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Data last updated: Oct 23, 2026, 5:45 PM ETLatest filing: Oct 22, 2026Now: Oct 24, 2026, 7:43 AM ET

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William Siegenthaler

Named as an officer, director or promoter on SEC Form D filings · PA · Oct 20, 2008 → Oct 20, 2008

2deals (issuers)
$0reported sold
0investors
2Form D filings
2008year on file

Data last updated Oct 23, 2026, 5:45 PM ET · Courts (RECAP) last checked: Oct 24, 2026, 2:17 AM ET · SEC enforcement last checked: covered by the index scan as of Oct 24, 2026, 2:50 AM ET

The short version

William Siegenthaler is listed as an executive officer on 2 SEC Form D filings by 2 issuers in Oct 2008: CMS 2008 Investment Partners PE, L.P. (Wynnewood, PA — investing — 2008) and CMS 2008 Investment Partners PE-Q, L.P. (Wynnewood, PA — investing — 2008).

What this means 2 separate companies raised money with this person listed as executive officer. Across those companies the filings report $0 sold in total.

Listed alongside Ingrid R. Welch (2 shared filings), Mark I Solomon (2 shared filings), Paul Silberberg (2 shared filings), Richard A. Mitchell (2 shared filings) and William A. Landman (2 shared filings).

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

All 2 issuers belong to the sponsor group Merion (49 issuers, $411.5M reported sold, 2008–2026).

What this means A sponsor group is one team that sets up a new company for each deal. Merion has 49 companies on file and $411.5M 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 (AK, AL, AR, AZ, CA, CT, DE, FINRA, GA, HI, ID, IL, KS, KY, LA, MA, MD, ME, MI, MO, MS, MT, NASAA, NC, ND, NH, NM, NV, OK, OR, PA, RI, SC, SD, TN, TX, VT, WA, WI, WV, WY) — 3 court cases matching the name, 5 bankruptcy cases matching the name listed in Key records below.

What this means 8 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 2 public filings for William Siegenthaler and found 3 differences, 1 worth asking the sponsor about: Bankruptcy case: William T. Siegenthaler; 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 William Siegenthaler has not run yet — it is joining a line of 26,386 names; searches run around the clock at the hosts' allowed rate. Searched so far: 638 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

3 cases: 1 dismissed, 2 closed (disposition not in docket feed)

SIEGENTHALER v. CONSOLIDATED RAIL CO dismissed
District Court, E.D. Pennsylvania · No. 2:98-cv-04499 · Filed Aug 21, 1998 · Closed Nov 30, 1998 · Nature of suit: 330 Federal employers' liability
Role of SIEGENTHALER: Plaintiff · Outcome: Terminated 1998-11-30 — FJC Integrated Database disposition: Voluntarily dismissed Docket on CourtListener ↗
same rare surname (2 people in Form D filings, 14 federal dockets); surname only in the caption; court in the person's filing state (PA)
SIEGENTHALER v. TRUST CORP INC closed
District Court, N.D. Ohio · No. · Filed May 5, 1989 · Closed Jul 24, 1989 · Nature of suit: 850 Securities, Commodities, Exchange
Role of SIEGENTHALER: Plaintiff · Outcome: Terminated 1989-07-24 — FJC Integrated Database disposition: Statistical closing Docket on CourtListener ↗
same rare surname (2 people in Form D filings, 14 federal dockets); surname only in the caption; court in OH (not a filing state)
SIEGENTHALER D v. TRUSTCORP INC closed
District Court, N.D. Ohio · No. · Filed Feb 28, 1989 · Closed Apr 18, 1989 · Nature of suit: 850 Securities, Commodities, Exchange
Role of SIEGENTHALER D: Plaintiff · Outcome: Terminated 1989-04-18 — FJC Integrated Database disposition: Statistical closing Docket on CourtListener ↗
same rare surname (2 people in Form D filings, 14 federal dockets); surname only in the caption; court in OH (not a filing state)
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, 2:17 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.

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: VA (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 William Siegenthaler..

