0001144204-11-029726.txt : 20110516 0001144204-11-029726.hdr.sgml : 20110516 20110516134258 ACCESSION NUMBER: 0001144204-11-029726 CONFORMED SUBMISSION TYPE: 13F-HR PUBLIC DOCUMENT COUNT: 1 CONFORMED PERIOD OF REPORT: 20110331 FILED AS OF DATE: 20110516 DATE AS OF CHANGE: 20110516 EFFECTIVENESS DATE: 20110516 FILER: COMPANY DATA: COMPANY CONFORMED NAME: OBERWEIS ASSET MANAGEMENT INC/ CENTRAL INDEX KEY: 0000937886 IRS NUMBER: 364106772 STATE OF INCORPORATION: MA FISCAL YEAR END: 1231 FILING VALUES: FORM TYPE: 13F-HR SEC ACT: 1934 Act SEC FILE NUMBER: 028-04688 FILM NUMBER: 11845313 BUSINESS ADDRESS: STREET 1: 3333 WARRENVILLE ROAD STREET 2: SUITE 500 CITY: LISLE STATE: IL ZIP: 60532 BUSINESS PHONE: 6305772300 MAIL ADDRESS: STREET 1: 3333 WARRENVILLE ROAD STREET 2: SUITE 500 CITY: LISLE STATE: IL ZIP: 60532 13F-HR 1 v222933_13fhr.txt FORM 13F UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 Form 13F Form 13F COVER PAGE Report for the Calendar Year or Quarter Ended: March 31, 2011 Check here if Amendment [ ]; Amendment Number: ____________ This Amendment (Check only one.): [ ] is a restatement. [ ] adds new holdings entries. Institutional Investment Manager Filing this Report: Name: Oberweis Asset Management, Inc. Address: 3333 Warrenville Road, Suite 500 Lisle, IL 60532 Form 13F File Number: 28- 4688 The institutional investment manager filing this report and the person by whom it is signed hereby represent that the person signing the report is authorized to submit it, that all information contained herein is true, correct and complete, and that it is understood that all required items, statements, schedules, lists, and tables, are considered integral parts of this form. Person signing this Report on Behalf of Reporting Manager: Name: Patrick B. Joyce Title: Executive Vice President Phone: (800) 323-6166 Signature, Place, and Date of Signing: /s/ Patrick B. Joyce Lisle, IL May 16, 2011 ------------------------ ------------------------ ------------------- [Signature] [City, State] [Date] Report Type (Check only one.): [X] 13F HOLDINGS REPORT. (Check here if all holdings of this reporting manager are reported in this report.) [ ] 13F NOTICE. (Check here if no holdings reported are in this report, and all holdings are reported by other reporting manager(s).) [ ] 13F COMBINATION REPORT. (Check here if a portion of the holdings for this reporting manager are reported in this report and a portion are reported by other reporting manager(s).) FORM 13F SUMMARY PAGE Report Summary: Number of other Included Managers: _____ Form 13F Information Table Entry Total: 205 Data Records Form 13F Information Table Value Total: $478,072 (thousands) List of Other Included Managers: Provide a numbered list of the name(s) and Form 13F file number (s) of all institutional investment managers with respect to which this report is filed, other than the manger filing this report. [If there are no entries in this list, state "NONE" and omit the column headings and list entries.] NONE

