PartnerFacts
Data last updated: Oct 23, 2026, 5:45 PM ETLatest filing: Oct 22, 2026Now: Oct 24, 2026, 5:04 AM ET

Sponsor Check › Person

MC
No photo found yet (own website and image search run after this page is viewed)

Mark Christopherson

Named as an officer, director or promoter on SEC Form D filings · MN · Sep 30, 2013 → Jan 22, 2026

3deals (issuers)
$32.8Mreported sold
41investors
3Form D filings
2013–2026years on file

Data last updated Oct 23, 2026, 5:45 PM ET · Courts (RECAP) last checked: Oct 24, 2026, 2:29 AM ET · SEC enforcement last checked: covered by the index scan as of Oct 24, 2026, 2:50 AM ET

The short version

Mark Christopherson is listed as an executive officer and director on 3 SEC Form D filings by 3 issuers between Sep 2013 and Jan 2026: NXTHERA INC (Maple Grove, MN — other health care — 2013; $25M reported sold to 31 investors), Lunair Medical, Inc. (Minneapolis, MN — other health care — 2025; $7.5M reported sold to 3 investors) and Bone Foam, Inc. (Corcoran, MN — other health care — 2026; $290K reported sold to 7 investors).

What this means A repeat sponsor — 3 separate companies raised money with this person listed as executive officer and director, over about 13 years. Across those companies the filings report $32.8M sold in total.

Listed alongside Andre de Bruin (1 shared filing), Carmen L. Bringgold (1 shared filing), David Neustaedter (1 shared filing), Glen Nelson (1 shared filing), Howard R. Levin (1 shared filing) and 10 others.

What this means These are the other officers, directors or promoters the companies named on the same forms — the team around Mark. Each name links to their own page.

1 of the issuers belongs to the sponsor group Nxthera (2 issuers, $60.6M reported sold, 2009–2024).

What this means A sponsor group is one team that sets up a new company for each deal. Nxthera has 2 companies on file and $60.6M reported sold in total — the group page shows the whole track record in one place.

Public records searched: federal courts (CourtListener / RECAP), SEC enforcement releases, state securities regulators (AZ, CA, DE, TX, WA) — 6 bankruptcy cases matching the name listed in Key records below.

What this means 6 records came back. Each one is listed below with a link to the original document and a line saying why it matched. A name match is not proof it is the same person or company — read the why line and the document. Being sued or named in a release is an accusation, not a finding.

We compared 3 public filings for Mark Christopherson and found 4 differences: Form D filed 20 days after the first sale; Form D filed 40 days after the first sale; and more below.

What this means These are differences between the sponsor's own SEC filings — both values, dates and sources are listed in Key records, section 4. Most have ordinary explanations; ask the sponsor.

What the community is saying

Community search for Mark Christopherson has not run yet — it is joining a line of 5,585 names; searches run around the clock at the hosts' allowed rate. Searched so far: 27 names.

Community comments are quoted as written by their authors. Sources searched: BiggerPockets forums (via DuckDuckGo, Brave, Bing and BiggerPockets search) and Reddit (search feed + public archive).

Key records

Five things investors ask first. Items still in human review are counted, not shown.

1. Lawsuits

None found in sources searched — federal courts (CourtListener / RECAP), checked Oct 24, 2026

What was searched

Sources searched: CourtListener bulk data (RECAP dockets as of 2026-09-30; recall-first rule 10-24) — federal district + bankruptcy courts State courts: not covered (one-tap state court links under Look further). PACER: not searched. · Last checked Oct 24, 2026, 2:29 AM ET.

State courts: not covered (one-tap state court links under Look further). No state offers a lawful automated statewide source PartnerFacts can use today. Texas (re:SearchTX) terms prohibit storing results in a database open to third parties; New York (WebCivil) and Massachusetts (MassCourts) require a browser check that blocks scripted queries; California has no statewide index (58 county portals; Rule of Court 2.503 grants name-based access case by case); Florida, Utah and Illinois offer paid or partial access whose terms for automated use are unverified. Washington (dw.courts.wa.gov; bulk index reports under a JISC data-dissemination agreement), Delaware (CourtConnect; Court of Chancery not included) and Arizona (apps.azcourts.gov/publicaccess, which has an official channel to request high-volume access) are the candidates; PartnerFacts will request written permission before any automated search. Federal courts are searched through CourtListener / RECAP.

