<PAGE>
UNITED STATES
SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549
Form 13F
Form 13F COVER PAGE
Report for the Calendar Year or Quarter Ended: September 30, 1999
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: 951 Ice Cream Dr., Suite 200
North Aurora, IL 60542
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.
Name: Patrick B. Joyce
Title: Executive Vice President
Phone: (800) 323-6166
Signature, Place, and Date of Signing:
/s/ Pat Joyce North Aurora, IL December 28, 1999
- -----------------------
[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 manger are reported in this report and a portion are reported by
other reporting manager(s).)
List of Other Managers reporting for this Manager:
[If there are no entries in this list, omit this section.]
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<TABLE>
OBERWEIS ASSET MANAGEMENT, INC.
FORM 13F
SEPTEMBER 30, 1999
VOTING AUTHORITY
VALUE SHARES/ SH/ PUT/ INVSTMT OTHER -----------------------
NAME OF ISSUER TITLE OF CLASS CUSIP (x$1000) PRN AMT PRN CALL DSCRETN MANAGERS SOLE SHARED NONE
- ------------------------------ ---------------- --------- -------- -------- --- ---- ------- ------------ -------- -------- -------
<S> <C> <C> <C> <C> <C> <C> <C> <C> <C> <C> <C>
4Front Technologies, Inc. com 351042106 275 20000 SH SOLE 20000
AVT Corporation com 002420107 229 7000 SH SOLE 7000
Abacus Direct Corp. com 002553105 2177 18500 SH SOLE 18500
Abercrombie & Fitch Co. com 002896207 314 9400 SH SOLE 7000 2400
Action Performance com 004933107 447 20000 SH SOLE 20000
Advance Paradigm Inc. com 007491103 6971 128500 SH SOLE 115000 13500
Advanced Communication com 00750X109 579 46800 SH SOLE 40000 6800
Advanced Digital com 007525108 275 10000 SH SOLE 10000
Akorn, Inc. com 009728106 216 50000 SH SOLE 50000
American Eagle Outfitters com 02553E106 3823 76850 SH SOLE 66000 10850
American Healthcorp, Inc. com 02649v104 93 15000 SH SOLE 15000
Analytical Surveys Inc. com 032683302 312 20000 SH SOLE 20000
Andrx Corporation com 034551101 5600 108600 SH SOLE 84500 24100
Aremissoft Corporation com 040026106 866 72900 SH SOLE 20000 52900
Audiovox Corporation Class A com 050757103 1521 81100 SH SOLE 60000 21100
Barrett Resources Corporation com 068480201 310 8500 SH SOLE 7000 1500
Biogen Inc. com 090597105 691 8300 SH SOLE 3000 5300
Broadcom Corporation com 111320107 259 2300 SH SOLE 2300
Broadvision Inc. com 111412102 4483 32250 SH SOLE 30000 2250
Business Resource Group com 12329k104 67 20000 SH SOLE 20000
C-COR.Net Corporation com 125010108 847 30000 SH SOLE 30000
CAM Data Systems Inc. com 131730103 1088 104272 SH SOLE 76100 28172
CGI Group Incorporated Class A com 39945C109 656 32500 SH SOLE 32500
Candela Corporation com 136907102 1981 196910 SH SOLE 165000 31910
Carrier Access Corporation com 144460102 1285 29950 SH SOLE 18000 11950
Chattem Inc. com 162456107 562 26000 SH SOLE 25400 600
Check Point Software com M22465104 417 4950 SH SOLE 3000 1950
Chevron Corp. com 166751107 397 4500 SH SOLE 4500
Chico's Fas Inc. com 168615102 2301 81450 SH SOLE 66000 15450
Children's Place com 168905107 1504 57700 SH SOLE 49000 8700