FORM 13F INFORMATION TABLE VALUE SHARES/ SH/ PUT/ INVSTMT OTHER VOTING AUTHORITY NAME OF ISSUER TITLE OF CLASS CUSIP (x$1000) PRN AMT PRN CALL DSCRETN MANAGERS SOLE SHARED NONE ------------------------------ ---------------- --------- -------- -------- --- ---- ------- ------------ -------- -------- -------- 3-D Systems Corporation com 88554D205 2577 53100 SH Sole 39000 14100 3SBio Inc ADR com 88575Y105 3577 206900 SH Sole 206900 51Job Inc. ADR com 316827104 5171 80880 SH Sole 74200 6680 ADA-ES, Inc. com 005208103 3496 159980 SH Sole 143300 16680 Acacia Research-Acacia Tech com 003881307 19457 566435 SH Sole 459960 106475 Acme Packet, Inc. com 004764106 2331 32850 SH Sole 16790 16060 Active Power, Inc. com 00504W100 6205 2117750 SH Sole 1873400 244350 AdCare Health Systems, Inc. com 00650W300 1323 284455 SH Sole 284455 Adept Technology, Inc. com 006854202 429 93200 SH Sole 93200 Advanced Energy Industry, Inc. com 007973100 793 48500 SH Sole 35600 12900 Akorn Inc. com 009728106 58 10000 SH Sole 10000 Align Technology, Inc. com 016255101 731 35700 SH Sole 26500 9200 Alliance Fiber Optic Products com 018680306 1822 163300 SH Sole 163300 Allied Motion Technologies com 019330109 353 50000 SH Sole 50000 Almost Family, Inc. com 020409108 1713 45500 SH Sole 45500 Ambow Education Holding ADR com 02322P101 1880 237100 SH Sole 237100 Ameresco, Inc. com 02361E108 778 55000 SH Sole 40700 14300 American Superconductor com 030111108 1576 63350 SH Sole 47250 16100 American Xtal Technology com 00246W103 553 77100 SH Sole 77100 Amerigon, Inc. com 03070L300 11639 762230 SH Sole 660000 102230 Amgen, Inc. com 031162100 207 3875 SH Sole 3875 Amtech Systems, Inc. com 032332504 1300 51500 SH Sole 51500 Ancestry.com, Inc. com 032803108 837 23600 SH Sole 17500 6100 Aruba Networks Inc. com 043176106 6157 181930 SH Sole 96500 85430 Autonavi Holdings Ltd. ADR com 05330F106 1718 97000 SH Sole 97000 Axcelis Technologies com 054540109 1848 697400 SH Sole 697400 BHP Billiton Ltd. ADR com 088606108 430 4488 SH Sole 4488 Baidu Inc. Spon ADR com 056752108 469 3400 SH Sole 3400 Bank of New York Mellon Corp. com 064058100 230 7711 SH Sole 7711 Barnwell Industries, Inc. com 068221100 463 63900 SH Sole 63900 Barrett Bill Corp. com 06846N104 922 23100 SH Sole 17100 6000 Blackboard com 091935502 1863 51400 SH Sole 37700 13700 Body Central Corp. com 09689U102 4418 190200 SH Sole 190200 Bofi Holding, Inc. com 05566U108 4867 313583 SH Sole 278033 35550 Brooks Automation Inc. com 114340102 1210 88100 SH Sole 65000 23100 Bryn Mawr Bank Corp. com 117665109 1894 92100 SH Sole 92100 Bsquare Corp. com 11776U300 3533 494880 SH Sole 386400 108480 CPI Aerostructures, Inc. com 125919308 2442 160635 SH Sole 160635 Cai International, Inc. com 12477X106 1151 44500 SH Sole 44500 Cardinal Finl Corp. com 14149F109 2088 179100 SH Sole 177400 1700 Carrizo Oil & Gas, Inc. com 144577103 6571 177918 SH Sole 124764 53154 Cavium Networks, Inc. com 14965A101 431 9600 SH Sole 7100 2500 Ceragon Networks ADR com M22013102 2046 169400 SH Sole 169400 Changyou.com Ltd. ADR com 15911M107 1834 57075 SH Sole 57075 Charm Communications, Inc. com 16112R101 3212 323600 SH Sole 323600 Chase Corp. com 16150R104 1161 62500 SH Sole 62500 China Kanghui Holding ADR com 16890V100 1984 113290 SH Sole 112300 990 China Ming Yang Wind Pow ADS com 16951c108 2733 265100 SH Sole 265100 China XD Plastics Co. Ltd com 16948F107 1445 277300 SH Sole 277300 