2. Regulatory actions

None found in sources searched — SEC enforcement releases (index scan as of Oct 24, 2026, 2:50 AM ET) · state securities regulators: AZ, CA, DE, TX, WA (crawled Oct 23, 2026)

What was searched

SEC enforcement searched: SEC litigation releases and administrative proceedings — respondent names in the sec.gov index titles (30,205 releases, 1995-09-19 to 2026-10-23); release text is read only to confirm a candidate. Names that appear only in the body of a release are not found. — Searched SEC litigation releases and administrative proceedings (1995→ / 2007→) (30,205 records as of Oct 24, 2026, 2:50 AM ET) — nothing matched Mark Christopherson..

State securities regulators searched: AZ (Corporation Commission Securities Division), CA (DFPI — 16 of 12,159 DFPI respondent pages read so far; sponsor-name matches are read first), DE (DOJ Investor Protection Unit), TX (State Securities Board), WA (DFI) — last crawled Oct 23, 2026, 9:57 PM ET. Other states are not covered.

3. Bankruptcies

6 cases: 6 closed (disposition not in docket feed)

Mark R. Christopherson and Karrie K. Christopherson closed
United States Bankruptcy Court, D. Minnesota · No. 10-35539 · Filed Jul 29, 2010 · Closed Apr 22, 2011
Role of Mark R. Christopherson and Karrie K. Christopherson: Debtor · Outcome: Case closed 2011-04-22 (disposition not included in the bulk docket feed — see docket) Docket on CourtListener ↗
same full name (a name found in 9 federal dockets); court in the person's filing state (MN)
Mark S Christopherson and Terri R Christopherson closed
United States Bankruptcy Court, N.D. Iowa · No. 09-02766 · Filed Sep 22, 2009 · Closed Nov 1, 2011
Role of Mark S Christopherson and Terri R Christopherson: Debtor · Outcome: Case closed 2011-11-01 (disposition not included in the bulk docket feed — see docket) Docket on CourtListener ↗
same full name (a name found in 9 federal dockets); court in IA (not a filing state)
Mark T. Christopherson and Tammy J. Christopherson closed
United States Bankruptcy Court, E.D. Virginia · No. 03-40351 · Filed Oct 31, 2003 · Closed Feb 17, 2004
Role of Mark T. Christopherson and Tammy J. Christopherson: Debtor · Outcome: Case closed 2004-02-17 (disposition not included in the bulk docket feed — see docket) Docket on CourtListener ↗
same full name (a name found in 9 federal dockets); court in VA (not a filing state)
Mark R Christopherson closed
United States Bankruptcy Court, D. Idaho · No. 00-00641 · Filed Mar 17, 2000 · Closed Apr 27, 2001
Role of Mark R Christopherson: Debtor · Outcome: Case closed 2001-04-27 (disposition not included in the bulk docket feed — see docket) Docket on CourtListener ↗
same full name (a name found in 9 federal dockets); court in ID (not a filing state)
Mark R. Christopherson closed
United States Bankruptcy Court, E.D. California · No. 99-30530 · Filed Aug 6, 1999 · Closed Dec 15, 1999
Role of Mark R. Christopherson: Debtor · Outcome: Case closed 1999-12-15 (disposition not included in the bulk docket feed — see docket) Docket on CourtListener ↗
same full name (a name found in 9 federal dockets); court in CA (not a filing state)
Mark Christopherson closed
United States Bankruptcy Court, N.D. Illinois · No. 90-06232 · Filed Apr 4, 1990 · Closed Sep 14, 1990
Role of Mark Christopherson: Debtor · Outcome: Case closed 1990-09-14 (disposition not included in the bulk docket feed — see docket) Docket on CourtListener ↗
same full name (a name found in 9 federal dockets); court in IL (not a filing state)
What was searched

Sources searched: Federal bankruptcy courts via CourtListener / RECAP archive (federal district courts, federal bankruptcy courts). State courts: not covered (one-tap state court links under Look further). PACER: not searched (RECAP only). · Last checked Oct 24, 2026, 2:29 AM ET.

Court records show docket facts only; we never restate allegations as facts. Outcome wording comes from the docket feed; where it does not state a disposition we say so.

State courts: not covered (one-tap state court links under Look further). No state offers a lawful automated statewide source PartnerFacts can use today. Texas (re:SearchTX) terms prohibit storing results in a database open to third parties; New York (WebCivil) and Massachusetts (MassCourts) require a browser check that blocks scripted queries; California has no statewide index (58 county portals; Rule of Court 2.503 grants name-based access case by case); Florida, Utah and Illinois offer paid or partial access whose terms for automated use are unverified. Washington (dw.courts.wa.gov; bulk index reports under a JISC data-dissemination agreement), Delaware (CourtConnect; Court of Chancery not included) and Arizona (apps.azcourts.gov/publicaccess, which has an official channel to request high-volume access) are the candidates; PartnerFacts will request written permission before any automated search. Federal courts are searched through CourtListener / RECAP.