State securities regulators: Securities regulators searched (3,318 actions): AZ Corporation Commission Securities Division (411 actions, 2017–2026), CA DFPI (25 actions, 2007–2024; listing starts 2002 — 16 of 12,159 DFPI respondent pages read so far; sponsor-name matches are read first), DE DOJ Investor Protection Unit (257 actions, 1987–2026), TX State Securities Board (586 actions, 2006–2026), WA DFI (2,039 actions, 2001–2026) — last crawled Oct 23, 2026, 9:57 PM ET. No machine-readable public listing today for CO, FL, IA, IN, MN, NE, NJ, NY, OH, UT, VA (see docs/state-regulators.md).

3. Bankruptcies

5 cases: 5 closed (disposition not in docket feed)

Treinish v. R.J. Siegenthaler, D.C., INC closed
United States Bankruptcy Court, N.D. Ohio · No. 02-01031 · Filed Jan 24, 2002 · Closed Feb 10, 2003
Role of R.J. Siegenthaler, D.C., INC: Defendant · Outcome: Case closed 2003-02-10 (disposition not included in the bulk docket feed — see docket) Docket on CourtListener ↗
same rare surname (2 people in Form D filings, 14 federal dockets); different first name (d); court in OH (not a filing state)
John Siegenthaler closed
United States Bankruptcy Court, E.D. New York · No. 1-01-18520 · Filed Jun 25, 2001 · Closed Sep 23, 2002
Role of John Siegenthaler: Debtor · Outcome: Case closed 2002-09-23 (disposition not included in the bulk docket feed — see docket) Docket on CourtListener ↗
same rare surname (2 people in Form D filings, 14 federal dockets); different first name (john); court in NY (not a filing state)
John Siegenthaler closed
United States Bankruptcy Court, E.D. New York · No. 1-00-13640 · Filed Apr 5, 2000 · Closed Aug 10, 2001
Role of John Siegenthaler: Debtor · Outcome: Case closed 2001-08-10 (disposition not included in the bulk docket feed — see docket) Docket on CourtListener ↗
same rare surname (2 people in Form D filings, 14 federal dockets); different first name (john); court in NY (not a filing state)
William T. Siegenthaler closed
United States Bankruptcy Court, W.D. New York · No. 2-97-22478 · Filed Jun 30, 1997 · Closed Feb 24, 2000
Role of William T. Siegenthaler: Debtor · Outcome: Case closed 2000-02-24 (disposition not included in the bulk docket feed — see docket) Docket on CourtListener ↗
same rare surname (2 people in Form D filings, 14 federal dockets); first name matches; court in NY (not a filing state)
John Karl Siegenthaler closed
United States Bankruptcy Court, E.D. North Carolina · No. 92-01037 · Filed Apr 2, 1992 · Closed Jul 8, 1992
Role of John Karl Siegenthaler: Debtor · Outcome: Case closed 1992-07-08 (disposition not included in the bulk docket feed — see docket) Docket on CourtListener ↗
same rare surname (2 people in Form D filings, 14 federal dockets); different first name (karl); court in NC (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, 2:17 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

3 differences found between the filings for William Siegenthaler — 1 worth asking about (compared 2 filings on Oct 24, 2026)

Worth asking · Jun 30, 1997 – Feb 24, 2000

Bankruptcy case: William T. Siegenthaler — filed Jun 30, 1997

United States Bankruptcy Court, W.D. New York docket "William T. Siegenthaler" filed Jun 30, 1997, closed Feb 24, 2000. William Siegenthaler is listed as Debtor ("William T. Siegenthaler"). Our match estimate: 50%.

What this means A bankruptcy filing was found. Many are old or personal and have nothing to do with the deal — but ask what it was and when it closed.

