Reported positions
Quarter-end holdings as filed
Explore the full published position list and its source filing. This record excludes the manager’s cash, shorts and non-13(f) assets.
OBERWEIS ASSET MANAGEMENT INC/
- sum of disclosed values for 2026-03-31; 0 positions carry a NULL value and are excluded from the sum, surfaced here rather than folded away
- $3.4B
- ALL retained default holdings for this (filer, period), including NULL-value ones
- 180
- positions with no comparable holding in the prior quarter (kind new), 2026-03-31
- 22
- positions absent from this quarter's filing after being held last quarter (kind exit), 2026-03-31 — inferred from absence, not a sale record
- 21
A quarter-end snapshot. Filed up to 45 days later, so this page is not current holdings and never a complete portfolio. what a 13F is — and is not ↓ methodology §13F ↗
Position changes — into 2026-03-31
by shares · Δ value · filing link · how changes are classified §Period
position matched across quarters by exact reported CUSIP over a registry gap — producer-reconciled identity, never a name match identity_reconciled_by_cusip | the reported share count is unchanged across the pair; this build's data classified the change from its reported value; builds from 2026-09-10 on read it as NO CHANGE classified_by_value · EXIT = absent this quarter: disposed, delisted, under confidential treatment, or reported instead by an affiliated manager — the filing does not say which · change not classifiable: value undisclosed on one side of the quarter pair, or neither shares nor value can classify it · NO CHANGE = the share count is identical in both quarters; the value moved only with price, so the row is mark-to-market and never an ADD or a TRIM (NEW / ADD / TRIM / EXIT / NO CHANGE) · NO PRIOR = this filer has no comparable holdings list for the previous quarter on record — a first filing under this registration, or a quarter reported inside an affiliated manager's filing — so the position is not called a new stake | derived by Public Filings from the published aggregate; NULL means the source did not disclose a usable value — never zero | Prev value | Curr value | Prev shares | Curr shares | |
|---|---|---|---|---|---|---|---|
position key pos:17760 · issuer key iss:150 COM | ADD | +$128M | +310,328 | $71.1M | $199M | 2,039,641 | 2,349,969 |
position key pos:17670 · issuer key iss:1145 COM | TRIM | +$83.5M | −14,708 | $104M | $187M | 280,930 | 266,222 |
position key pos:15416 · issuer key iss:2080 COM | ADD | −$1.2M | +346,580 | $97.2M | $95.9M | 675,388 | 1,021,968 |
position key pos:13589 · issuer key iss:584 COM | ADD | +$42.1M | +148,675 | $37.5M | $79.6M | 778,830 | 927,505 |
position key pos:10705 · issuer key iss:2209 COM | ADD | +$4.6M | +73,660 | $58.9M | $63.5M | 526,310 | 599,970 |
position key pos:13280 · issuer key iss:2278 COM | ADD | +$22.7M | +24,670 | $37.2M | $59.9M | 113,285 | 137,955 |
position key pos:15579 · issuer key iss:555 COM | ADD | +$35.3M | +815,000 | $18.9M | $54.2M | 796,500 | 1,611,500 |
position key pos:18251 · issuer key iss:315 COM | ADD | +$15.4M | +250,970 | $34.0M | $49.4M | 908,000 | 1,158,970 |
position key pos:16514 · issuer key iss:1163 COM | ADD | +$17.3M | +36,926 | $30.7M | $47.9M | 178,960 | 215,886 |
position key pos:17656 · issuer key iss:1520 COM | ADD | +$2.8M | +64,216 | $42.5M | $45.3M | 462,100 | 526,316 |
position key pos:10478 · issuer key iss:460 COM | ADD | +$14.0M | +27,485 | $27.4M | $41.4M | 116,870 | 144,355 |
position key pos:12212 · issuer key iss:1668 COM | ADD | +$3.6M | +12,885 | $37.6M | $41.2M | 106,396 | 119,281 |
position key pos:10837 · issuer key iss:1850 COM | ADD | +$23.9M | +11,976 | $15.9M | $39.8M | 628,500 | 640,476 |
position key pos:10574 · issuer key iss:698 COM | ADD | +$16.3M | +66,733 | $22.2M | $38.6M | 259,800 | 326,533 |
position key pos:12120 · issuer key iss:783 COM | ADD | +$2.7M | +107,100 | $35.2M | $38.0M | 610,860 | 717,960 |
position key pos:15744 · issuer key iss:402 COM | ADD | +$11.2M | +11,822 | $26.0M | $37.2M | 82,611 | 94,433 |
position key pos:15605 · issuer key iss:1673 COM | ADD | −$2.3M | +10,279 | $38.4M | $36.0M | 382,220 | 392,499 |
position key pos:15974 · issuer key iss:1099 COM | ADD | +$11.6M | +59,800 | $23.2M | $34.7M | 314,636 | 374,436 |
position key pos:17000 · issuer key iss:829 COM | ADD | +$10.2M | +122,200 | $23.6M | $33.8M | 270,000 | 392,200 |
position key sid:sec:prov:56bae275e7c8ff6b3019599a71e87dec · issuer key cusip6:M20791 COM | ADD | +$10.5M | +3,900 | $23.3M | $33.8M | 218,880 | 222,780 |
position key sid:sec:prov:fa36e00268ee3d6d74f8ff5697fdd99c · issuer key cusip6:03969K COM | ADD | +$8.7M | +557,541 | $23.5M | $32.2M | 808,400 | 1,365,941 |