Cirrus Logic com 172755100 620 29500 SH Sole 24700 4800 Citigroup Incorporated com 172967424 77 17420 SH Sole 17420 ClearOne Communications, Inc. com 185060100 772 114500 SH Sole 114500 Coca-Cola com 191216100 270 4076 SH Sole 4076 Cognex Corp. com 192422103 3588 126995 SH Sole 76660 50335 Cohu, Inc. com 192576106 697 45400 SH Sole 45400 Concord Medical Spon ADR com 206277105 1900 336300 SH Sole 336300 Conmed Healthcare Management com 20741M103 1004 307000 SH Sole 307000 Constant Contact, Inc. com 210313102 3388 97070 SH Sole 54400 42670 DG Fastchannel, Inc. com 23326R109 1577 49000 SH Sole 36000 13000 Danvers Bancorp, Inc. com 236442109 872 40700 SH Sole 40500 200 Datalink Corp. com 237934104 1234 192800 SH Sole 192800 Digimarc Corp. com 25381B101 2113 73100 SH Sole 73100 Dusa Pharmaceuticals com 266898105 2232 429300 SH Sole 429300 EPlus, Inc. com 294268107 1110 41700 SH Sole 41700 Egain Communications Corp. com 28225C806 349 124800 SH Sole 124800 Electro Rent Corp. com 285218103 1108 64500 SH Sole 64500 Endologix, Inc. com 29266S106 3097 456800 SH Sole 456800 Entropic Communications, Inc. com 29384R105 547 64700 SH Sole 64700 Exfo Inc. com 302046107 1993 182300 SH Sole 137600 44700 Exlservice Holdings com 302081104 1868 88300 SH Sole 65100 23200 Exxon Mobil Corp. com 30231G102 227 2693 SH Sole 2693 Faro Technologies, Inc. com 311642102 3306 82650 SH Sole 59300 23350 First Savings Financial Group, com 33621E109 589 38500 SH Sole 38500 G III Apparel Group Ltd. com 36237H101 12067 321200 SH Sole 287200 34000 GLG Life Tech Corporation com 361793201 1074 102000 SH Sole 102000 GSE Systems com 36227K106 614 271600 SH Sole 271600 GSI Technology, Inc. com 36241U106 2273 250000 SH Sole 250000 General Electric Co. com 369604103 342 17052 SH Sole 17052 Geoeye, Inc. com 37250W108 798 19200 SH Sole 14100 5100 Georesources, Inc. com 372476101 7311 233800 SH Sole 232600 1200 Global Education & Tech ADR com 37951A108 929 151500 SH Sole 147100 4400 Globecom Systems Inc com 37956X103 1565 126900 SH Sole 126900 Green Mtn Coffee com 393122106 5865 90770 SH Sole 57040 33730 Gulfport Energy Corp. com 402635304 5102 141200 SH Sole 102700 38500 HMS Holdings Corp. com 40425J101 2394 29250 SH Sole 20400 8850 Hardinge, Inc. com 412324303 722 52700 SH Sole 52700 Hi-Tech Pharmacal com 42840B101 2768 137500 SH Sole 137500 Higher One Holdings, Inc. com 42983D104 4135 286180 SH Sole 209300 76880 Home Inns & Hotels Mgmt com 43713W107 5857 148025 SH Sole 124980 23045 Hurco Companies, Inc. com 447324104 808 26500 SH Sole 26500 ICF International, Inc. com 44925C103 904 44000 SH Sole 44000 II-VI Inc. com 902104108 2234 44900 SH Sole 33600 11300 IPC The Hospitalist Co. com 44984A105 3673 80880 SH Sole 80880 IPG Photonics Corp com 44980X109 4924 85360 SH Sole 47700 37660 IROBOT Corp com 462726100 4170 126780 SH Sole 75090 51690 Igate Corp. com 45169U105 1350 71900 SH Sole 52400 19500 Illumina, Inc. com 452327109 388 5540 SH Sole 5540 Imax Corp. com 45245E109 12448 389255 SH Sole 270290 118965 Impax Laboratories, Inc. com 45256B101 4128 162210 SH Sole 95170 67040 Imris, Inc. com 45322N105 5990 825130 SH Sole 688600 136530 Intel Corporation com 458140100 234 11619 SH Sole 11619 Interactive Intelligence