# Impax Asset Management LLC

> Impax Asset Management LLC is an SEC-registered investment advisory firm in Portsmouth, NH, registered since 1972, reporting over $5 billion in regulatory assets under management in its Form ADV filing dated September 29, 2026.

- CRD: 114335
- Filed as: IMPAX ASSET MANAGEMENT LLC
- Registration: SEC-registered investment adviser (status as filed: Approved)
- Location: Portsmouth, NH
- Filing period: October 2026
- Form ADV filing dated: September 29, 2026
- SEC record (IAPD): https://adviserinfo.sec.gov/firm/summary/114335
- AdvisorCensus page: https://advisorcensus.com/firm/impax-asset-management-llc-portsmouth-nh-114335

## Quick answers

**How is Impax Asset Management LLC compensated?**
On its Form ADV (Item 5.E, October 2026), Impax Asset Management LLC reports these compensation arrangements: a percentage of assets under its management. The amounts are in Item 5 of its Form ADV Part 2A brochure.

**Where is Impax Asset Management LLC located?**
Impax Asset Management LLC's principal office is in Portsmouth, NH, according to its Form ADV; the October 2026 filing also lists 1 other office (Schedule D, Section 1.F).

**Is Impax Asset Management LLC registered with the SEC or a state?**
Impax Asset Management LLC is an SEC-registered investment advisory firm, registered since 1972. Status as filed: Approved. CRD 114335.

**How much does Impax Asset Management LLC manage?**
Impax Asset Management LLC reports $8,942,785,264 in regulatory assets under management in its Form ADV filing dated September 29, 2026 (100% discretionary).

**How have Impax Asset Management LLC's assets and staff changed since 2021?**
In the Form ADV data for Impax Asset Management LLC: Regulatory assets under management: $5,332,933,707 in the October 2021 data and $8,942,785,264 in the October 2026 data, up 68%. Total employees: 62 in October 2021 and 93 in October 2026. Assets under management move with markets as well as with clients coming and going.

**What types of clients does Impax Asset Management LLC serve?**
By number of clients on Form ADV Item 5.D: investment companies (12); other investment advisers (8); pooled investment vehicles (other than investment companies and business development companies) (7).

**Which custodians does Impax Asset Management LLC use?**
Impax Asset Management LLC's most recent Form ADV filing (Schedule D, Section 5.K(3)) lists BNY Mellon, Caceis Bank and State Street Bank as custodians holding 10% or more of its separately managed account assets.

**Does Impax Asset Management LLC report any disciplinary disclosures?**
Reports no disclosure items on Form ADV Item 11. The detail of any item is on the firm's SEC record: https://adviserinfo.sec.gov/firm/summary/114335

**What changed in Impax Asset Management LLC's recent Form ADV filings?**
In the January 2026 filing data: Employees performing advisory functions went from 36 to 30. Registered or notice-filed in CA, CO, CT, FL, IL, MA, MD, ME, NY. Updated its list of owners and control persons (Schedule A).

## From the Form ADV filing

### Compensation (Item 5.E)
- A percentage of assets under your management

### Custodians (Schedule D, Section 5.K(3))
- BNY Mellon
- Caceis Bank
- State Street Bank

Custodians holding 10% or more of the firm's separately managed account assets, as filed on Form ADV (Schedule D, Section 5.K(3)). A custodian holds client assets; it does not endorse or supervise the firm. AdvisorCensus has no relationship with any custodian.

### Regulatory assets under management (Item 5.F)
- Total: $8,942,785,264
- Discretionary: $8,942,785,264
- Non-discretionary: $0

### Clients (Item 5.D)

| Client type | Clients | Assets |
| --- | --- | --- |
| Investment companies | 12 | $7,789,559,737 |
| Pooled investment vehicles (other than investment companies and business development companies) | 7 | $1,024,868,402 |
| Other investment advisers | 8 | $128,357,125 |

### Advisory services (Item 5.G)
- Portfolio management for investment companies (and business development companies)
- Portfolio management for pooled investment vehicles (other than investment companies)
- Portfolio management for businesses (other than small businesses) or institutional clients

### Firm details
- Registered since: 1972 (54 years)
- Employees: 93 total, 30 performing advisory functions
- Wrap fee program participation: No
- States registered or notice-filed: CA, CO, CT, FL, IL, MA, MD, ME, NH, NY
- Disclosures (Item 11): Reports no disclosure items on Form ADV Item 11.

### Other offices (Schedule D, Section 1.F), as of the October 2026 filing
- New York, NY

### Websites listed on Form ADV (Item 1.I)
- impaxam.com
- LinkedIn @impax-funds-us

## Assets and staff over time

| Data period | Regulatory assets under management | Employees | Filing dated |
| --- | --- | --- | --- |
| October 2021 | $5,332,933,707 | 62 | December 23, 2020 |
| October 2022 | $8,533,503,708 | 77 | April 12, 2022 |
| October 2023 | $7,540,692,270 | 104 | January 18, 2023 |
| October 2024 | $9,078,719,479 | 115 | April 2, 2024 |
| October 2025 | $9,643,533,263 | 113 | December 20, 2024 |
| October 2026 | $8,942,785,264 | 93 | September 29, 2026 |

Regulatory assets under management: $5,332,933,707 in the October 2021 data and $8,942,785,264 in the October 2026 data, up 68%.
Total employees: 62 in October 2021 and 93 in October 2026.

## Changes in the filing (last 12 months)

### January 2026
- Employees performing advisory functions went from 36 to 30.
- Registered or notice-filed in CA, CO, CT, FL, IL, MA, MD, ME, NY.
- Updated its list of owners and control persons (Schedule A).

## Source

Form ADV as filed, October 2026. Values appear as filed. Cite as: AdvisorCensus. Impax Asset Management LLC (CRD 114335): Form ADV filing data as of October 2026.