position key pos:16204 · issuer key iss:755 COM | ADD | +$3.5M | +24,740 | $28.4M | $32.0M | 409,941 | 434,681 |
position key sid:sec:prov:a74e38bfd7e93554eeff15850e62a61f · issuer key cusip6:82706C COM | ADD | +$9.8M | +46,250 | $21.9M | $31.7M | 236,300 | 282,550 |
position key pos:16668 · issuer key iss:1119 COM | ADD | +$3.1M | +101,200 | $28.2M | $31.3M | 1,059,300 | 1,160,500 |
position key pos:12240 · issuer key iss:1583 COM | ADD | +$3.8M | +22,850 | $27.4M | $31.2M | 1,411,710 | 1,434,560 |
position key pos:18178 · issuer key iss:747 COM | ADD | +$10.2M | +34,365 | $20.9M | $31.1M | 131,300 | 165,665 |
position key pos:13976 · issuer key iss:723 COM | ADD | +$24.1M | +381,222 | $7.0M | $31.1M | 689,800 | 1,071,022 |
position key pos:11477 · issuer key iss:1832 COM | ADD | +$4.5M | +6,700 | $26.0M | $30.4M | 387,200 | 393,900 |
position key pos:15940 · issuer key iss:614 COM | ADD | +$5.6M | +193,993 | $24.8M | $30.3M | 404,500 | 598,493 |
position key sid:sec:prov:ff305e5d71d778fecd58cf4c7769a673 · issuer key cusip6:83418M COM | ADD | +$13.2M | +164,989 | $16.9M | $30.1M | 366,900 | 531,889 |
position key pos:11386 · issuer key iss:1217 COM | ADD | +$5.6M | +155,449 | $23.7M | $29.2M | 268,760 | 424,209 |
position key pos:15882 · issuer key iss:726 COM | ADD | +$10.9M | +101,134 | $18.1M | $28.9M | 166,500 | 267,634 |
position key pos:15739 · issuer key iss:111 COM | ADD | +$4.7M | +14,000 | $24.1M | $28.8M | 835,900 | 849,900 |
position key pos:17669 · issuer key iss:1215 COM | TRIM | −$1.7M | −23,017 | $30.2M | $28.5M | 414,040 | 391,023 |
position key pos:14112 · issuer key iss:159 COM | ADD | +$4.9M | +46,100 | $23.6M | $28.4M | 221,600 | 267,700 |
position key pos:12303 · issuer key iss:1343 COM | ADD | +$2.4M | +5,193 | $25.9M | $28.3M | 101,400 | 106,593 |
position key pos:17168 · issuer key iss:518 COM | ADD | +$12.5M | +91,400 | $15.8M | $28.3M | 178,400 | 269,800 |
position key pos:15030 · issuer key iss:1951 COM | ADD | +$618K | +326,874 | $27.5M | $28.1M | 840,600 | 1,167,474 |
position key pos:17319 · issuer key iss:652 COM | TRIM | −$10.1M | −69,486 | $38.1M | $28.0M | 358,971 | 289,485 |
position key pos:14904 · issuer key iss:1899 COM | ADD | −$3.5M | +113,094 | $30.6M | $27.1M | 726,740 | 839,834 |
position key pos:10581 · issuer key iss:2 COM | TRIM | +$4.3M | −27,575 | $22.6M | $26.8M | 272,700 | 245,125 |
position key pos:14223 · issuer key iss:941 COM | ADD | +$2.3M | +35,670 | $24.0M | $26.3M | 168,040 | 203,710 |
position key pos:11388 · issuer key iss:1133 COM | ADD | +$8.6M | +9,500 | $15.8M | $24.4M | 62,300 | 71,800 |
position key pos:12596 · issuer key iss:1481 COM | ADD | +$3.5M | +2,800 | $20.3M | $23.8M | 163,300 | 166,100 |
position key pos:12323 · issuer key iss:1544 COM | ADD | +$9.0M | +451,500 | $13.8M | $22.8M | 1,002,800 | 1,454,300 |
position key pos:13690 · issuer key iss:2116 COM | ADD | −$1.8M | +85,230 | $24.4M | $22.6M | 521,602 | 606,832 |
position key pos:12887 · issuer key iss:178 COM | ADD | +$2.3M | +19,300 | $20.0M | $22.3M | 83,000 | 102,300 |
position key pos:11922 · issuer key iss:291 COM | ADD | +$4.1M | +6,600 | $18.0M | $22.1M | 382,638 | 389,238 |
position key sid:sec:prov:9ad1f37e45baa2c0731276ae62c8a2e0 · issuer key cusip6:45245E COM | TRIM | −$2.2M | −75,161 | $24.1M | $21.9M | 652,300 | 577,139 |
position key pos:17938 · issuer key iss:1113 COM | ADD | +$970K | +173,400 | $20.6M | $21.6M | 993,900 | 1,167,300 |
position key pos:11116 · issuer key cusip6:02081G COM | ADD | −$286K | +907,893 | $21.0M | $20.8M | 1,000,400 | 1,908,293 |
position key pos:11929 · issuer key iss:1316 COM | ADD | +$7.3M | +6,610 | $13.4M | $20.7M | 356,400 | 363,010 |
position key pos:16788 · issuer key iss:1280 COM | ADD | +$407K | +13,280 | $20.3M | $20.7M | 784,500 | 797,780 |
position key pos:12938 · issuer key iss:120 COM | ADD | +$8.9M | +107,100 | $11.6M | $20.6M | 156,400 | 263,500 |
position key pos:10996 · issuer key iss:2155 COM | ADD | +$7.4M | +109,600 | $13.1M | $20.5M | 212,300 | 321,900 |
position key pos:15110 · issuer key iss:1112 COM | NEW | +$20.0M | +449,500 | $0 | $20.0M | — | 449,500 |
position key pos:14673 · issuer key iss:1879 COM | ADD | −$1.6M | +28,392 | $21.6M | $19.9M | 286,400 | 314,792 |
position key pos:17511 · issuer key iss:963 COM | NEW | +$19.9M | +653,413 | $0 | $19.9M | — | 653,413 |
position key pos:14792 · issuer key iss:845 COM | ADD | +$3.3M | +17,100 | $16.6M | $19.9M | 99,800 | 116,900 |
position key pos:15513 · issuer key iss:492 COM | ADD | +$2.5M | +131,100 | $17.4M | $19.9M | 960,912 | 1,092,012 |
position key pos:12194 · issuer key iss:1195 COM | ADD | +$9.0M | +58,800 | $10.8M | $19.8M | 253,900 | 312,700 |