Inc. com 45839M103 4046 104510 SH Sole 66200 38310 Ista Pharmaceuticals, Inc. com 45031X204 6188 611500 SH Sole 611500 Ixia com 45071R109 2083 131200 SH Sole 96800 34400 Ixys Corporation com 46600W106 3230 240500 SH Sole 240500 JDS Uniphase Corp. com 46612J507 216 10380 SH Sole 10380 Jinkosolar Holding Co. ADR com 47759T100 3019 111800 SH Sole 108980 2820 Johnson & Johnson com 478160104 286 4823 SH Sole 4823 KSW, Inc. com 48268R106 409 116000 SH Sole 116000 Kadant Inc. com 48282T104 2946 112500 SH Sole 112500 Kemet Corporation com 488360207 6987 471173 SH Sole 393452 77721 Kraton Performance Polymers com 50077C106 1103 28840 SH Sole 22240 6600 Kvh Industries, Inc. com 482738101 2852 188600 SH Sole 188600 LGL Group, Inc. com 50186A108 1983 142800 SH Sole 142800 LML Payment Systems, Inc. com 50208P109 1237 426500 SH Sole 426500 LSB Industries, Inc. com 502160104 1938 48900 SH Sole 35800 13100 La Barge com 502470107 1276 72100 SH Sole 72100 Lecroy Corp. com 52324W109 2840 212400 SH Sole 212400 Lihua International, Inc. com 532352101 1000 113900 SH Sole 113900 Liveperson, Inc. com 538146101 1340 106000 SH Sole 106000 Logmein, Inc. com 54142L109 4268 101240 SH Sole 61930 39310 Longtop Financial Techno ADR com 54318P108 2707 86170 SH Sole 80400 5770 MWI Vetrinary Supply com 55402X105 1936 24000 SH Sole 17700 6300 Magic Software Enterprises Ltd com 559166103 486 64400 SH Sole 64400 Manitex International, Inc. com 563420108 1078 196000 SH Sole 196000 Mastech Holdings, Inc. com 57633B100 90 19400 SH Sole 19400 Materion Corp. com 576690101 4312 105690 SH Sole 63300 42390 Mcdonald's com 580135101 374 4922 SH Sole 4922 Measurement Specialties Inc. com 583421102 4778 140460 SH Sole 120300 20160 Mediamind Techologies, Inc. com 58449C100 1529 110700 SH Sole 110700 Medidata Solutions, Inc. com 58471A105 8732 341500 SH Sole 304100 37400 Microsoft Corp. com 594918104 419 16517 SH Sole 16517 Mips Technologies, Inc. com 604567107 538 51300 SH Sole 27000 24300 Mistras Group, Inc. com 60649T107 5670 329460 SH Sole 281100 48360 Mitek Systems, Inc. com 606710200 1429 352730 SH Sole 346400 6330 Momenta Pharmaceuticals Inc. com 60877T100 927 58500 SH Sole 43800 14700 NN, Inc. com 629337106 2414 132200 SH Sole 132200 Nanometrics, Inc. com 630077105 2323 128390 SH Sole 124200 4190 National American University H com 63245Q105 1602 225900 SH Sole 225900 Natus Med, Inc. com 639050103 1033 61460 SH Sole 43600 17860 Netease.Com, Inc. com 64110W102 3763 76000 SH Sole 76000 Netgear, Inc. com 64111Q104 1145 35300 SH Sole 25800 9500 Netlogic Microsystems com 64118B100 409 9740 SH Sole 6900 2840 Newport Corp. com 651824104 1557 87300 SH Sole 64100 23200 Northern Oil & Gas, Inc. com 665531109 3284 123000 SH Sole 90300 32700 Omnivision Technologies, Inc. com 682128103 433 12200 SH Sole 8900 3300 Opentable, Inc. com 68372A104 7649 71920 SH Sole 50180 21740 Oplink Communications, Inc. com 68375Q403 2222 114000 SH Sole 114000 Optical Cable Corp. com 683827208 913 186400 SH Sole 186400 Orbit\FR Inc. com 685929101 164 56540 SH Sole 56540 Panhandle Oil & Gas Inc. com 698477106 2238 70700 SH Sole 70700 Perceptron Inc. com 71361F100 1038 163500 SH Sole 163500 Power-One, Inc. com 73930R102 1306 149310 SH Sole 