Green Century Capital Management provides portfolio management for investment companies and selecting other managers.
Green Century Capital Management reports 4 clients. They include 3 investment companies and 1 other client. Of its assets, 100.0% ($1.36B across 4 accounts) are managed with discretion.
| Client type | Clients | Assets |
|---|---|---|
| Investment companies | 75% | 100% |
| Other | 25% | <1% |
Client breakdown and activity details
| Client type | Clients | Regulatory AUM | AUM share | Avg. per client |
|---|---|---|---|---|
| Investment companies | 3 | $1.36B | 100.0% | $453M |
| Other | 1 | $544K | 0.0% | $544K |
| Total | 4 | $1.36B | 100% | $340M |
- Clients
- 3
- Regulatory AUM
- $1.36B
- AUM share
- 100.0%
- Avg. per client
- $453M
- Clients
- 1
- Regulatory AUM
- $544K
- AUM share
- 0.0%
- Avg. per client
- $544K
Total
- Clients
- 4
- Regulatory AUM
- $1.36B
- AUM share
- 100%
- Avg. per client
- $340M
- Clients outside the U.S.
- 0%
- Clients advised without assets under management last fiscal year
- 0
- Private funds advised
- 0
Green Century Capital Management is paid through a percentage of assets under management; its fees and minimums are set out in its brochures on the SEC website.
Paradigm Partners owns 75% or more of Green Century Capital Management. The leadership team of Green Century Capital Management includes President Leslie Samuelrich and Chief Compliance Officer Joseph Guerin. It has 16 employees, 6 of them in advisory roles.
Staff
- 16 employees
- 6 in advisory functions
- 3 broker-dealer reps
- Owns 75% or more of Green Century Capital Management Inc
Paradigm Partners
Control person · since August 1991
Massachusetts Public Interest Research Group, Inc.
Partner · Control person · since August 1991
Fund for the Public Interest, Inc.
Partner · Control person · since August 1991
New Jersey Public Interest Research Group Citizen Lobby, Inc.
Partner · Control person · since August 1991
Connpirg Citizen Lobby, Inc.
Partner · Control person · since September 1992
California Public Interest Research Group, Inc.
Partner · Control person · since August 1991
Washington State Public Interest Research Group, Inc.
Partner · Control person · since June 1992
Missouri Public Interest Research Group Citizen Organization, Inc.
Partner · Control person · since May 1992
Pirgim Public Interest Lobby, Inc.
Partner · Control person · since February 1993
Colorado Public Interest Research Group, Inc.
Partner · Control person · since May 1992
Green Century Capital Management’s regulatory assets grew 1.9× from $726M (September 2020) to $1.36B (September 2026); clients were 4 in both filings and employees fell from 17 to 16.
Figures from each annual filing
| Filed | Regulatory AUM | Clients | StaffEmployees | Offices |
|---|---|---|---|---|
| Sep 2026September 2026 | $1.36B | 4 | 16 | 1 |
| Sep 2025September 2025 | $1.26B | 4 | 16 | 1 |
| Sep 2024September 2024 | $1.28B | 4 | 15 | 1 |
| Sep 2023September 2023 | $1.12B | 4 | 13 | 1 |
| Sep 2022September 2022 | $998M | 4 | 11 | 1 |
| May 2022May 2022 | $1.05B | 4 | 13 | 1 |
| Sep 2020September 2020 | $726M | 4 | 17 | 1 |
Besides its headquarters, Green Century Capital Management has 0 offices, with 1 listed address in 1 state.
Massachusetts · 1 listed address
- 22 Batterymarch Street Street Suite 5a, BostonHQ
Contact and registration details
- Legal name
- Green Century Capital Management Inc
- Headquarters
- 22 Batterymarch Street Street Suite 5a, Boston, MA 02109-2424
- Website
- greencentury.com
- Phone
- 617-482-0800
- SEC file
- 801-39630
- Structure
- Massachusetts corporation
- Fiscal year end
- June
Green Century Capital Management’s named custodian for separately managed accounts is Umb Financial Services ($128K). Green Century Capital Management does not have custody of client assets.
- Umb Financial ServicesUmb Financial Services, Inc. · Kansas City, MO · $128K100%
At year end, Green Century Capital Management’s separately managed accounts were mostly in stocks (100%).
What the accounts hold
- Stocks100%
How many clients does Green Century Capital Management have?
Green Century Capital Management has 4 clients and manages $1.36 billion for them, as of September 2026. They include 3 investment companies and 1 other client.
Source: Form ADV Part 1A, Items 5.D and 5.F, filed 30 September 2026
What services does Green Century Capital Management offer?
Green Century Capital Management provides portfolio management for investment companies and selecting other managers.
Source: Form ADV Part 1A, Item 5.G, from the SEC's 2 October 2026 data file
Which custodians does Green Century Capital Management use?
Green Century Capital Management’s separately managed account assets are held at Umb Financial Services, Inc. (Kansas City, MO), with $128K. Only custodians holding at least a tenth of those assets are named.
Source: Form ADV Part 1A, Schedule D, Section 5.K.(3), filed 30 September 2026
How many financial advisors does Green Century Capital Management have?
Green Century Capital Management has 0 investment adviser representatives registered with state securities authorities, out of 16 employees, and 6 perform investment advisory functions. 3 employees are registered representatives of a broker-dealer and 0 employees are licensed insurance agents.
Source: Form ADV Part 1A, Items 5.A and 5.B, from the SEC's 2 October 2026 data file
What does Green Century Capital Management invest in?
At the end of its last fiscal year, Green Century Capital Management’s separately managed accounts held 100% exchange-traded equities.
Source: Form ADV Part 1A, Items 5.K.(1) and 7.B, from the SEC's 2 October 2026 data file
Who owns Green Century Capital Management?
Green Century Capital Management’s direct owner is Paradigm Partners (75% or more).
Source: Form ADV Part 1A, Schedules A and B, filed 30 September 2026
How does Green Century Capital Management get paid?
Green Century Capital Management is paid through a percentage of assets under management. Its Form ADV lists no commissions or performance-based fees among how it is paid.
Source: Form ADV Part 1A, Item 5.E, from the SEC's 2 October 2026 data file
How do I contact Green Century Capital Management?
Green Century Capital Management’s main office is at 22 Batterymarch Street Street Suite 5a, Boston, MA 02109-2424. Its phone number is 617-482-0800. Its website is greencentury.com.