position key pos:10505 · issuer key iss:1912 COM | ADD | +$10.7M | +85,100 | $9.1M | $19.7M | 508,100 | 593,200 |
position key pos:10360 · issuer key iss:443 COM | NEW | +$19.4M | +1,035,530 | $0 | $19.4M | — | 1,035,530 |
position key pos:15851 · issuer key iss:1426 COM | ADD | −$6.0M | +30,450 | $25.4M | $19.4M | 424,840 | 455,290 |
position key pos:14204 · issuer key iss:409 COM | ADD | +$5.6M | +193,600 | $13.7M | $19.3M | 586,970 | 780,570 |
position key pos:15672 · issuer key iss:1507 COM | ADD | −$5.6M | +57,769 | $24.3M | $18.7M | 336,860 | 394,629 |
position key pos:17530 · issuer key iss:1474 COM | TRIM | +$3.0M | −14,543 | $15.5M | $18.5M | 48,700 | 34,157 |
position key pos:12344 · issuer key iss:946 COM | ADD | −$2.8M | +36,304 | $21.2M | $18.4M | 119,700 | 156,004 |
position key pos:17354 · issuer key iss:308 COM | ADD | −$1.3M | +119,200 | $19.5M | $18.2M | 652,320 | 771,520 |
position key pos:12496 · issuer key iss:163 COM | ADD | +$7.8M | +351 | $10.3M | $18.1M | 32,971 | 33,322 |
position key sid:sec:prov:15b122a1959cdc720dffb69686bc9994 · issuer key cusip6:433313 COM | NEW | +$18.0M | +465,766 | $0 | $18.0M | — | 465,766 |
position key pos:18182 · issuer key iss:1303 COM | TRIM | −$3.3M | −91,050 | $21.0M | $17.7M | 302,700 | 211,650 |
position key pos:11418 · issuer key iss:103 COM | ADD | −$4.0M | +230,400 | $21.5M | $17.4M | 814,500 | 1,044,900 |
position key pos:12603 · issuer key iss:74 COM | ADD | +$2.3M | +219,100 | $14.8M | $17.0M | 747,500 | 966,600 |
position key pos:13106 · issuer key iss:14 COM | ADD | +$2.1M | +32,556 | $14.9M | $17.0M | 188,830 | 221,386 |
position key pos:11663 · issuer key iss:670 COM | NEW | +$16.9M | +665,400 | $0 | $16.9M | — | 665,400 |
position key pos:10670 · issuer key iss:1641 COM | ADD | −$9.1M | +62,600 | $25.9M | $16.8M | 198,770 | 261,370 |
position key pos:12239 · issuer key iss:1607 COM | ADD | +$1.3M | +6,541 | $15.4M | $16.7M | 76,900 | 83,441 |
position key pos:12723 · issuer key iss:1650 COM | NEW | +$16.6M | +187,570 | $0 | $16.6M | — | 187,570 |
position key pos:15656 · issuer key iss:378 COM | ADD | +$3.5M | +90,430 | $12.9M | $16.4M | 244,600 | 335,030 |
position key sid:sec:prov:02a4072384621d2b8e8f8b2b8586fe2c · issuer key cusip6:G8588X COM | ADD | +$1.2M | +245,900 | $15.2M | $16.4M | 1,268,500 | 1,514,400 |
position key sid:sec:prov:4f6675275ffbb7d8ae52b539305a5648 · issuer key cusip6:302301 COM | ADD | +$4.0M | +11,500 | $12.2M | $16.2M | 627,900 | 639,400 |
position key pos:13982 · issuer key iss:1108 COM | ADD | +$6.8M | +32,300 | $9.4M | $16.2M | 116,301 | 148,601 |
position key pos:10381 · issuer key iss:49 COM | ADD | +$7.6M | +9,483 | $8.3M | $15.9M | 39,700 | 49,183 |
position key pos:12749 · issuer key iss:2014 COM | ADD | +$3.4M | +86,183 | $12.4M | $15.8M | 266,000 | 352,183 |
position key pos:17169 · issuer key iss:2104 COM | ADD | +$4.3M | +5,063 | $11.5M | $15.8M | 25,200 | 30,263 |
position key pos:13344 · issuer key iss:2148 COM | ADD | +$2.4M | +5,834 | $12.9M | $15.3M | 312,800 | 318,634 |
position key sid:sec:prov:07df79d236bd2b44122da9ec24db0a18 · issuer key cusip6:71742Q COM | ADD | +$7.5M | +67,300 | $7.8M | $15.3M | 209,800 | 277,100 |
position key pos:16826 · issuer key iss:586 COM | ADD | +$7.8M | +72,400 | $7.5M | $15.3M | 151,900 | 224,300 |
position key sid:sec:prov:0339a5c20bb7c06dae4230f6939c6864 · issuer key cusip6:G037AX COM | TRIM | −$28.6M | −322,675 | $43.8M | $15.2M | 617,860 | 295,185 |
position key pos:16280 · issuer key iss:1210 COM | ADD | +$3.0M | +141,100 | $12.0M | $15.0M | 559,987 | 701,087 |
position key pos:17062 · issuer key iss:1174 COM | ADD | +$6.1M | +78,166 | $8.2M | $14.3M | 376,300 | 454,466 |
position key sid:sec:prov:e7b2a30be78670ddd0114593421f781f · issuer key cusip6:830940 COM | ADD | +$2.1M | +89,600 | $12.1M | $14.3M | 237,500 | 327,100 |
position key pos:13979 · issuer key iss:874 COM | ADD | +$6.3M | +102,350 | $7.9M | $14.2M | 117,580 | 219,930 |
position key pos:14778 · issuer key iss:1131 COM | ADD | +$2.7M | +42,900 | $11.4M | $14.0M | 329,200 | 372,100 |
position key sid:sec:prov:c72165ad5416fb78154dd267d5db39ec · issuer key cusip6:04206A COM | NEW | +$14.0M | +982,300 | $0 | $14.0M | — | 982,300 |
position key pos:12108 · issuer key iss:891 COM | ADD | +$956K | +25,061 | $13.0M | $13.9M | 141,580 | 166,641 |
position key pos:18167 · issuer key iss:1494 COM | ADD | +$4.9M | +17,600 | $9.0M | $13.9M | 947,900 | 965,500 |
position key pos:18165 · issuer key iss:2007 COM | ADD | −$1.7M | +104,040 | $15.6M | $13.9M | 767,020 | 871,060 |
position key pos:16048 · issuer key iss:1235 COM | ADD | −$399K | +136,467 | $14.2M | $13.8M | 607,800 | 744,267 |
Flags: no row carries a flag.