Sources
Note · Feb 28, 1989 – Aug 21, 1998

3 court cases name William Siegenthaler

By role: plaintiff in 3. Newest: "SIEGENTHALER v. CONSOLIDATED RAIL CO" (District Court, E.D. Pennsylvania, Aug 21, 1998); "SIEGENTHALER v. TRUST CORP INC" (District Court, N.D. Ohio, May 5, 1989); "SIEGENTHALER D v. TRUSTCORP INC" (District Court, N.D. Ohio, Feb 28, 1989). Some of these are name matches with a match estimate below 95% — check each docket.

What this means Several court cases name this subject. Some are routine business suits. Ask what each was about and how it ended.

Sources
Note · Oct 20, 2008

William Siegenthaler appears on 2 deals that stopped filing before reaching their target

CMS 2008 Investment Partners PE, L.P. (last filing Oct 20, 2008; $0 sold of $500,000); CMS 2008 Investment Partners PE-Q, L.P. (last filing Oct 20, 2008; $0 sold of $500,000). Each has no filing in more than two years and reported under half its target sold.

What this means An issuer whose last filing is more than two years old and reported under half its target sold. The raise may have closed early or quietly stopped. Ask what happened to each.

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 2 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
Oct 20, 2008 D
CMS 2008 Investment Partners PE, L.P.
File 021-123555
$0$0$0None listed on this filingEDGAR ↗
Oct 20, 2008 D
CMS 2008 Investment Partners PE-Q, L.P.
File 021-123545
$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 2

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

Investing · group: Merion

CMS 2008 Investment Partners PE, L.P.

Wynnewood, PA · Oct 20, 2008
  • Oct 20, 2008 · D · $0 sold of $500,000 · 0 investors · min. $2,500 · role: Executive Officer (of MSPS Master GP, Inc., the Sole Member of CMS Master GP, LLC, General Partner of the Issuer) EDGAR ↗

No sales reported yet as of the latest filing. William 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.

Investing · group: Merion

CMS 2008 Investment Partners PE-Q, L.P.

Wynnewood, PA · Oct 20, 2008
  • Oct 20, 2008 · D · $0 sold of $500,000 · 0 investors · min. $2,500 · role: Executive Officer (of MSPS Master GP, Inc., the Sole Member of CMS Master GP, LLC, General Partner of the Issuer) EDGAR ↗

No sales reported yet as of the latest filing. William 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.

People around William 5

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

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

Paul Silberberg

Executive Officer, Director · 2 shared filings (2 issuers) · also on 5 other issuers

Paul Silberberg is on 7 issuers in total — a repeat sponsor. Their page lists every one.

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

William A. Landman

Executive Officer, Director · 2 shared filings (2 issuers) · also on 49 other issuers

William A. Landman is on 51 issuers in total — a repeat sponsor. Their page lists every one.

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

Mark I Solomon

Executive Officer, Director · 2 shared filings (2 issuers) · also on 8 other issuers

Mark I Solomon is on 10 issuers in total — a repeat sponsor. Their page lists every one.

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

Ingrid R. Welch

Executive Officer · 2 shared filings (2 issuers) · also on 5 other issuers

Ingrid R. Welch is on 7 issuers in total — a repeat sponsor. Their page lists every one.

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

Richard A. Mitchell

Executive Officer · 2 shared filings (2 issuers) · also on 27 other issuers

Richard A. Mitchell is on 29 issuers in total — a repeat sponsor. Their page lists every one.

The team behind the deals

Sponsor group

Merion

49 issuers · 65 filings · $411.5M reported sold · 2008–2026

One team, 49 deal companies. William Siegenthaler is listed on 2 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 William Siegenthaler.

Same business address

51 other issuers file from the same address (first 50 shown)

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 2 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 William Siegenthaler 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 2 issuers this person is listed on — nothing matched.

Public profiles and social

Websites and social links of the issuers William Siegenthaler is listed on: none on file. No website or social profile named in CMS 2008 Investment Partners PE, L.P.'s SEC filings (Form C, Reg A, Form ADV; checked Oct 24, 2026). Web search for this name: #373,293 of 374,652 in line (1,310 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 (Wynnewood, PA). Each opens in a new tab; what you find there is not verified by PartnerFacts.

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