Data / Investment advisers / Massachusetts / Longfellow Investment Management Co. LLC
Longfellow Investment Management Co. LLC, Boston, MA: $23.4 billion AUM, SEC registered investment adviser
Updated November 7, 2026. Source: the SEC's Form ADV data files for investment advisers.
Longfellow Investment Management Co. LLC is an SEC registered investment adviser with its main office in Boston, Massachusetts and reports $23.4 billion in regulatory assets under management in its Form ADV filed August 6, 2026. Its clients include pension and profit sharing plans, state and municipal governments and corporations and other businesses. It is paid through a percentage of assets under management, fixed fees and performance based fees.
The request: Watch Longfellow Investment Management Co. LLC (CRD number 104945): each new Form ADV amendment, with AUM, clients and private funds. $10 of work on sign-up, no card.
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- Registration
- SEC registered investment adviser
- CRD number
- 104945
- SEC file number
- 801-27485
- SEC status
- Approved, effective July 21, 1986
- Main office
- 125 High Street Suite 832, Boston, MA 02110
- Phone
- (617) 695-3504
- Website
- longfellowim.com
- Regulatory AUM
- $23,442,074,430 in the Form ADV filed August 6, 2026
- Discretionary AUM
- $23,442,074,430
- Accounts
- 192
- Employees
- 51, of which 24 give investment advice
- Form of organization
- Limited Liability Company
- Paid through
- a percentage of assets under management, fixed fees, performance based fees
- Form ADV Item 11 disclosures
- None reported
- Latest Form ADV filing
- August 6, 2026
- SEC record
- Investment Adviser Public Disclosure
Clients
Client types the adviser reports in Form ADV item 5.D, with the AUM it attributes to each.
| Client type | Clients | AUM |
|---|---|---|
| Pension and profit sharing plans | 23 | $7.24 billion |
| State or municipal government entities | 24 | $6.10 billion |
| Corporations or other businesses | 35 | $5.10 billion |
| Charitable organizations | 43 | $3.31 billion |
| Insurance companies | 18 | $1.02 billion |
| Banking or thrift institutions | 1 | $327 million |
| High net worth individuals | 15 | $240.3 million |
| Investment companies | 1 | $100.4 million |
| Pooled investment vehicles | 1 | $3.6 million |
AUM in the SEC's monthly files
Each change in the AUM the adviser reported across the monthly SEC files held here, with the first file that shows the new value.
| First in the file of | AUM | Form ADV filed |
|---|---|---|
| April 1, 2026 | $23.44 billion | March 23, 2026 |
| December 1, 2025 | $18.93 billion | July 2, 2025 |
Other advisers in Boston
| Adviser | City | AUM | Private funds | Source |
|---|---|---|---|---|
| PSG Equity L.L.C. | Boston | $30.18 billion | 56 | adviserinfo.sec.gov |
| Westfield Capital Management Company, L.P. | Boston | $29.81 billion | 2 | adviserinfo.sec.gov |
| Berkshire Partners LLC | Boston | $29.00 billion | 26 | adviserinfo.sec.gov |
| MDT Advisers, a Division of Federated Mdta LLC | Boston | $25.95 billion | Not listed | adviserinfo.sec.gov |
| The Baupost Group, L.L.C. | Boston | $24.68 billion | 12 | adviserinfo.sec.gov |
| Capital Advisors Group, Inc | Boston | $23.03 billion | Not listed | adviserinfo.sec.gov |
| THL Managers VII, LLC | Boston | $21.48 billion | 26 | adviserinfo.sec.gov |
| Charlesbank Capital Partners, LLC | Boston | $21.06 billion | 50 | adviserinfo.sec.gov |
Also on SpecStream
- Investment advisers in Boston, MA
- Investment advisers in Massachusetts
- Advisers with $10 billion to $100 billion in AUM
- Advisers serving pension and profit sharing plans
- Advisers serving state and municipal governments
- Longfellow Investment Management Co. LLC on the SEC's adviser search
Public data published by the US Securities and Exchange Commission (US government work). Advisers report these values themselves in Form ADV, and neither the SEC nor the states approve or guarantee them. AUM is regulatory assets under management as the adviser reported it in Form ADV item 5.F, which can differ from the AUM a firm quotes elsewhere. Exempt reporting advisers do not report AUM. Office address, phone and website are the adviser's main office as filed; a firm that files its main office as a private residence shows no street address or phone. An Item 11 disclosure is a reported event, not a finding about the firm today. Details for each firm are on the SEC's Investment Adviser Public Disclosure site. This page uses SEC data and is not endorsed or certified by the SEC. Free to reuse with credit to SpecStream under CC BY 4.0. Spot a wrong value? Write to [email protected] with the link to this page.