1–20 of the 100 changes on this page
1–100 of 191 changes
Mark-to-market only (no share change) · 10
Positions whose share count is identical in both quarters; the value changed with price, not with a decision.
position matched across quarters by exact reported CUSIP over a registry gap — producer-reconciled identity, never a name match identity_reconciled_by_cusip | the reported share count is unchanged across the pair; this build's data classified the change from its reported value; builds from 2026-09-10 on read it as NO CHANGE classified_by_value · EXIT = absent this quarter: disposed, delisted, under confidential treatment, or reported instead by an affiliated manager — the filing does not say which · change not classifiable: value undisclosed on one side of the quarter pair, or neither shares nor value can classify it · NO CHANGE = the share count is identical in both quarters; the value moved only with price, so the row is mark-to-market and never an ADD or a TRIM (NEW / ADD / TRIM / EXIT / NO CHANGE) · NO PRIOR = this filer has no comparable holdings list for the previous quarter on record — a first filing under this registration, or a quarter reported inside an affiliated manager's filing — so the position is not called a new stake | derived by Public Filings from the published aggregate; NULL means the source did not disclose a usable value — never zero | Prev value | Curr value | Prev shares | Curr shares | |
|---|---|---|---|---|---|---|---|
position key pos:13259 · issuer key iss:925 COM | NO CHANGE | +$77.8K | 0 | $1.1M | $1.2M | 24,000 | 24,000 |
position key pos:11825 · issuer key iss:1225 COM | NO CHANGE | −$302K | 0 | $1.3M | $987K | 2,665 | 2,665 |
position key pos:15142 · issuer key iss:89 COM | NO CHANGE | −$48.3K | 0 | $595K | $546K | 1,900 | 1,900 |
position key pos:17821 · issuer key iss:89 COM | NO CHANGE | −$43.6K | 0 | $508K | $465K | 1,620 | 1,620 |
position key pos:14206 · issuer key iss:1193 COM | NO CHANGE | −$47.0K | 0 | $378K | $331K | 662 | 662 |
position key pos:16392 · issuer key iss:1549 COM | NO CHANGE | −$23.8K | 0 | $349K | $325K | 1,450 | 1,450 |
position key pos:11237 · issuer key iss:1601 ETF | NO CHANGE | +$22.9K | 0 | $268K | $290K | 675 | 675 |
position key pos:15428 · issuer key iss:1955 PFD | NO CHANGE | −$12.8K | 0 | $273K | $260K | 225 | 225 |
position key pos:15892 · issuer key iss:7 COM | NO CHANGE | −$1.1K | 0 | $221K | $219K | 2,000 | 2,000 |
position key cusip:98401A106 · issuer key cusip6:98401A COM | NO CHANGE | $0 | 0 | $0 | $0 | 140,000 | 140,000 |
Flags: no row carries a flag.
Newest filing in this build: 2026-07-31. Per-row filing dates are on each receipt.
Changes compare every position with a security identifier, new and exited included; holdings without one are counted, not compared. methodology §13F ↗
Reported positions — 2026-03-31
1–100 of 179 issuers · $3.4B disclosed value over 180 rows · 0 undisclosed-value rowsViewThis build carries one quarter for this manager: 2026-03-31. Notable managers carry four published quarters, others two.
| This list carries reported issuer names and security identities, without a dated ticker mapping. Symbols are not inferred from names. | a position composed from a base filing plus NEW-HOLDINGS amendments keeps every source row here; the composition's latest filed date is the one shown served from this build's published holdings (derived from the filer's own reported rows); every row resolves to its filing | Share of total reported value, calculated only when the full position list has disclosed values. This is 13F long value, not total assets. | value undisclosed on the filing: retained and counted, excluded from sums, never shown as $0 | Shares | Wt |
|---|---|---|---|---|---|
| verified against the SEC company list on 2026-09-10 — a reviewed mapping row for this filed issuer name and class (never inferred) | Applied Optoelectronics Inc. · COM CUSIP — quarter ended 2026-03-31 filed filed 2026-05-15 +45d | $199M | 2,349,969 | 5.9% | |
| verified against the SEC company list on 2026-09-10 — a reviewed mapping row for this filed issuer name and class (never inferred) | Lumentum Hldgs, Inc. · COM CUSIP — quarter ended 2026-03-31 filed filed 2026-05-15 +45d | $187M | 266,222 | 5.5% | |
| — | Credo Technology Group · COM CUSIP — quarter ended 2026-03-31 filed filed 2026-05-15 +45d ticker not yet mapped | $95.9M | 1,021,968 | 2.8% | |
| — | DigitalOcean Holdings, Inc. · COM CUSIP — quarter ended 2026-03-31 filed filed 2026-05-15 +45d ticker not yet mapped | $79.6M | 927,505 | 2.3% | |
| — | SharkNinja, Inc. · COM CUSIP — quarter ended 2026-03-31 filed filed 2026-05-15 +45d ticker not yet mapped | $63.5M | 599,970 | 1.9% | |
| verified against the SEC company list on 2026-09-10 — a reviewed mapping row for this filed issuer name and class (never inferred) | Nova Ltd. · COM CUSIP — quarter ended 2026-03-31 filed filed 2026-05-15 +45d | $59.9M | 137,955 | 1.8% | |
| verified against the SEC company list on 2026-09-10 — a reviewed mapping row for this filed issuer name and class (never inferred) | Dana Inc. · COM CUSIP — quarter ended 2026-03-31 filed filed 2026-05-15 +45d | $54.2M | 1,611,500 | 1.6% | |
| — | BrightSpring Health Services · COM CUSIP — quarter ended 2026-03-31 filed filed 2026-05-15 +45d ticker not yet mapped | $49.4M | 1,158,970 | 1.5% | |