Chirex Inc. com 170038103 1001 38300 SH SOLE 30000 8300
Citrix Systems Inc. com 177376100 469 7900 SH SOLE 4000 3900
Cognizant Technology Solutions com 192446102 1066 34700 SH SOLE 30000 4700
Colorado Medtech, Inc. com 19652U104 1226 87200 SH SOLE 60000 27200
Concord EFS, Inc. com 206197105 204 10000 SH SOLE 10000
Core, Inc. com 21867p102 137 17400 SH SOLE 17400
Creative Master Intl., Inc. com 22528Y201 280 65000 SH SOLE 60000 5000
Cutter & Buck Inc. com 232217109 1428 84600 SH SOLE 67500 17100
Cybex Computer Products com 232522102 1035 30000 SH SOLE 30000
Dental/Medical Diagnostic Syst com 24873K208 79 20000 SH SOLE 20000
Digital Biometrics Inc. com 253833107 168 61000 SH SOLE 38000 23000
ESS Technology, Inc. com 269151106 547 40000 SH SOLE 40000
Elan Corporation PLC com 284131208 267 8000 SH SOLE 8000
Fotoball USA, Inc. com 350384103 122 20000 SH SOLE 20000
Frenchtex com 357814102 6 25000 SH SOLE 25000
Genesis Microchip Inc. com 371933102 1705 92800 SH SOLE 50000 42800
Gentner Communications com 37245J105 1517 178500 SH SOLE 100000 78500
Gilat Communications, Ltd. com M50876107 1384 97100 SH SOLE 70000 27100
Gildan Activewear Inc. com 375916103 533 31700 SH SOLE 20000 11700
Gliatech, Inc. com 37929C103 462 26500 SH SOLE 25000 1500
Hain Food Group Inc com 405219106 1153 46600 SH SOLE 30000 16600
ICT Group com 44929Y101 288 40800 SH SOLE 20000 20800
Impath, Inc. com 45255G101 1608 53700 SH SOLE 50000 3700
Infocure Corporation com 45665A108 1152 64200 SH SOLE 45000 19200
Innovative Medical Services com 45766r109 78 50000 SH SOLE 50000
Intel Corporation com 458140100 247 3290 SH SOLE 3290
Intranet Solutions, Inc. com 460939309 1246 137500 SH SOLE 110000 27500
JDS Uniphase Corporation com 909149106 230 2000 SH SOLE 2000
Jakks Pacific Inc. com 47012E106 1540 39500 SH SOLE 25000 14500
Javelin Systems, Inc. com 471896100 2844 293600 SH SOLE 260000 33600
K-Swiss, Inc. com 482686102 600 19480 SH SOLE 10000 9480
King Pharmaceuticals Inc. com 495582108 3948 111400 SH SOLE 89000 22400
Legato Systems, Inc. com 524651106 205 5000 SH SOLE 5000
Loronix Information Systems com 544183106 312 24000 SH SOLE 6000 18000
Magic Software Enterprises Ltd com 559166103 394 19700 SH SOLE 10000 9700
Manatron Inc. com 562048108 194 36500 SH SOLE 20000 16500
Meade Instruments Corporation com 583062104 232 10000 SH SOLE 10000
Measurement Specialties Inc. com 583421102 400 20700 SH SOLE 10000 10700
Mercury Interactive Corporatio com 589405109 1271 19380 SH SOLE 5000 14380
Micromuse Incorporated com 595094103 1586 24500 SH SOLE 24000 500
Microsoft Corp. com 594918104 297 3300 SH SOLE 3300
Mindspring Enterprises com 602683104 4050 150700 SH SOLE 126000 24700
Mobil Corp. com 607059102 612 6200 SH SOLE 6200
Navigant Consulting Company com 63935n107 875 20000 SH SOLE 20000
Netsmart Technologies com 64114W306 604 87800 SH SOLE 30000 57800
Network Appliance Inc. com 64120L104 2114 30000 SH SOLE 30000
New Horizons Worldwide com 645526104 214 13500 SH SOLE 12500 1000
Open Text Corporation com 683715106 780 39000 SH SOLE 39000
Optical Coating Laboratory com 683829105 230 2500 SH SOLE 2500
