# D. Mattersdorff LLC

> D. Mattersdorff LLC is a state-registered investment advisory firm in Lake Oswego, OR, registered since 1999, reporting $25 million to $100 million in regulatory assets under management in its Form ADV filing dated March 27, 2026.

- CRD: 134150
- Filed as: D. MATTERSDORFF LLC
- Registration: State-registered investment adviser (status as filed: APPROVED)
- Location: Lake Oswego, OR
- Filing period: October 2026
- Form ADV filing dated: March 27, 2026
- Public record (IAPD): https://adviserinfo.sec.gov/firm/summary/134150
- AdvisorCensus page: https://advisorcensus.com/firm/d-mattersdorff-llc-lake-oswego-or-134150

## Quick answers

**How is D. Mattersdorff LLC compensated?**
On its Form ADV (Item 5.E, October 2026), D. Mattersdorff LLC reports these compensation arrangements: a percentage of assets under its management; hourly charges.

**Where is D. Mattersdorff LLC located?**
D. Mattersdorff LLC's principal office is in Lake Oswego, OR, according to its Form ADV.

**Is D. Mattersdorff LLC registered with the SEC or a state?**
D. Mattersdorff LLC is a state-registered investment advisory firm, registered since 1999. Status as filed: APPROVED. CRD 134150.

**How much does D. Mattersdorff LLC manage?**
D. Mattersdorff LLC reports $61,898,075 in regulatory assets under management in its Form ADV filing dated March 27, 2026 (100% discretionary).

**What types of clients does D. Mattersdorff LLC serve?**
By number of clients on Form ADV Item 5.D: high net worth individuals (11); individuals (other than high net worth individuals) (5).

**Does D. Mattersdorff LLC report any disciplinary disclosures?**
Reports no disclosure items on Form ADV Item 11. The detail of any item is on the firm's public record on IAPD: https://adviserinfo.sec.gov/firm/summary/134150

## From the Form ADV filing

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

### Regulatory assets under management (Item 5.F)
- Total: $61,898,075
- Discretionary: $61,898,075
- Non-discretionary: $0

### Clients (Item 5.D)

| Client type | Clients | Assets |
| --- | --- | --- |
| Individuals (other than high net worth individuals) | 5 | $1,832,036 |
| High net worth individuals | 11 | $60,066,039 |

### Advisory services (Item 5.G)
- Financial planning services
- Portfolio management for individuals and/or small businesses

### Firm details
- Registered since: 1999 (27 years)
- Employees: 1 total, 1 performing advisory functions
- Wrap fee program participation: No
- States registered or notice-filed: CA, OR
- Disclosures (Item 11): Reports no disclosure items on Form ADV Item 11.

### Websites listed on Form ADV (Item 1.I)
- mattersdorff.com
- LinkedIn @donald-mattersdorff-7b72852
- X @dmatters

## Source

Form ADV as filed, October 2026. Values appear as filed. Cite as: AdvisorCensus. D. Mattersdorff LLC (CRD 134150): Form ADV filing data as of October 2026.