Section 16 of the SF-86 asks for three people who know you well. What the written-inquiry stage sends them is a two-page form, mailed from a post office box in Boyers, Pennsylvania, with nine numbered items on the back and a return envelope inside. The government estimates it takes 5 minutes.

The form is INV Form 42, “Investigative Request for Personal Information,” issued by the Defense Counterintelligence and Security Agency. The current version is revision 10/21, approved under OMB control number 0705-0003 through October 2027. It is public, so the list below is the actual text, not a reconstruction.

What does Section 16 actually require?

Short answer: Three people who know you well, whose combined association covers at least the last seven years. Not your spouse, a former spouse, other relatives, or anyone named elsewhere on the form.

The SF-86 asks for “three people who know you well and who preferably live in the U.S. … who are collectively aware of your activities outside of your workplace, school, or neighborhood, and whose combined association with you covers at least the last seven (7) years.”

The load-bearing word is combined, and it means covered, not added up. The three acquaintance periods have to span the last seven years between them. Three people you each met two years ago give you six years of acquaintance but cover only two, leaving years three through seven blank. A friend from nine years back plus a running partner from last spring do cover it.

The exclusion clause is stricter than most expect. Section 16 bars “your spouse, former spouse(s), other relatives, or anyone listed elsewhere on this form,” so a supervisor named in your employment history cannot be recycled here. Our breakdown of whether you can list a relative as a reference or verifier covers the edge cases.

Section 11 runs on a different clock: ten years of residence history, but a verifier only for addresses in the last three years. If you are stuck there, see what to do about a forgotten address verifier.

What do your references actually receive?

Short answer: Quite possibly nothing. The INV series goes to contacts named on your questionnaire “through an automated mailing operation,” but on DCSA’s own volumes most listed associates are never mailed one, and 5 CFR 736.102(a) treats contact “in person or by telephone” as an ordinary channel too.

OPM’s 2018 Federal Register notice is plain about the mechanics: the INV 40 through 44 conduct the “written inquiries” portion of an investigation, driven off the SF-85, SF-85P or SF-86. The agency running it is now DCSA, not OPM; if the acronym is new, we have a primer on what DCSA actually does.

How many of your three names get one is another question. DCSA’s approved estimate is 57,285 INV 42 responses a year across the whole federal government, against 2,022,183 employment inquiries. Every applicant lists exactly three associates and a variable number of employers, so if every listed name were mailed a form the associate column would be the larger one. It is not. Our inference from those two published figures: most people you name never receive an INV 42. What would falsify it is a per-case mailing rate, which DCSA does not publish.

The front panel carries a field headed “THIS PERSON CLAIMED THE FOLLOWING,” plus a certification that your written consent is on file and can be produced on request if your reference suspects the letter is a scam.

What are the nine questions on the INV 42?

Short answer: Four calibration questions about the relationship, one accuracy check against what you claimed, two on honesty and adverse information, one open field, and one recommendation.

1. How long have you known this person? Years and months, or a box marked “I don’t know this person,” which ends the form.
2. My association with this person is/was as a: coworker, neighbor, friend, spouse, former spouse, instructor, relative, other.
3. On the average, I associate(d) with this person: daily, weekly, monthly, twice a year, once every year or 2, once in 3 or more years.
4. I last associated with this person: 0 to 3 months ago, 3 to 12 months ago, 1 to 3 years ago, 3 to 5 years ago, more than 5 years ago.
5. Does the information on the front of this form concerning this person appear to be correct? Yes, or no with corrected data in item 8.
6. Do you have any reason to question this person’s honesty or trustworthiness? No; yes with explanation; “I do not know this person well enough to respond”; or “I wish to discuss the adverse information I have.”
7. Do you have any adverse information about this person’s employment, residence or activities concerning: violations of the law, finances, abuse of alcohol, abuse or illegal use of drugs, mental or emotional stability, general behavior or conduct, other matters.
8. Additional information which you feel may have a bearing on this person’s eligibility. The form says this space may carry derogatory as well as positive information, a confidentiality request, or a request for a copy of the consent.
9. Do you recommend this person for eligibility for employment or security clearance? Yes; no with explanation; or “I don’t know this person well enough to make a recommendation.”

Nothing in items 1, 3 and 4 concerns your character. They establish whether the person answering items 6 through 9 is in a position to know.

How does the associate form differ from the employment form?

Short answer: They share the honesty question, the seven-category adverse grid and the recommendation. Only the employment form asks why you left and about rehire eligibility. Only the associate form asks how well you actually know each other.

The employment form is harsher by a distance. Item 2 is an unranked pick-one list of eight, from “subject currently employed here” through “fired” to “left by mutual agreement following notice of unsatisfactory performance.” Item 3 asks about rehire eligibility and separates blanket company policy from “reasons relating to unfavorable employment.” Your friend is asked how often you see each other.

Can a reference answer anonymously?

Short answer: Not by default, and there are two routes to a pledge, not one. The source can request it; the agent can also offer it unprompted. What 5 CFR 736.102 forbids is the source assuming a pledge, and the agent suggesting the source ask for one.

Paragraph (b) runs four sentences and most write-ups print three. An agent may grant a pledge “upon specific request by the source.” The sentence that goes missing comes next: “In addition, the agent has discretion to offer the source a pledge of confidentiality where the agent believes that such a pledge is necessary to obtain information pertinent to the investigation.” Only then the two limits: “a pledge of confidentiality may not be assumed by the source,” and “the interviewing agent may not suggest to a source that the source request confidentiality.” An agent cannot coach a source into asking, but may offer unprompted, exactly where a source is sitting on adverse information. Paragraph (d) is the other omitted half: a pledge “extends only to the identity of the source, and to any information furnished by the source that would reveal the identity of the source.” It covers who said it, not what was said. The substance still reaches your file.

