Oberweis Asset Management Inc
- Regulatory AUM
- $5.1B
- Discretionary
- $5.1B
- Clients
- 108
- Avg AUM / client
- $46.9M
- Accounts
- 110
- Employees
- 31
AUM over time
Annual snapshots from Form ADV filings · as of Mar 31, 2026
Investments (13F portfolio — 180 positions, $3,385,664,734)
13F period Mar 31, 2026| # | Issuer | Class | Value | Shares | % of 13F | % of AUM |
|---|---|---|---|---|---|---|
| 1 | Applied Optoelectronics Inc. | COM | $198,783,878 | 2,349,969 | 5.87% | 3.93% |
| 2 | Lumentum Hldgs, Inc. | COM | $187,090,173 | 266,222 | 5.53% | 3.7% |
| 3 | Credo Technology Group | COM | $95,932,136 | 1,021,968 | 2.83% | 1.9% |
| 4 | Digital Ocean Holdings, Inc. | COM | $79,561,379 | 927,505 | 2.35% | 1.57% |
| 5 | Shark Ninja, Inc. | COM | $63,536,823 | 599,970 | 1.88% | 1.26% |
| 6 | Nova Ltd. | COM | $59,911,097 | 137,955 | 1.77% | 1.18% |
| 7 | Dana Inc. | COM | $54,226,975 | 1,611,500 | 1.6% | 1.07% |
| 8 | Bright Spring Health Services | COM | $49,383,712 | 1,158,970 | 1.46% | 0.98% |
| 9 | Macom Technology Solutions | COM | $47,941,804 | 215,886 | 1.42% | 0.95% |
| 10 | Rambus, Inc | COM | $45,278,965 | 526,316 | 1.34% | 0.89% |
| 11 | Clean Harbors, Inc. | COM | $41,390,909 | 144,355 | 1.22% | 0.82% |
| 12 | Si Time Corporation | COM | $41,193,693 | 119,281 | 1.22% | 0.81% |
| 13 | Ultra Clean Holdings | COM | $39,824,798 | 640,476 | 1.18% | 0.79% |
| 14 | Everus Construction Group | COM | $38,550,486 | 326,533 | 1.14% | 0.76% |
| 15 | Frontdoor, Inc. | COM | $37,951,366 | 717,960 | 1.12% | 0.75% |
| 16 | Carpenter Technology Corp. | COM | $37,220,897 | 94,433 | 1.1% | 0.74% |
| 17 | Skywest Inc | COM | $36,043,183 | 392,499 | 1.06% | 0.71% |
| 18 | Lattice Semiconductor Corporat | COM | $34,732,683 | 374,436 | 1.03% | 0.69% |
| 19 | Globus Medical, Inc. A | COM | $33,791,952 | 392,200 | 1.0% | 0.67% |
| 20 | Camtek, Ltd. | COM | $33,775,676 | 222,780 | 1.0% | 0.67% |
| 21 | Arcutis Biotherapeutics, Inc. | COM | $32,181,570 | 1,365,941 | 0.95% | 0.64% |
| 22 | Flowserve Corporation | COM | $31,953,415 | 434,681 | 0.94% | 0.63% |
| 23 | Silicon Motion Techn Adr | COM | $31,727,540 | 282,550 | 0.94% | 0.63% |
| 24 | Life Time Holdings, Inc. | COM | $31,263,870 | 1,160,500 | 0.92% | 0.62% |
| 25 | Rush Street Interactive, Inc. | COM | $31,201,680 | 1,434,560 | 0.92% | 0.62% |
Top 25 of 180 positions from the manager's latest Form 13F · source filing (EDGAR) ↗. 13F covers long US-listed positions only. "% of AUM" is share of the firm's total regulatory AUM (Form ADV Item 5.F).
Who they serve
| Client type | Clients | AUM | % of AUM |
|---|---|---|---|
| Individuals (non-high net worth) | 30 | $14.7M | 0.29% |
| High net worth individuals | 36 | $49.9M | 0.99% |
| Investment companies | 6 | $3.2B | 63.9% |
| Pooled investment vehicles (non-investment companies) | 1 | $48.8M | 0.96% |
| Charitable organizations | Fewer than 5 clients | $33.3M | 0.66% |
| State or municipal government entities | 7 | $1.4B | 27.7% |
| Corporations and other businesses | 12 | $278M | 5.5% |
| Other | 16 | $1.2M | 0.02% |
Private funds (1)
Reported in Form ADV Section 7.B.(1), filing of Oct 2024 · $36.8M combined gross assets
| Fund | Type | Domicile | Gross assets | Owners |
|---|---|---|---|---|
| Oberweis International Select Fund, Llc | Other Private Fund | Delaware | $36.8M | 17 |
People (10)
roster as of Jul 20, 2026| Name | Role / title | Credentials | With firm since | Ownership |
|---|---|---|---|---|
| Oberweis, James, Donald | Shareholder | Sep 1994 (32y) | 10% – 25% | |
| James Walter Oberweis | Chairman, President, Shareholder And Director | Nov 1994 (32y) | 50% – 75% | |
| Hannemann, Eric, Vicary | Chief Financial Officer, Treasurer | Sep 2022 (4y) | Less than 5% | |
| Joyce, Thomas, Patrick | Chief Compliance Officer, Secretary | Sep 2022 (4y) | Less than 5% | |
| David Isidarus Covas | Registered representative | CFP | Oct 2001 (25y) | |
| Scott Valey Braser | Registered representative | Jun 2017 (9y) | ||
| John Carol Tyrpin | Registered representative | Jun 2017 (9y) | ||
| Brett Allen Pierson | Registered representative | May 2021 (5y) | ||
| Thomas Russell Labelle | Registered representative | May 2022 (4y) | ||
| Benjamin Aaron Krimmel | Registered representative | Oct 2024 (2y) |
Undisclosed: 0% – 40% of the firm is not attributable from the filed Schedule A bands.
Roster from the IAPD representatives feed; ownership and acquisition dates from Form ADV Schedule A/B. "Since" is the earliest filed registration or acquisition date.
Private funds (1, $36.8M gross assets)
| Fund | Type | Gross assets | Min. investment | Owners |
|---|---|---|---|---|
| Oberweis International Select Fund, Llc | Other Private Fund | $36.8M | $5.0M | 17 |
From Form ADV Section 7.B private fund reporting.
Documents (1 archived)
| Form | Period | Size | |
|---|---|---|---|
| Form ADV (full filing) | 03/31/2026 | 1.25 MB | View · PDF · Source ↗ |
Archived copies of the firm's regulatory filings, versioned by content hash.
Disciplinary disclosures
No disciplinary events reported on the firm's latest Form ADV filing.
How they charge
- • Percentage of assets under management
- • Other fees
- • PROVIDE MODEL PORTFOLIO DATA TO CLIENTS
Services
- • Portfolio management for individuals/small businesses
- • Portfolio management for investment companies
- • Portfolio management for pooled investment vehicles
- • Portfolio management for businesses/institutional clients
Custody
Reported custodians
- Northern Trust $841M (17% of AUM) Mar 2026
- BNY Mellon $838M (17% of AUM) Mar 2026
- State Street $175M (6% of AUM) Mar 2019
- RBC $166M (6% of AUM) Mar 2019
Amounts as reported in ADV Item 5.K.(3) (custodians holding 10%+ of SMA assets).
Firm reports it does not have custody of client funds or securities (Item 9.A).
Source
All data on this page comes from this firm's Form ADV filings, reproduced without modification. Latest filing: Mar 31, 2026.
View current Form ADV (SEC/IAPD) ↗