4. Differences between public sources

Comparisons cover issuers and sponsor groups — see the issuer pages under Deals

4 differences found between the filings for Mark Christopherson (compared 3 filings on Oct 24, 2026)

Note · Jan 2, 2026 – Jan 22, 2026

Form D filed 20 days after the first sale — Bone Foam, Inc.

The filing says the first sale was Jan 2, 2026. The Form D was filed Jan 22, 2026 — 20 days later. The rule: a Form D is generally due within 15 days after the first sale, so this one is 5 days past that.

What this means A late notice is common and carries no penalty by itself. It is worth asking the sponsor why the paperwork lagged.

Sources
Note · Aug 6, 2025 – Sep 15, 2025

Form D filed 40 days after the first sale — Lunair Medical, Inc.

The filing says the first sale was Aug 6, 2025. The Form D was filed Sep 15, 2025 — 40 days later. The rule: a Form D is generally due within 15 days after the first sale, so this one is 25 days past that.

What this means A late notice is common and carries no penalty by itself. It is worth asking the sponsor why the paperwork lagged.

Sources
Note · Aug 6, 2025 – Sep 15, 2025

No amendment in the last 12 months on an offering that may still be open — Lunair Medical, Inc. (latest filing Sep 15, 2025)

The latest filing for this offering is dated Sep 15, 2025 (first sale Aug 6, 2025). It reports $7,500,000 sold of $12,500,000 offered. No later amendment is in our index as of Oct 24, 2026.

What this means SEC rules expect a yearly amendment while an offering is still going. The raise may simply have ended — a Form D does not say when it closed. Ask the sponsor whether the offering closed, when, and at what amount.

Sources
Note · Sep 24, 2013 – Sep 30, 2013

No amendment in the last 12 months on an offering that may still be open — NXTHERA INC (latest filing Sep 30, 2013)

The latest filing for this offering is dated Sep 30, 2013 (first sale Sep 24, 2013). It reports $6,575,000 sold of $13,200,000 offered. No later amendment is in our index as of Oct 24, 2026.

What this means SEC rules expect a yearly amendment while an offering is still going. The raise may simply have ended — a Form D does not say when it closed. Ask the sponsor whether the offering closed, when, and at what amount.

Sources
What is compared

What is compared: every Form D and D/A we hold for this subject, side by side — filing dates vs. first-sale dates (the 15-day rule), amendment timing on open offerings (the yearly-amendment expectation), amounts sold, investor counts, offering amounts and minimums across amendments, industry and size bands, addresses, how each person's name and role is written, paid sellers' CRD numbers, and (for groups) where the member companies were formed and sit. Everything is as filed by the issuer; the SEC does not check it. Differences are common and usually have ordinary explanations — we show both values, the dates, and the source so you can ask. As of Oct 24, 2026.

5. Money to insiders

None reported on 3 offerings — no sales commissions, finder's fees or proceeds to insiders

Per-offering detail
Offering (latest filing)Sales commissionsFinder's feesTo insidersPaid to sell itSource
Jan 22, 2026 D
Bone Foam, Inc.
File 021-570680
$0$0$0None listed on this filingEDGAR ↗
Sep 15, 2025 D
Lunair Medical, Inc.
File 021-557549
$0$0$0 (est.)
Excludes standard compensation for officers and directors.
None listed on this filingEDGAR ↗
Sep 30, 2013 D
NXTHERA INC
File 021-203707
$0$0$0None listed on this filingEDGAR ↗

Counts come from Form D Items 12–15 on the filings in our index (latest filing per offering; one offering = one SEC file number; an amendment updates its offering rather than adding one). "To insiders" = gross proceeds used for payments to executive officers, directors or promoters. "—" = not reported on that filing. Amounts marked (est.) were reported as estimates. "Paid to sell it" = sales compensation recipients named on that filing (Item 12), each linked to FINRA BrokerCheck when a CRD number is reported.

Counted across every filing this person is listed on (latest filing per offering, per issuer).

Deals 3

Every issuer that named Mark Christopherson on a Form D, newest first. A Form D is the notice a company files after it starts selling a private investment.