On the form, a reference holding information they feel unable to furnish without such a promise is told to say so in writing on the reverse “and provide only your contact information,” because “providing additional information on this form will void your request for confidentiality.” A 2018 notice announced that sentence was being removed; the Rev. 10/21 form still carries it. The form then contradicts itself: item 8 invites the reference to use that space “to provide derogatory as well as positive information, to request confidentiality, and/or to request a copy of the consent.” A source who wants both to explain something and to stay unnamed should call the case number on the form rather than trust either sentence.

How much do three names really matter?

Short answer: Less than the anxiety around them suggests. On DCSA’s current per-form breakdown, personal-associate inquiries are 2.0% of written-inquiry volume: a human cross-check bolted onto a much larger records process.

The currently approved collection publishes the split form by form, and it is worth printing even though it cuts against this article’s own premise. Of 2,850,071 annual responses across the five INV forms, 2,022,183 are employment inquiries and 57,285 are personal-associate inquiries: about 35 employer forms for every friend form. The per-form entries report respondents and annual responses as the same number here, one response per respondent.

The gap used to be wider: OPM’s January 2018 estimate, before the collection moved to the Defense Department, ran close to 60 to 1. Different agency, different years, so read the pair as a trend, not a series.

What survives is the shape. The machine points overwhelmingly at employers and records; your three names cross-check that rather than drive it. A lukewarm answer to item 9 is one input into a whole-person judgment, not a verdict.

What should you tell each reference in advance?

Short answer: One sentence, sent once, telling them the government may contact them, who it would be from, and that answering honestly from memory is the whole job. Anything beyond that starts to look like coordinating a story.

Here is the sentence: “I listed you as one of three references on my SF-86 security clearance questionnaire; you may hear nothing, or you may get a short form in the mail from DCSA in Boyers, Pennsylvania, or a call or a visit from a federal investigator, asking how long we have known each other and how often we are in touch. Answer exactly as you remember it.”

Do not promise them mail. On the volumes above that promise is wrong more often than it is right, and a reference primed to expect an envelope is the one most likely to hang up on a real investigator. The sentence is not coaching; it gives them a fair shot at item 5.

The boundary is that same item 5, read next to the certification you signed under 18 U.S.C. 1001. Telling someone they may be contacted is preparation; telling them what to say is a different act, and item 5 exists to surface the mismatch. None of this is legal advice; a difficult disclosure is a conversation for a clearance attorney.

What is not published?

Short answer: The nine items are the written inquiry, not the entire universe. Some investigations also involve a spoken contact with a source, and no federal source publishes what gets asked in one.

5 CFR 736.102(a) specifies only what the investigator must disclose in a spoken contact: the purpose, the uses of the information, and the fact that the source’s identity may be released to you. It never specifies what the investigator must ask, and the governing document is not public: the Personnel Vetting Policy Index still lists the “Federal Personnel Vetting Investigative Standards and Appendices” as “(To be posted soon).” Any article handing you a script for a spoken reference interview built it out of nothing. Nor is the timing published: no federal source says how many days after submission a reference hears anything, so any figure quoted for that is invented. Many applicants work through the wait on an interim clearance.

Everything above describes the SF-86 as revised November 2016, still operative, but the Personnel Vetting Questionnaire has begun replacing it, with the first PVQ forms collected in FY2026-Q2 and full adoption targeted for September 2027. Nothing is published about what the PVQ’s equivalent of Section 16 will ask. Legacy periodic reinvestigations have meanwhile given way to continuous vetting.

Frequently Asked Questions

Will my references know I named them?

Yes. The INV 42 states that “your contact information was provided by the person identified below,” and the front of the form identifies you by name. It also shows them what you claimed and asks in item 5 whether it appears correct.

Can I list someone who has known me only two years?

Yes, provided your three references collectively cover at least seven years. The SF-86 asks for people “whose combined association with you covers at least the last seven (7) years.” Covers, not sums: no individual has to span the full period, but between them the three acquaintance periods must reach back seven years.

What happens if a reference ignores the form?

The form calls disclosure voluntary, then names the cost: failure to provide the information “may result in our agency’s inability to conduct a thorough investigation and may prevent the government from making a determination or adjudication …” An unanswered form is nobody’s violation, and not a neutral event either.

Can I find out what my references wrote?

The Privacy Act statement promises the information, “including your identity, will be furnished … to the person investigated upon his or her specific request.” Read the routine-uses clause on the same panel before budgeting on it: “Information obtained will also be released to the person being investigated upon their request unless otherwise exempt.” The form does not say which exemptions apply; they are asserted in the record system it names, “DUSDI 02-DoD.” A granted pledge protects the source’s identity, not the substance, and adverse information that threatens eligibility usually surfaces through a Statement of Reasons instead.

Do these forms apply only to security clearances?

No. The 2018 notice describes the INV series as driven off the SF-85 and SF-85P as well as the SF-86, so the same inquiries run for suitability and public trust investigations.

The practical conclusion

Pick people who can answer items 1, 3 and 4 without hedging: long acquaintance, regular contact, recent contact. That choice does more work than any conversation afterward, and it is available only while Section 16 is blank. Send the one sentence, then leave it alone. By September 2027, when the PVQ is scheduled to have replaced the SF-86, the section number will have changed. The underlying test almost certainly will not: the government is checking whether the people who vouch for you are in any position to know.

Primary sources: SF-86 (OPM, revised November 2016); INV Form 42 (Rev. 10/21), DCSA; OMB collection 0705-0003 and its per-form INV 42 estimate; 83 FR 3370; 5 CFR 736.102; Trusted Workforce 2.0 QPR, FY2025-Q4/FY2026-Q1; Personnel Vetting Policy Index.