{"url":"https://nivawealth.com/firms/mainline-investment-advisers-159045","iapdUrl":"https://adviserinfo.sec.gov/firm/summary/159045","regulatoryAum":109927979,"crd":"159045","adviserRoster":{"asOf":"2026-10-09","items":[{"crd":"5644079","suffix":null,"lastName":"CLAPPER","firstName":"DAVID","middleName":"ANDREW"},{"crd":"4342118","suffix":null,"lastName":"LANDMAN","firstName":"WILLIAM","middleName":"ALAN"}],"total":2,"loadedAt":"2026-10-10T00:20:19.761928+00:00","sourceUrl":"https://reports.adviserinfo.sec.gov/reports/CompilationReports/IA_INDVL_Feed_10_09_2026.xml.zip"},"history":[{"filedOn":"2021-05-03","regulatoryAum":296577975,"clients":11,"employees":6,"offices":1},{"filedOn":"2022-03-30","regulatoryAum":435072100,"clients":16,"employees":5,"offices":1},{"filedOn":"2023-04-28","regulatoryAum":296489320,"clients":13,"employees":5,"offices":1},{"filedOn":"2024-07-19","regulatoryAum":244810132,"clients":9,"employees":6,"offices":1},{"filedOn":"2025-04-29","regulatoryAum":200838563,"clients":15,"employees":5,"offices":1},{"filedOn":"2026-09-01","regulatoryAum":109927979,"clients":16,"employees":4,"offices":1}],"secFileNumber":"801-72761","legalName":"Mainline Investment Advisers, LLC","displayName":"Mainline Investment Advisers","slug":"mainline-investment-advisers-159045","website":"https://mainlineco.com/","classification":{"segment":"private_funds","segmentLabel":"Private funds","type":"private_fund_manager","typeLabel":null,"feeDisclosure":"payment_only"},"linkedinUrl":"https://www.linkedin.com/company/mainline-investment-advisors/","founded":null,"organization":"Delaware limited liability company","fiscalYearEnd":"December","headquarters":{"street":"308 E. Lancaster Avenue, Suite 300","city":"Wynnewood","state":"PA","stateName":"Pennsylvania","country":"United States","postalCode":"19096-2145"},"tradeNames":["Mainline Companies","Mainline Investments"],"registration":{"secApproved":"5 October 2011","noticeFilings":null,"latestNoticeFiling":null},"wealthAumPerClient":285714.28571428574,"staff":{"employees":4,"advisory":3,"brokerDealerReps":1,"insuranceAgents":1,"promoters":0},"aum":{"regulatory":109927979,"discretionary":84439443,"discretionaryAccounts":6,"nonDiscretionary":25488536,"nonDiscretionaryAccounts":9,"wrapProgram":null,"nonUsClientsPct":0,"nonAumClients":1},"clientTypes":[{"label":"High-net-worth individuals","clients":7,"regulatoryAum":2000000},{"label":"Pooled investment vehicles","clients":9,"regulatoryAum":107927979}],"feePrograms":[],"brochureCoverage":{"scope":"known_documents","status":"not_processed","checkedAt":null,"documents":[]},"custodians":[],"custodyNote":"Mainline Investment Advisers has custody of $28.8M in client assets for 6 clients.","otherCustodians":[],"leadership":[{"name":"William Landman","title":"President, Chief Executive Officer","crd":"4342118"},{"name":"David Clapper","title":"Vice President, Secretary, Chief Operations Officer","crd":"5644079"},{"name":"Donna Rittershausen","title":"Chief Compliance Officer","crd":"1480201"}],"ownership":[{"label":"Mainline Investment Partners, LLC","detail":"Sole managing member - 100% owner in the 75% or more ownership band and a control person, since August 2011."},{"label":"William Landman","detail":"Indirect owner: a managing member of Mainline Investment Partners, LLC in the 50% to 75% band and a control person, since August 2011.","parent":"Mainline Investment Partners, LLC"},{"label":"David Clapper","detail":"Indirect owner: a member/partner and minority owner of Mainline Investment Partners, LLC in the 25% to 50% band and a control person, since August 2011.","parent":"Mainline Investment Partners, LLC"}],"branchOffices":null,"filedOffices":{"otherThanPrincipal":0,"privateResidences":0},"listedOfficeAddresses":1,"foreignOffices":[],"officesByState":[{"state":"Pennsylvania","offices":1,"addresses":[{"street":"308 E. Lancaster Avenue, Suite 300","city":"Wynnewood","headquarters":true}]}],"advFacts":{"source":{"file":"ia100226.zip","asOf":"2 October 2026"},"telephone":"610-896-3000","stateRegisteredReps":2,"otherAdviserReps":0,"compensation":["A percentage of assets under management","Fixed fees (other than subscription fees)","Performance-based fees","Other"],"activities":["Portfolio management for individuals and/or small businesses","Portfolio management for pooled investment vehicles (other than investment companies)"],"financialPlanningClients":null,"assetMix":[{"label":"Other","percent":100,"detail":"Privately-Issued Securities Obtained in A Private Placement (Securities That Are Acquired From the Issuer in Transaction(s) Not Involving A Public Offering; Uncertificated and Ownership Thereof Is Recorded Only on the Books of the Issuer in Name of the Client; and Transferable Only With the Prior Consent of the Issuer.)"