| — | Macom Technology Solutions · COM CUSIP — quarter ended 2026-03-31 filed filed 2026-05-15 +45d ticker not yet mapped | $47.9M | 215,886 | 1.4% | |
| verified against the SEC company list on 2026-09-10 — a reviewed mapping row for this filed issuer name and class (never inferred) | Rambus, Inc · COM CUSIP — quarter ended 2026-03-31 filed filed 2026-05-15 +45d | $45.3M | 526,316 | 1.3% | |
| verified against the SEC company list on 2026-09-10 — a reviewed mapping row for this filed issuer name and class (never inferred) | Clean Harbors, Inc. · COM CUSIP — quarter ended 2026-03-31 filed filed 2026-05-15 +45d | $41.4M | 144,355 | 1.2% | |
| verified against the SEC company list on 2026-09-10 — a reviewed mapping row for this filed issuer name and class (never inferred) | SiTime Corporation · COM CUSIP — quarter ended 2026-03-31 filed filed 2026-05-15 +45d | $41.2M | 119,281 | 1.2% | |
| — | Ultra Clean Holdings · COM CUSIP — quarter ended 2026-03-31 filed filed 2026-05-15 +45d ticker not yet mapped | $39.8M | 640,476 | 1.2% | |
| — | Everus Construction Group · COM CUSIP — quarter ended 2026-03-31 filed filed 2026-05-15 +45d ticker not yet mapped | $38.6M | 326,533 | 1.1% | |
| verified against the SEC company list on 2026-09-10 — a reviewed mapping row for this filed issuer name and class (never inferred) | Frontdoor, Inc. · COM CUSIP — quarter ended 2026-03-31 filed filed 2026-05-15 +45d | $38.0M | 717,960 | 1.1% | |
| verified against the SEC company list on 2026-09-10 — a reviewed mapping row for this filed issuer name and class (never inferred) | Carpenter Technology Corp. · COM CUSIP — quarter ended 2026-03-31 filed filed 2026-05-15 +45d | $37.2M | 94,433 | 1.1% | |
| verified against the SEC company list on 2026-09-10 — a reviewed mapping row for this filed issuer name and class (never inferred) | Skywest Inc · COM CUSIP — quarter ended 2026-03-31 filed filed 2026-05-15 +45d | $36.0M | 392,499 | 1.1% | |
| — | Lattice Semiconductor Corporat · COM CUSIP — quarter ended 2026-03-31 filed filed 2026-05-15 +45d ticker not yet mapped | $34.7M | 374,436 | 1.0% | |
| — | Globus Medical, Inc.-A · COM CUSIP — quarter ended 2026-03-31 filed filed 2026-05-15 +45d ticker not yet mapped | $33.8M | 392,200 | 1.0% | |
| — | Camtek, Ltd. · COM CUSIP M20791105 quarter ended 2026-03-31 filed filed 2026-05-15 +45d ticker not yet mapped | $33.8M | 222,780 | 1.0% | |
| — | Arcutis Biotherapeutics, Inc. · COM CUSIP 03969K108 quarter ended 2026-03-31 filed filed 2026-05-15 +45d ticker not yet mapped | $32.2M | 1,365,941 | 1.0% | |
| verified against the SEC company list on 2026-09-10 — a reviewed mapping row for this filed issuer name and class (never inferred) | Flowserve Corporation · COM CUSIP — quarter ended 2026-03-31 filed filed 2026-05-15 +45d | $32.0M | 434,681 | 0.9% | |
| — | Silicon Motion Techn ADR · COM CUSIP 82706C108 quarter ended 2026-03-31 filed filed 2026-05-15 +45d ticker not yet mapped | $31.7M | 282,550 | 0.9% | |
| — | Life Time Holdings, Inc. · COM CUSIP — quarter ended 2026-03-31 filed filed 2026-05-15 +45d ticker not yet mapped | $31.3M | 1,160,500 | 0.9% | |
| verified against the SEC company list on 2026-09-10 — a reviewed mapping row for this filed issuer name and class (never inferred) | Rush Street Interactive, Inc. · COM CUSIP — quarter ended 2026-03-31 filed filed 2026-05-15 +45d | $31.2M | 1,434,560 | 0.9% | |
| verified against the SEC company list on 2026-09-10 — a reviewed mapping row for this filed issuer name and class (never inferred) | FirstCash Holdings, Inc · COM CUSIP — quarter ended 2026-03-31 filed filed 2026-05-15 +45d | $31.1M | 165,665 | 0.9% | |
| — | Fastly, Inc. · COM CUSIP — quarter ended 2026-03-31 filed filed 2026-05-15 +45d ticker not yet mapped | $31.1M | 1,071,022 | 0.9% | |
| verified against the SEC company list on 2026-09-10 — a reviewed mapping row for this filed issuer name and class (never inferred) | Tutor Perini Corp. · COM CUSIP — quarter ended 2026-03-31 filed filed 2026-05-15 +45d | $30.4M | 393,900 | 0.9% | |
| — | Dutch Bros., Inc. · COM CUSIP — quarter ended 2026-03-31 filed filed 2026-05-15 +45d ticker not yet mapped | $30.3M | 598,493 | 0.9% | |
| — | Solaris Energy Infrastructur · COM CUSIP 83418M103 quarter ended 2026-03-31 filed filed 2026-05-15 +45d ticker not yet mapped | $30.1M | 531,889 | 0.9% | |
| — | Merit Medical System Inc · COM CUSIP — quarter ended 2026-03-31 filed filed 2026-05-15 +45d ticker not yet mapped | $29.2M | 424,209 | 0.9% | |
| verified against the SEC company list on 2026-09-10 — a reviewed mapping row for this filed issuer name and class (never inferred) | Federal Signal Corp. · COM CUSIP — quarter ended 2026-03-31 filed filed 2026-05-15 +45d | $28.9M | 267,634 | 0.9% | |
| — | American Superconductor · COM CUSIP — quarter ended 2026-03-31 filed filed 2026-05-15 +45d ticker not yet mapped | $28.8M | 849,900 | 0.8% | |
| — | Mercury Systems, Inc. · COM CUSIP — quarter ended 2026-03-31 filed filed 2026-05-15 +45d ticker not yet mapped | $28.5M | 391,023 | 0.8% | |
| verified against the SEC company list on 2026-09-10 — a reviewed mapping row for this filed issuer name and class (never inferred) | Arcosa, Inc. · COM CUSIP — quarter ended 2026-03-31 filed filed 2026-05-15 +45d | $28.4M | 267,700 | 0.8% | |