Other Health Care

Bone Foam, Inc.

Corcoran, MN · Jan 22, 2026
  • Jan 22, 2026 · D · $290,003 sold of $350,000 · 7 investors · min. $20,000 · role: Director EDGAR ↗

Raised $290K from 7 investors (83% of the $350K target) as of the latest filing. Mark is listed as director.

Sources

Every row is a Form D or D/A on which the issuer listed this name as a related person. Amount sold and investors are the maximum reported on any filing for this issuer.

Other Health Care

Lunair Medical, Inc.

Minneapolis, MN · Sep 15, 2025
  • Sep 15, 2025 · D · $7,500,000 sold of $12,500,000 · 3 investors · min. No minimum reported · role: Executive Officer, Director EDGAR ↗

Raised $7.5M from 3 investors (60% of the $12.5M target) as of the latest filing. Mark is listed as executive officer, director.

Sources

Every row is a Form D or D/A on which the issuer listed this name as a related person. Amount sold and investors are the maximum reported on any filing for this issuer. "Similar" = offerings in the same industry claiming the same exemption, filed in the last 5 years: Other Health Care / 506(b) (4,189 filings); ranges are the middle half (25th–75th percentile). Computed by PartnerFacts from SEC EDGAR Form D data as of Oct 23, 2026, 5:45 PM ET. Rows without a range: fewer than 30 comparable filings, or not a Rule 506 offering. No ranking or score.

Other · group: Nxthera

NXTHERA INC

Maple Grove, MN · Sep 30, 2013
  • Sep 30, 2013 · D · $6,575,000 sold of $13,200,000 · 20 investors · min. No minimum reported · role: Executive Officer EDGAR ↗

Raised $25M from 31 investors (100% of the $13.2M target) as of the latest filing. Mark is listed as executive officer.

Sources

Every row is a Form D or D/A on which the issuer listed this name as a related person. Amount sold and investors are the maximum reported on any filing for this issuer. "Similar" = offerings in the same industry claiming the same exemption, filed in the last 5 years: Other / 506(b) (18,678 filings); ranges are the middle half (25th–75th percentile). Computed by PartnerFacts from SEC EDGAR Form D data as of Oct 23, 2026, 5:45 PM ET. Rows without a range: fewer than 30 comparable filings, or not a Rule 506 offering. No ranking or score.

People around Mark 15

Officers, directors, promoters and management entities named on the same filings, as of Oct 23, 2026, 5:45 PM ET.

JP
No photo found yet (own website and image search run after this page is viewed)
Person

J. Robert Paulson

Executive Officer, Director · 1 shared filing (1 issuer) · also on 4 other issuers

J. Robert Paulson is on 5 issuers in total — a repeat sponsor. Their page lists every one.

SH
No photo found yet (own website and image search run after this page is viewed)
Person

Sami Hamade

Director · 1 shared filing (1 issuer) · also on 8 other issuers

Sami Hamade is on 9 issuers in total — a repeat sponsor. Their page lists every one.

MH
No photo found yet (own website and image search run after this page is viewed)
Person

Michael Hoey

Executive Officer, Director · 1 shared filing (1 issuer) · also on 3 other issuers

Listed on the same filings as Mark Christopherson. Their page shows their other deals.

JG
No photo found yet (own website and image search run after this page is viewed)
Person

Jan Garfinkle

Director · 1 shared filing (1 issuer) · also on 14 other issuers

Jan Garfinkle is on 15 issuers in total — a repeat sponsor. Their page lists every one.

AB
No photo found yet (own website and image search run after this page is viewed)
Person

Andre de Bruin

Director · 1 shared filing (1 issuer) · also on 1 other issuer

Listed on the same filings as Mark Christopherson. Their page shows their other deals.

PL
No photo found yet (own website and image search run after this page is viewed)
Person

Paul LaViolette

Director · 1 shared filing (1 issuer) · also on 19 other issuers

Paul LaViolette is on 20 issuers in total — a repeat sponsor. Their page lists every one.

DN
No photo found yet (own website and image search run after this page is viewed)
Person

David Neustaedter

Director · 1 shared filing (1 issuer) · also on 9 other issuers

David Neustaedter is on 10 issuers in total — a repeat sponsor. Their page lists every one.

CB
No photo found yet (own website and image search run after this page is viewed)
Person

Carmen L. Bringgold

Executive Officer · 1 shared filing (1 issuer)

Listed on the same filings as Mark Christopherson. Their page shows their other deals.