P.F. Changs China Bistro com 69333y108 312 15400 SH SOLE 10000 5400
Papa John's International Inc. com 698813102 1787 45000 SH SOLE 45000
Peregrine Systems com 71366Q101 1273 30600 SH SOLE 26000 4600
Performance Technologies com 71376K102 1905 87580 SH SOLE 65000 22580
Pervasive Software com 715710109 238 6900 SH SOLE 5200 1700
Polycom Inc. com 73172K104 297 6500 SH SOLE 6000 500
Polymedica Corp. com 731738100 2446 121550 SH SOLE 90000 31550
Power Wave Technology com 739363109 287 6000 SH SOLE 6000
Pre-Paid Legal Services com 740065107 236 6200 SH SOLE 6200
Qiagen N.A. com 730000106 2677 59500 SH SOLE 59500
Qlogic Corp com 747277101 4443 62060 SH SOLE 44000 18060
Quest Education Corporation com 74835f102 76 10000 SH SOLE 10000
Questron Technology, Inc. com 748372208 69 20000 SH SOLE 20000
RCM Technologies com 749360400 241 23000 SH SOLE 20000 3000
RF Micro Devices, Inc. com 749941100 5319 112800 SH SOLE 86000 26800
RMH Teleservices, Inc. com 749938106 75 20000 SH SOLE 20000
Radiant Systems com 75025N102 422 24200 SH SOLE 20000 4200
Railamerica Inc. com 750753105 196 20000 SH SOLE 20000
Rehabilicare Incorporated com 758944102 77 20000 SH SOLE 20000
Salton Inc. com 795757103 5361 177600 SH SOLE 150000 27600
Sapient Corporation com 803062108 1102 12000 SH SOLE 12000
ScanSource, Inc. com 806037107 282 10000 SH SOLE 10000
Seracare Inc. com 817473101 40 10000 SH SOLE 10000
Siebel Systems Inc. com 826170102 614 9200 SH SOLE 5000 4200
Softworks, Inc. com 83404P102 415 80000 SH SOLE 80000
Spectralink Corp. com 847580107 434 90100 SH SOLE 30000 60100
Stericycle, Inc. com 858912108 747 50000 SH SOLE 50000
Steven Madden Ltd. com 556269108 668 52900 SH SOLE 35000 17900
Sunrise Assisted Living com 86768K106 535 21000 SH SOLE 20200 800
Suprema Specialties, Inc. com 86859f107 1726 215700 SH SOLE 140000 75700
TTI Team Telecom com m88258104 124 12200 SH SOLE 12200
Take-Two Interactive Software com 874054109 422 40000 SH SOLE 40000
Talx Corporation com 874915105 193 24500 SH SOLE 15000 9500
The Laser Center com 872934104 364 15000 SH SOLE 15000
Transwitch Corporation com 894065101 3416 60200 SH SOLE 49000 11200
Tricom, S.A. com 89612a100 325 40000 SH SOLE 40000
US Lec Corp. com 90331S109 1242 46200 SH SOLE 40000 6200
Veramark Technologies com 923351100 112 10000 SH SOLE 10000
Veritas Software Corp. com 923436109 1038 14000 SH SOLE 14000
Verity Inc. com 92343C106 5303 75490 SH SOLE 48200 27290
Visual Networks, Inc. com 928444108 1418 36300 SH SOLE 26000 10300
Visx Inc. Del com 92844S105 219 3000 SH SOLE 3000
Vitesse Semiconductor Co. com 928497106 539 6500 SH SOLE 4000 2500
Xeikon NV ADR com 984003103 860 41200 SH SOLE 40000 1200
Zoll Medical Corporation com 989922109 2165 73710 SH SOLE 60000 13710
REPORT SUMMERY 124 DATA RECORDS 135535 0 OTHER MANAGERS ONWHOSE BEHALF REPORT IS FILED
</TABLE>
<PAGE>
FORM 13F SUMMARY PAGE
Report Summary:
Number of other Included Managers: ___________________
Form 13F Information Table Entry Total: 124 Data Records
Form 13F Information Table Value Total: $ 135,535 (thousandths)
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.