| verified against the SEC company list on 2026-09-10 — a reviewed mapping row for this filed issuer name and class (never inferred) | Osi Systems, Inc. · COM CUSIP — quarter ended 2026-03-31 filed filed 2026-05-15 +45d | $28.3M | 106,593 | 0.8% | |
| — | Core Natural Resources, Inc. · COM CUSIP — quarter ended 2026-03-31 filed filed 2026-05-15 +45d ticker not yet mapped | $28.3M | 269,800 | 0.8% | |
| — | Waystar Holding Corp. · COM CUSIP — quarter ended 2026-03-31 filed filed 2026-05-15 +45d ticker not yet mapped | $28.1M | 1,167,474 | 0.8% | |
| verified against the SEC company list on 2026-09-10 — a reviewed mapping row for this filed issuer name and class (never inferred) | Encompass Health Corporation · COM CUSIP — quarter ended 2026-03-31 filed filed 2026-05-15 +45d | $28.0M | 289,485 | 0.8% | |
| verified against the SEC company list on 2026-09-10 — a reviewed mapping row for this filed issuer name and class (never inferred) | Veracyte, Inc. · COM CUSIP — quarter ended 2026-03-31 filed filed 2026-05-15 +45d | $27.1M | 839,834 | 0.8% | |
| verified against the SEC company list on 2026-09-10 — a reviewed mapping row for this filed issuer name and class (never inferred) | AAR Corp. · COM CUSIP — quarter ended 2026-03-31 filed filed 2026-05-15 +45d | $26.8M | 245,125 | 0.8% | |
| — | ICU Medical, Inc. · COM CUSIP — quarter ended 2026-03-31 filed filed 2026-05-15 +45d ticker not yet mapped | $26.3M | 203,710 | 0.8% | |
| verified against the SEC company list on 2026-09-10 — a reviewed mapping row for this filed issuer name and class (never inferred) | Littelfuse, Inc. · COM CUSIP — quarter ended 2026-03-31 filed filed 2026-05-15 +45d | $24.4M | 71,800 | 0.7% | |
| — | Primoris Services Corp. · COM CUSIP — quarter ended 2026-03-31 filed filed 2026-05-15 +45d ticker not yet mapped | $23.8M | 166,100 | 0.7% | |
| verified against the SEC company list on 2026-09-10 — a reviewed mapping row for this filed issuer name and class (never inferred) | Remitly Global, Inc. · COM CUSIP — quarter ended 2026-03-31 filed filed 2026-05-15 +45d | $22.8M | 1,454,300 | 0.7% | |
| — | Genpact Ltd. · COM CUSIP — quarter ended 2026-03-31 filed filed 2026-05-15 +45d ticker not yet mapped | $22.6M | 606,832 | 0.7% | |
| verified against the SEC company list on 2026-09-10 — a reviewed mapping row for this filed issuer name and class (never inferred) | Assurant, Inc. · COM CUSIP — quarter ended 2026-03-31 filed filed 2026-05-15 +45d | $22.3M | 102,300 | 0.7% | |
| verified against the SEC company list on 2026-09-10 — a reviewed mapping row for this filed issuer name and class (never inferred) | Blue Bird Corporation · COM CUSIP — quarter ended 2026-03-31 filed filed 2026-05-15 +45d | $22.1M | 389,238 | 0.7% | |
| — | Imax Corp. · COM CUSIP 45245E109 quarter ended 2026-03-31 filed filed 2026-05-15 +45d ticker not yet mapped | $21.9M | 577,139 | 0.6% | |
| — | Levi Strauss & Co. · COM CUSIP — quarter ended 2026-03-31 filed filed 2026-05-15 +45d ticker not yet mapped | $21.6M | 1,167,300 | 0.6% | |
| — | Alphatec Hldgs Inc. · COM CUSIP — quarter ended 2026-03-31 filed filed 2026-05-15 +45d ticker not yet mapped | $20.8M | 1,908,293 | 0.6% | |
| verified against the SEC company list on 2026-09-10 — a reviewed mapping row for this filed issuer name and class (never inferred) | nLIGHT Inc. · COM CUSIP — quarter ended 2026-03-31 filed filed 2026-05-15 +45d | $20.7M | 363,010 | 0.6% | |
| — | National Vision Holdings, Inc. · COM CUSIP — quarter ended 2026-03-31 filed filed 2026-05-15 +45d ticker not yet mapped | $20.7M | 797,780 | 0.6% | |
| verified against the SEC company list on 2026-09-10 — a reviewed mapping row for this filed issuer name and class (never inferred) | Ameris Bancorp · COM CUSIP — quarter ended 2026-03-31 filed filed 2026-05-15 +45d | $20.6M | 263,500 | 0.6% | |
| — | LivaNova Plc · COM CUSIP — quarter ended 2026-03-31 filed filed 2026-05-15 +45d ticker not yet mapped | $20.5M | 321,900 | 0.6% | |
| verified against the SEC company list on 2026-09-10 — a reviewed mapping row for this filed issuer name and class (never inferred) | Leonardo DRS, Inc. · COM CUSIP — quarter ended 2026-03-31 filed filed 2026-05-15 +45d | $20.0M | 449,500 | 0.6% | |
| verified against the SEC company list on 2026-09-10 — a reviewed mapping row for this filed issuer name and class (never inferred) | Urban Outfitters, Inc. · COM CUSIP — quarter ended 2026-03-31 filed filed 2026-05-15 +45d | $19.9M | 314,792 | 0.6% | |
| — | Indivior Plc · COM CUSIP — quarter ended 2026-03-31 filed filed 2026-05-15 +45d ticker not yet mapped | $19.9M | 653,413 | 0.6% | |
| — | Grand Canyon Education, Inc. · COM CUSIP — quarter ended 2026-03-31 filed filed 2026-05-15 +45d ticker not yet mapped | $19.9M | 116,900 | 0.6% | |
| verified against the SEC company list on 2026-09-10 — a reviewed mapping row for this filed issuer name and class (never inferred) | Vistance Networks, Inc. · COM CUSIP — quarter ended 2026-03-31 filed filed 2026-05-15 +45d | $19.9M | 1,092,012 | 0.6% | |
| — | Matador Resources Company · COM CUSIP — quarter ended 2026-03-31 filed filed 2026-05-15 +45d ticker not yet mapped | $19.8M | 312,700 | 0.6% | |
| verified against the SEC company list on 2026-09-10 — a reviewed mapping row for this filed issuer name and class (never inferred) | Viavi Solutions, Inc. · COM CUSIP — quarter ended 2026-03-31 filed filed 2026-05-15 +45d | $19.7M | 593,200 | 0.6% | |