HL
No photo found yet (own website and image search run after this page is viewed)
Person

Howard R. Levin

Director · 1 shared filing (1 issuer) · also on 1 other issuer

Listed on the same filings as Mark Christopherson. Their page shows their other deals.

TL
No photo found yet (own website and image search run after this page is viewed)
Person

Tom Lowe

Director · 1 shared filing (1 issuer)

Listed on the same filings as Mark Christopherson. Their page shows their other deals.

MH
No photo found yet (own website and image search run after this page is viewed)
Person

Michael Hurley

Director · 1 shared filing (1 issuer) · also on 3 other issuers

Listed on the same filings as Mark Christopherson. Their page shows their other deals.

RK
No photo found yet (own website and image search run after this page is viewed)
Person

Robert Korljan

Director · 1 shared filing (1 issuer)

Listed on the same filings as Mark Christopherson. Their page shows their other deals.

JP
No photo found yet (own website and image search run after this page is viewed)
Person

John Peterson

Director · 1 shared filing (1 issuer)

Listed on the same filings as Mark Christopherson. Their page shows their other deals.

PC
No photo found yet (own website and image search run after this page is viewed)
Person

Peter Alexander Cole

Director · 1 shared filing (1 issuer)

Listed on the same filings as Mark Christopherson. Their page shows their other deals.

GN
No photo found yet (own website and image search run after this page is viewed)
Person

Glen Nelson

Director · 1 shared filing (1 issuer) · also on 5 other issuers

Glen Nelson is on 6 issuers in total — a repeat sponsor. Their page lists every one.

The team behind the deals

Sponsor group

Nxthera

2 issuers · 18 filings · $60.6M reported sold · 2009–2024

One team, 2 deal companies. Mark Christopherson is listed on 1 of them.

Sources

Issuers are grouped when their Form D filings share related persons, a management entity or a business address (automatic match from the filings). "Listed" marks the issuers that name Mark Christopherson.

Same business address

2 other issuers file from the same address

A shared address can mean the same team, a shared office building or a registered agent. It is a lead, not a conclusion.

Registrations and other filings

Adviser registration (Form ADV)

None of the 3 issuers this person is listed on appears in Form ADV (searched 24,962 advisers as of Oct 2, 2026). A person is never an adviser firm; Form ADV is checked for the issuers and the management companies they are listed with.

Other offering types (Regulation A and Regulation Crowdfunding)

Searched SEC Regulation A Data Sets (Forms 1-A, 1-K, 1-Z; 2015 Q2 → 2026 Q3); SEC Crowdfunding Offerings Data Sets (Form C family; 2016 Q2 → 2026 Q3); EDGAR form index for 2026 Q3 → 2026 Q4 (51,358 records as of Oct 23, 2026, 8:41 PM ET) — nothing matched this name.

Property records none — individuals are not matched

Property records are matched to companies only, never to individuals, so none are matched to Mark Christopherson by design. Searched property records in Hillsborough County FL (Clerk recorded-document index Oct 14, 2026 to Oct 15, 2026 + FL DOR 2026 ownership roll), Miami-Dade County FL (FL DOR 2026 ownership roll), Harris County TX (HCAD 2026 ownership roll), Dallas County TX (DCAD 2026 ownership roll), New York City ACRIS documents and PLUTO ownership rows already retrieved for other issuers, Cook County IL sale and ownership rows already retrieved for other issuers (814,874 records as of Oct 23, 2026, 8:59 PM ET) for the 3 issuers this person is listed on — nothing matched.

Public profiles and social

Websites and social links of the issuers Mark Christopherson is listed on: none on file. No website or social profile named in Lunair Medical, Inc.'s SEC filings (Form C, Reg A, Form ADV; checked Oct 24, 2026). Web search for this name: #61,298 of 374,652 in line (14 issuers searched so far). One-tap searches: Look further ↓

Look further

One-tap searches on sites we do not index ourselves, with the name pre-filled (Minneapolis, MN). Each opens in a new tab; what you find there is not verified by PartnerFacts.

Change history

No corrections have been requested for this page.

Every fact links to its public-record source. Plain-English notes next to a fact are our reading of that fact, not a rating. Request a correction · Facts policy

Request a correction

Free. Logged with status: received → under review → fixed / confirmed with source.

Add a response

If this is you or your firm, add a sourced explanation next to any fact. Reviewed before publishing.

Monitor this person

Members get an email when Mark Christopherson appears on a new Form D, or when a court case or SEC action is matched to them. See plans →