}],"privateFunds":8},"sources":{"adv1FilingDate":"1 September 2026","adv1Url":"https://reports.adviserinfo.sec.gov/reports/ADV/159045/PDF/159045.pdf","brochureDate":null,"brochureUrl":null,"iapdCompiledDate":null,"retrievedDate":"15 October 2026","retrievedOn":"2026-10-15","updatedOn":"2026-10-21","holdingsUpdatedOn":"2026-10-21","adv1Pages":{},"brochurePages":{}},"otherBusiness":[],"faq":[{"question":"How many clients does Mainline Investment Advisers have?","answer":"Mainline Investment Advisers has 16 clients and manages $110 million for them, as of September 2026. They include 9 pooled investment vehicles and 7 high-net-worth individuals.","source":"Form ADV Part 1A, Items 5.D and 5.F, filed 1 September 2026","sourceRef":{"doc":"adv1","section":"employees"}},{"question":"What services does Mainline Investment Advisers offer?","answer":"Mainline Investment Advisers provides portfolio management for individuals and small businesses and portfolio management for pooled vehicles.","source":"Form ADV Part 1A, Item 5.G, from the SEC's 2 October 2026 data file","sourceRef":{"doc":"adv1","section":"employees"}},{"question":"How many financial advisors does Mainline Investment Advisers have?","answer":"Mainline Investment Advisers has 2 investment adviser representatives registered with state securities authorities, out of 4 employees, and 3 perform investment advisory functions. 1 employee is a registered representative of a broker-dealer and 1 employee is a licensed insurance agent.","source":"Form ADV Part 1A, Items 5.A and 5.B, from the SEC's 2 October 2026 data file","sourceRef":{"doc":"adv1","section":"employees"}},{"question":"What does Mainline Investment Advisers invest in?","answer":"At the end of its last fiscal year, Mainline Investment Advisers’ separately managed accounts held 100% other. The 100% other category is described as: Privately-Issued Securities Obtained in A Private Placement (Securities That Are Acquired From the Issuer in Transaction(s) Not Involving A Public Offering; Uncertificated and Ownership Thereof Is Recorded Only on the Books of the Issuer in Name of the Client; and Transferable Only With the Prior Consent of the Issuer.). It advises 8 private funds.","source":"Form ADV Part 1A, Items 5.K.(1) and 7.B, from the SEC's 2 October 2026 data file","sourceRef":{"doc":"adv1","section":"employees"}},{"question":"Who owns Mainline Investment Advisers?","answer":"Mainline Investment Advisers is owned through a holding company by William Landman and David Clapper. Its direct owner is Mainline Investment Partners, LLC (75% or more).","source":"Form ADV Part 1A, Schedules A and B, filed 1 September 2026","sourceRef":{"doc":"adv1","section":"scheduleA"}},{"question":"How does Mainline Investment Advisers get paid?","answer":"Mainline Investment Advisers is paid through a percentage of assets under management, fixed fees, performance-based fees and other compensation. Its Form ADV lists no commissions among how it is paid.","source":"Form ADV Part 1A, Item 5.E, from the SEC's 2 October 2026 data file","sourceRef":{"doc":"adv1","section":"employees"}},{"question":"How do I contact Mainline Investment Advisers?","answer":"Mainline Investment Advisers’ main office is at 308 E. Lancaster Avenue, Suite 300, Wynnewood, PA 19096-2145. Its phone number is 610-896-3000. Its website is mainlineco.com.","source":"Form ADV Part 1A, Item 1.F, filed 1 September 2026","sourceRef":{"doc":"adv1","section":"offices"}}],"holdings":null,"notice":"Compiled from public SEC Form ADV filings on the dates in `sources`. Facts as filed; not a rating, ranking, or recommendation. Niva is not affiliated with this firm. Disciplinary history is deliberately not included here or on the page; the SEC publishes the complete record at the `iapdUrl` above."}