| — | Chime Financial Inc. · COM CUSIP — quarter ended 2026-03-31 filed filed 2026-05-15 +45d ticker not yet mapped | $19.4M | 1,035,530 | 0.6% | |
| verified against the SEC company list on 2026-09-10 — a reviewed mapping row for this filed issuer name and class (never inferred) | Pegasystems Inc. · COM CUSIP — quarter ended 2026-03-31 filed filed 2026-05-15 +45d | $19.4M | 455,290 | 0.6% | |
| verified against the SEC company list on 2026-09-10 — a reviewed mapping row for this filed issuer name and class (never inferred) | Catalyst Pharmaceuticals, Inc. · COM CUSIP — quarter ended 2026-03-31 filed filed 2026-05-15 +45d | $19.3M | 780,570 | 0.6% | |
| — | Q2 Holdings, Inc. · COM CUSIP — quarter ended 2026-03-31 filed filed 2026-05-15 +45d ticker not yet mapped | $18.7M | 394,629 | 0.6% | |
| — | Powell Industries Inc. · COM CUSIP — quarter ended 2026-03-31 filed filed 2026-05-15 +45d ticker not yet mapped | $18.5M | 34,157 | 0.5% | |
| verified against the SEC company list on 2026-09-10 — a reviewed mapping row for this filed issuer name and class (never inferred) | Irhythm Holdings, Inc. · COM CUSIP — quarter ended 2026-03-31 filed filed 2026-05-15 +45d | $18.4M | 156,004 | 0.5% | |
| — | Box, Inc. · COM CUSIP — quarter ended 2026-03-31 filed filed 2026-05-15 +45d ticker not yet mapped | $18.2M | 771,520 | 0.5% | |
| verified against the SEC company list on 2026-09-10 — a reviewed mapping row for this filed issuer name and class (never inferred) | Argan, Inc · COM CUSIP — quarter ended 2026-03-31 filed filed 2026-05-15 +45d | $18.1M | 33,322 | 0.5% | |
| — | Hinge Health, Inc. · COM CUSIP 433313103 quarter ended 2026-03-31 filed filed 2026-05-15 +45d ticker not yet mapped | $18.0M | 465,766 | 0.5% | |
| — | New York Times Co. Cl A · COM CUSIP — quarter ended 2026-03-31 filed filed 2026-05-15 +45d ticker not yet mapped | $17.7M | 211,650 | 0.5% | |
| — | American Eagle Outfitters · COM CUSIP — quarter ended 2026-03-31 filed filed 2026-05-15 +45d ticker not yet mapped | $17.4M | 1,044,900 | 0.5% | |
| — | Alighnment Healthcare, Inc. · COM CUSIP — quarter ended 2026-03-31 filed filed 2026-05-15 +45d ticker not yet mapped | $17.0M | 966,600 | 0.5% | |
| verified against the SEC company list on 2026-09-10 — a reviewed mapping row for this filed issuer name and class (never inferred) | ANI Pharmaceuticals, Inc. · COM CUSIP — quarter ended 2026-03-31 filed filed 2026-05-15 +45d | $17.0M | 221,386 | 0.5% | |
| verified against the SEC company list on 2026-09-10 — a reviewed mapping row for this filed issuer name and class (never inferred) | Envista Holdings Corp. · COM CUSIP — quarter ended 2026-03-31 filed filed 2026-05-15 +45d | $16.9M | 665,400 | 0.5% | |
| — | Genedx Holdings Corp. · COM CUSIP — quarter ended 2026-03-31 filed filed 2026-05-15 +45d ticker not yet mapped | $16.8M | 261,370 | 0.5% | |
| verified against the SEC company list on 2026-09-10 — a reviewed mapping row for this filed issuer name and class (never inferred) | SPX Technologies, Inc. · COM CUSIP — quarter ended 2026-03-31 filed filed 2026-05-15 +45d | $16.7M | 83,441 | 0.5% | |
| — | Shake Shack, Inc. · COM CUSIP — quarter ended 2026-03-31 filed filed 2026-05-15 +45d ticker not yet mapped | $16.6M | 187,570 | 0.5% | |
| verified against the SEC company list on 2026-09-10 — a reviewed mapping row for this filed issuer name and class (never inferred) | Calix, Inc. · COM CUSIP — quarter ended 2026-03-31 filed filed 2026-05-15 +45d | $16.4M | 335,030 | 0.5% | |
| — | Super Group SGHC Ltd. · COM CUSIP G8588X103 quarter ended 2026-03-31 filed filed 2026-05-15 +45d ticker not yet mapped | $16.4M | 1,514,400 | 0.5% | |
| — | EZCorp, Inc. · COM CUSIP 302301106 quarter ended 2026-03-31 filed filed 2026-05-15 +45d ticker not yet mapped | $16.2M | 639,400 | 0.5% | |
| verified against the SEC company list on 2026-09-10 — a reviewed mapping row for this filed issuer name and class (never inferred) | LeMaitre Vascular, Inc. · COM CUSIP — quarter ended 2026-03-31 filed filed 2026-05-15 +45d | $16.2M | 148,601 | 0.5% | |
| — | Advanced Energy Industry, Inc. · COM CUSIP — quarter ended 2026-03-31 filed filed 2026-05-15 +45d ticker not yet mapped | $15.9M | 49,183 | 0.5% | |
| — | Zurn Elkay Water Solutions Cor · COM CUSIP — quarter ended 2026-03-31 filed filed 2026-05-15 +45d ticker not yet mapped | $15.8M | 352,183 | 0.5% | |
| — | Fabrinet · COM CUSIP — quarter ended 2026-03-31 filed filed 2026-05-15 +45d ticker not yet mapped | $15.8M | 30,263 | 0.5% | |
| — | Kiniksa Pharmaceuticals, Ltd. · COM CUSIP — quarter ended 2026-03-31 filed filed 2026-05-15 +45d ticker not yet mapped | $15.3M | 318,634 | 0.5% | |
| — | Phibro Animal Health Corp · COM CUSIP 71742Q106 quarter ended 2026-03-31 filed filed 2026-05-15 +45d ticker not yet mapped | $15.3M | 277,100 | 0.5% | |
| verified against the SEC company list on 2026-09-10 — a reviewed mapping row for this filed issuer name and class (never inferred) | Diodes, Inc. · COM CUSIP — quarter ended 2026-03-31 filed filed 2026-05-15 +45d | $15.3M | 224,300 | 0.5% | |
| — | Ambarella, Inc. · COM CUSIP G037AX101 quarter ended 2026-03-31 filed filed 2026-05-15 +45d ticker not yet mapped | $15.2M | 295,185 | 0.4% | |
