103.24 (1977), and the legislative history undergirding both.
The statute declares:
(a) The Secretary of the Treasury, having due regard for the need to avoid impeding or controlling the export or import of currency or other monetary instruments and having due regard also for the need to avoid burdening unreasonably persons who legitimately engage in transactions with foreign financial agencies, shall by regulation require any resident or citizen of the United States or person in the United States and doing business therein, who engages in any transaction or maintains any relationship, directly or indirectly, on behalf of himself or another, with a foreign financial agency to maintain records or to file reports, or both, setting forth such of the following information, in such form and in such detail, as the Secretary may require:
(1) The identities and addresses of the parties to the transaction or relationship.
(2) The legal capacities in which the parties to the transactions or relationships are acting, and the identities of the real parties in interest if one or more of the parties are not acting solely as principals.
(3) A description of the transaction or relationship including the amounts of money, credit, or other property involved.
(b) No person required to maintain records under this section shall be required to produce or otherwise disclose the contents of their records except in compliance with a subpoena or summons duly authorized and issued or as may otherwise be required by law.
The Secretary of the Treasury has elected to obtain these “reports” as part of the annual federal income tax returns required of all citizens:
Each person subject to the jurisdiction of the United States (except a foreign subsidiary of a U. S. person) having a financial interest in, or signature or other authority over, a bank, securities or other financial account in a foreign country shall report such relationship as required on his Federal income tax return for each year in which such relationship exists, and shall provide such information concerning each such account as shall be specified in a special tax form to be filed by such person.
[901]*90131 C.F.R. § 103.24 (1977). The Supreme Court has characterized the purpose of the Bank Secrecy Act of 1970, of which section 1121 is a part, as follows: “The express purpose of the Act is to require the maintenance of records, and the making of certain reports, which ‘have a high degree of usefulness in criminal, tax or regulatory investigations or proceedings.’ ” California Bankers Association v. Schultz, 416 U.S. 21, 26, 94 S.Ct. 1494, 1500, 39 L.Ed.2d 812 (1974), quoting 12 U.S.C. §§ 1829b(a)(2), 1951; 31 U.S.C. § 1051. This characterization is amply supported by the legislative history of the Act, where we find a presumption by Congress that secret foreign bank accounts and secret foreign financial institutions are inevitably linked to criminal activity in the United States. See H.R.Rep. No.975, 91st Cong., 2d Sess. 4-5 (1970), reprinted in 1970 U.S.Code Cong. & Ad. News 4394, 4397-98; S.Rep.No.1139, 91st Cong., 2d Sess. (1970); Foreign Bank Secrecy and Bank Records: Hearings on H.R. 15073 Before the House Comm, on Banking and Currency, 91st Cong., 1st & 2d Sess. (1969-70); Foreign Bank Secrecy: Hearings on S. 3678 & H.R. 15073 Before the Subcomm. on Financial Institutions of the Sen. Comm, on Banking and Currency, 91st Cong., 2d Sess. (1970).
Based on the language of the statute, the Supreme Court characterization of it, and its legislative history, we are compelled to hold that this question must be classified as investigative and that therefore the “exculpatory no” doctrine applies here. We are quick to assuage the government’s fears that this holding sanctions false answers to any tax return question. First, our holding covers only this question on a tax return as illuminated by the statute that permits it. We do not deal today with questions such as this on other government forms, questions that are administrative in nature and that are related to the computation of taxes, or questions with a different statutory basis. Further, this doctrine is only a creature of section 1001; the government may still prosecute fraudulent tax returns containing this question under the perjury statute of the IRC, 26 U.S.C. § 7206.
With these limitations on our holding, we believe it to be a correct application of the “exculpatory no” doctrine that will not hamper legitimate government functions.
C. Counts Six through Eleven.
Counts six through nine allege failures by the Hajecates to report transportation of currency on four dates in violation of 31 U.S.C. §§ 1059(1) and 1101. Counts ten and eleven deal with the Hajecates’ failure to make annual reports of a foreign bank account in violation of 31 U.S.C. §§ 1121 and 1059(1).
Before the government can prosecute under 31 U.S.C. § 1059, it must allege that the violation was committed in furtherance of the commission of another violation of federal law or committed as part of a pattern of illegal activity involving transactions exceeding a specified dollar amount. In counts six through eleven, the government alleges that the companion crimes necessary for a prosecution under section 1059 were violations of 18 U.S.C. §§ 371 and 1001. However, in none of these counts does the government provide the Hajecates with notice of the violations of federal law that they are accused of under sections 371 and 1001. While the implicit reference may be to the prior counts in the indictment, such an implicit reference does not satisfy the requirements of due process. Fed.R.Crim.P. 7(c) declares that allegations made in one count may be incorporated by reference in another count. But this court long ago held that while the specificity required in an indictment can be achieved by incorporation of another count, this incorporation must be express, not implicit. See Davis v. United States, 357 F.2d 438, 440 & n.2 (5th Cir.), cert. denied, 385 U.S. 927, 87 S.Ct. 284, 17 L.Ed.2d 210 (1966).
This simple oversight by the government — failure to incorporate a prior count expressly — renders counts six through eleven defective as to the section 1059 allegations. These counts simply do not provide sufficient notice to the defendants of the sections 1001 and 371 crimes [902]*902with which they are charged. See Van Liew, supra.
As to the sections 1101 and 1121 allegations in counts six through eleven, the record reveals that the defendants never made a Davis-based attack on them, and we do not pass on their sufficiency under Davis. In addition, we see no merit in the other defects the defendants have alleged. Therefore, counts six through eleven remain valid in part.
D. Conclusion.
To summarize, we uphold the dismissal of counts two through five in their entirety and the dismissal of portions of counts one and six through eleven by the district court but reverse the dismissal of (1) count one as to objects one, two, and four, and (2) portions of counts six through eleven.
III. THE HAJECATES’ CROSS-APPEAL.
The Hajecates cross appeal the denial by the district court of dismissal of the entire indictment based on prosecutorial vindictiveness. The factual basis of this claim is that in 1979 two grand juries in the Southern District of Texas returned 84- and 29-count indictments against the Hajecates and others. These indictments were dismissed by the district court, but their dismissal was reversed and remanded by this court on appeal in United States v. Uni Oil, Inc., 646 F.2d 946 (5th Cir. 1981). While the appeal from dismissal of these indictments was pending before this court, the government convened another grand jury and sought and obtained the indictment at issue here. The Hajecates immediately moved to dismiss the indictment, alleging that it was vindictive. The district court denied this motion, and the Hajecates took this appeal.
We need go no further than an examination of our jurisdiction to entertain this appeal in order to resolve this issue. The order from which the defendants Hajeeate appeal is an interlocutory order, and this court has recently ruled that an interlocutory appeal does not lie from the denial of a pretrial motion to dismiss for prosecutorial vindictiveness. United States v. Gregory, 656 F.2d 1132 (5th Cir. 1981). We are bound by Gregory and therefore have no jurisdiction to entertain this cross appeal by the Hajecates.
APPEAL AFFIRMED IN PART AND REVERSED IN PART AND REMANDED; CROSS-APPEAL DISMISSED.