101450 47860 Primo Water Corp. com 74165N105 1889 153300 SH Sole 153300 QKL Stores, Inc. com 74732Y105 1239 469200 SH Sole 469200 RDA Microelectronics com 749394102 1830 127800 SH Sole 127800 Raven Inds, Inc. com 754212108 2094 34100 SH Sole 25100 9000 Real Goods Solar Inc. - Class com 75601N104 381 143700 SH Sole 143700 RealD, Inc. com 75604L105 1735 63400 SH Sole 46500 16900 Realpage, Inc. com 75606N109 3103 111894 SH Sole 65764 46130 Richmont Mines, Inc. com 76547T106 2234 335900 SH Sole 333700 2200 Rightnow Tech Inc. com 76657r106 2873 91750 SH Sole 62700 29050 Rubicon Technology, Inc. com 78112T107 3528 127440 SH Sole 78000 49440 Rue21, Inc. com 781295100 2139 74400 SH Sole 54900 19500 SXC Health Solutions Corp. com 78505P100 7554 137850 SH Sole 106900 30950 Senesco Technologies, Inc com 817208408 15 50000 SH Sole 50000 Silicom Ltd. com M84116108 1070 58200 SH Sole 58200 Silicon Graphics International com 82706L108 1736 81100 SH Sole 81100 Silicon Image, Inc. com 82705T102 392 43700 SH Sole 32000 11700 Sina Corp Ord com G81477104 3746 35000 SH Sole 34700 300 Soufun Holdings Ltd ADR com 836034108 2689 144100 SH Sole 144100 Spongetech Delivery Systems, I com 849109103 0 890000 SH Sole 890000 Spreadtrum Communications com 849415203 10909 588100 SH Sole 429400 158700 Srs Labs, Inc. com 78464M106 920 107700 SH Sole 107700 Summer Infant, Inc. com 865646103 1356 169500 SH Sole 169500 Sun Hydraulics com 866942105 1116 25900 SH Sole 19100 6800 Syswin, Inc. com 872058102 2318 369700 SH Sole 369700 TII Network Technologies, Inc. com 872479209 789 273000 SH Sole 273000 Tal Education Group ADR com 874080104 1970 180200 SH Sole 180200 Taleo Corp. com 87424N104 1708 47900 SH Sole 35600 12300 Tesco Corp. com 88157K101 871 39700 SH Sole 29200 10500 The Travelers Co., Inc. com 89417E109 234 3942 SH Sole 3942 Toyota Motor Corp ADR com 892331307 216 2686 SH Sole 2686 Tri-Tech Holding, Inc. com G9103F106 1483 127300 SH Sole 127300 Twin Disc, Inc. com 901476101 6121 189960 SH Sole 157300 32660 Unify Corp. com 904743200 636 231200 SH Sole 231200 United Financial Bancorp, Inc. com 91030T109 1245 75400 SH Sole 75400 Vanda Pharmaceuticals, Inc. com 921659108 782 107300 SH Sole 107300 Vera Bradley, Inc. com 92335C106 5362 127040 SH Sole 75900 51140 Viasat Inc. com 92552V100 785 19700 SH Sole 13900 5800 Vicor Corp. com 925815102 726 44000 SH Sole 32600 11400 Viropharma Inc. com 928241108 2823 141850 SH Sole 100600 41250 Virtusa Corp. com 92827P102 1751 93500 SH Sole 93500 Wal Mart Stores Inc. com 931142103 224 4309 SH Sole 4309 Walgreen Company com 931422109 349 8700 SH Sole 8700 Wave Systems Corp. com 943526301 2188 699200 SH Sole 699200 Wayside Technology Group, Inc. com 946760105 763 55600 SH Sole 55600 Web.com Group, Inc. com 94733A104 8313 570380 SH Sole 452500 117880 Xata Corp. com 983882309 227 95200 SH Sole 95200 Yongye Int'l, Inc. com 98607B106 1190 194100 SH Sole 194100 Yuhe International, Inc. com 988432100 1142 171400 SH Sole 171400 Zix Corp. com 98974P100 2967 802000 SH Sole 767000 35000 Zoo Entertainment, Inc. com 98978F207 329 81600 SH Sole 81600 eMagin Corporation com 29076N206 1699 237600 SH Sole 237600 iSoftStone Holdings Ltd. com 46489B108 1037 56000 SH Sole 56000