| verified against the SEC company list on 2026-09-10 — a reviewed mapping row for this filed issuer name and class (never inferred) | Pediatrix Medical Group, Inc. · COM CUSIP — quarter ended 2026-03-31 filed filed 2026-05-15 +45d | $15.0M | 701,087 | 0.4% | |
| — | Magnolia Oil & Gas Corp. · COM CUSIP — quarter ended 2026-03-31 filed filed 2026-05-15 +45d ticker not yet mapped | $14.3M | 454,466 | 0.4% | |
| — | Skyward Specialty Ins Group · COM CUSIP 830940102 quarter ended 2026-03-31 filed filed 2026-05-15 +45d ticker not yet mapped | $14.3M | 327,100 | 0.4% | |
| verified against the SEC company list on 2026-09-10 — a reviewed mapping row for this filed issuer name and class (never inferred) | Halozyme Therapeutics, Inc. · COM CUSIP — quarter ended 2026-03-31 filed filed 2026-05-15 +45d | $14.2M | 219,930 | 0.4% | |
| — | Liquidia Corp. · COM CUSIP — quarter ended 2026-03-31 filed filed 2026-05-15 +45d ticker not yet mapped | $14.0M | 372,100 | 0.4% | |
| — | Arlo Technologies, Inc. · COM CUSIP 04206A101 quarter ended 2026-03-31 filed filed 2026-05-15 +45d ticker not yet mapped | $14.0M | 982,300 | 0.4% | |
| verified against the SEC company list on 2026-09-10 — a reviewed mapping row for this filed issuer name and class (never inferred) | HealthEquity Inc. · COM CUSIP — quarter ended 2026-03-31 filed filed 2026-05-15 +45d | $13.9M | 166,641 | 0.4% | |
| — | ProPetro Holding Corp. · COM CUSIP — quarter ended 2026-03-31 filed filed 2026-05-15 +45d ticker not yet mapped | $13.9M | 965,500 | 0.4% | |
| — | Zeta Global Holdings Corp. · COM CUSIP — quarter ended 2026-03-31 filed filed 2026-05-15 +45d ticker not yet mapped | $13.9M | 871,060 | 0.4% | |
| — | Mirion Technologies, Inc. · COM CUSIP — quarter ended 2026-03-31 filed filed 2026-05-15 +45d ticker not yet mapped | $13.8M | 744,267 | 0.4% |
1–20 of the 100 issuers on this page
Change kind and share change are in Position changes above; Congress overlap is planned.
1–100 of 179 issuers · page 1 of 2
One line per issuer, largest first; a row with no issuer key stands on its own line. Open a line for its rows as this filer reported them. The list holds every row this filer reported for the quarter. Issuer totals on the holders pages count each manager's own report once; that never removes a row here. how positions are grouped ↗
Book shape
2026-03-31 · concentration · vs tracked median · tick = median- Top-25 concentration
- 41.8%below median 80.0%
- Concentration index
- 142 bpsbelow median 446 bps
- Positions with value
- 180 / 180median book 97.5 positions
Concentration uses reported 13F long value, not total assets. The index is withheld when any position lacks a value. Medians are over the 8,748 tracked filers with a 2026-03-31 book; the index median over the 8,662 with a complete book.
holdings whose <value> did not parse — retained and counted, never zero-filled: 0 · : 41.8% · integer Herfindahl–Hirschman index in basis points over disclosed position values: 142 · QoQ moves: 201
Filing history
AVAILABLE QUARTERS| Period | Source |
|---|---|
| 2026-03-31 | EDGAR ↗ |
PLANNED sector rotation · Congress overlap · signals for this filer
Complete source filings on SEC EDGAR
The complete filing on EDGAR.
The position list above is served from the published Public Filings build, each position as this filer reported it; where the page cannot embed every reported row, the list says how many it leaves out. This block is provenance, not a substitute: the filing itself is the record, and it is one click away. Public Filings decided on 2026-08-01 to serve this list from its published build; filings newer than this build are on EDGAR.
Open OBERWEIS ASSET MANAGEMENT INC/'s 13F filings on SEC EDGAR ↗Notes on this data
Share changes
Compare consecutive quarters
Position changes retain the producer’s classification and comparability flags. Share counts and reported values describe different changes.
Coverage
A snapshot, not current holdings
Use the quarter selector to inspect available periods. Unknown values stay unknown and each table states its coverage.
A 13F is a quarterly, long-only snapshot filed up to 45 days late — not current holdings. what a 13F covers ↗
13F reports cover LONG positions in Section 13(f) securities (US exchange-traded equities plus reportable options, warrants, certain convertibles) held by managers with at least $100M in such securities — so managers below that threshold are absent entirely. No short positions, no cash, no non-13(f) assets — not a full portfolio, and not a census of institutional ownership.
Positions are quarter-end snapshots filed up to 45 days late — not current holdings. A position may have been changed or closed before you ever see it, and is older still by however long ago that quarter ended.
Values are the manager's stated market value at quarter-end in era-dependent units (whole dollars for form versions effective 2023-01-03 onward, thousands before), normalized here to whole dollars with unit_basis carried on every record.
Affiliated managers may report the same position (otherManager), so one position can appear under more than one filer.
Positions under confidential treatment may be omitted until a later amendment discloses them.
These are disclosures, not investment advice (ARCHITECTURE.md §5.2 / M2-CONTRACT §5).