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UNITED STATES
SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549
Form 13F
Form 13F COVER PAGE
Report for the Calendar Year or Quarter Ended: December 31, 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.
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 North Aurora, IL February 1,2000
------------------------ ----------------------------- ---------------
[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).)
List of Other Managers Reporting for this Manager:
[If there are no entries in this list, omit this section.]
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Oberweis Asset Management, Inc.
FORM 13F
December 31, 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 415 31000 SH SOLE 30000 1000
ACT Manufacturing Inc. com 000973107 671 17900 SH SOLE 15000 2900
AVT Corporation com 002420107 470 10000 SH SOLE 10000
Advance Paradigm Inc. com 007491103 5542 257000 SH SOLE 230000 27000
Advanced Communication com 00750X109 895 46800 SH SOLE 40000 6800
Advanced Digital com 007525108 486 10000 SH SOLE 10000
Akorn, Inc. com 009728106 244 50000 SH SOLE 50000
American Eagle Outfitters com 02553E106 3402 75600 SH SOLE 66000 9600
Andrx Corporation com 034551101 4185 98900 SH SOLE 82500 16400
Aremissoft Corporation com 040026106 1401 43100 SH SOLE 10000 33100
Audiovox Corporation Class A com 050757103 2904 96000 SH SOLE 68000 28000
Barrett Resources Corporation com 068480201 259 8800 SH SOLE 7000 1800
Biovail Corp. Intl. com 09067K106 281 3000 SH SOLE 3000
Broadvision Inc. com 111412102 306 1800 SH SOLE 1800
Business Resource Group com 12329k104 106 20000 SH SOLE 20000
C-COR.Net Corporation com 125010108 2452 32000 SH SOLE 32000
CAM Data Systems Inc. com 131730103 2426 135702 SH SOLE 100000 35702
CGI Group Incorporated Class A com 39945C109 1391 32500 SH SOLE 32500
Candela Corporation com 136907102 3686 197910 SH SOLE 165000 32910
Carrier Access Corporation com 144460102 1982 29450 SH SOLE 18000 11450
Check Point Software com M22465104 914 4600 SH SOLE 3000 1600
Chevron Corp. com 166751107 390 4500 SH SOLE 4500
Chico's Fas Inc. com 168615102 3102 82450 SH SOLE 66000 16450
Children's Place com 168905107 850 51700 SH SOLE 46000 5700
Citrix Systems Inc. com 177376100 553 4500 SH SOLE 2000 2500
Cognizant Technology Solutions com 192446102 3214 29400 SH SOLE 25000 4400
Compuware Corporation com 205638109 261 7000 SH SOLE 4000 3000
Core, Inc. com 21867p102 191 20000 SH SOLE 20000
Corsair Communications com 220406102 162 20000 SH SOLE 20000
Creative Master Intl., Inc. com 22528Y201 156 61000 SH SOLE 56000 5000
Cree Research, Inc. com 225447101 341 4000 SH SOLE 4000
Crown Group, Inc. com 228359105 99 20000 SH SOLE 20000
Cutter & Buck Inc. com 232217109 1280 84600 SH SOLE 67500 17100
Cybex Computer Products com 232522102 1215 30000 SH SOLE 30000
Cytyc com 232946103 434 7100 SH SOLE 3000 4100
Diamond Tech Partners, Inc. com 252762109 1160 13500 SH SOLE 13500
Digital Biometrics Inc. com 253833107 307 91000 SH SOLE 50000 41000
Digital Lightwave Inc. com 253855100 3667 57300 SH SOLE 48000 9300
E-Tek Dynamics, Inc. com 269240107 337 2500 SH SOLE 2500
ECCS Inc. com 26825H100 3221 255100 SH SOLE 200000 55100
ESS Technology, Inc. com 269151106 1642 74000 SH SOLE 70000 4000
Exactech, Inc. com 30064E109 118 10000 SH SOLE 10000
Excel Technology Inc. com 30067T103 1139 63500 SH SOLE 62500 1000
Fotoball USA, Inc. com 350384103 126 20000 SH SOLE 20000
Frenchtex com 357814102 23 25000 SH SOLE 25000
Genesis Microchip Inc. com 371933102 1960 92800 SH SOLE 50000 42800
Gentner Communications com 37245J105 2436 174000 SH SOLE 100000 74000
Gilat Communications, Ltd. com M50876107 2336 97100 SH SOLE 70000 27100
Hain Food Group Inc com 405219106 1062 47460 SH SOLE 30000 17460
Hieco Corp. com 422806109 218 10000 SH SOLE 10000
ICT Group com 44929Y101 512 41800 SH SOLE 20000 21800
Ikos Systems Inc. com 451716203 906 93500 SH SOLE 70000 23500
Inamed Corp. com 453235103 307 7000 SH SOLE 7000
Infocure Corporation com 45665A108 1998 64050 SH SOLE 45000 19050
Insight Enterprises Inc. com 457650103 325 8000 SH SOLE 7500 500
Intel Corporation com 458140100 279 3390 SH SOLE 3390
Interpore Intl. com 46062W107 157 20000 SH SOLE 20000
Intranet Solutions, Inc. com 460939309 4281 115700 SH SOLE 100000 15700
Intuit Inc. com 461202103 351 5850 SH SOLE 4500 1350
Jakks Pacific Inc. com 47012E106 973 52050 SH SOLE 37500 14550
Javelin Systems, Inc. com 471896100 2642 287600 SH SOLE 260000 27600
King Pharmaceuticals Inc. com 495582108 8984 160250 SH SOLE 133500 26750
Koala Corporation com 499866101 149 10660 SH SOLE 6000 4660
Legato Systems, Inc. com 524651106 344 5000 SH SOLE 5000
Lightbridge Inc. com 532226107 1199 43200 SH SOLE 40000 3200
Loronix Information Systems com 544183106 415 21000 SH SOLE 6000 15000
Magic Software Enterprises Ltd com 559166103 3181 51300 SH SOLE 40000 11300
Manatron Inc. com 562048108 233 36500 SH SOLE 20000 16500
Meade Instruments Corporation com 583062104 285 10000 SH SOLE 10000
Measurement Specialties Inc. com 583421102 495 23700 SH SOLE 10000 13700
Mercury Computer Sys + com 589378108 4893 139800 SH SOLE 112000 27800
Mercury Interactive Corporatio com 589405109 1687 15630 SH SOLE 4000 11630
Meridian Resource Corp. com 58977q109 122 40000 SH SOLE 40000
Micromuse Incorporated com 595094103 340 2000 SH SOLE 2000
Microsoft Corp. com 594918104 350 3000 SH SOLE 3000
Monterey Pasta Co. com 612570101 459 116500 SH SOLE 77000 39500
Motorola Inc. com 620076109 294 2000 SH SOLE 2000
Netsmart Technologies com 64114W306 899 141050 SH SOLE 60000 81050
New Horizons Worldwide com 645526104 148 12500 SH SOLE 12500
Nice Systems Ltd. com 653656108 492 10000 SH SOLE 10000
Noven Pharmaceuticls, Inc. com 670009109 1765 97400 SH SOLE 70000 27400
P.F. Changs China Bistro com 69333y108 378 15200 SH SOLE 10000 5200
Papa John's International Inc. com 698813102 782 30000 SH SOLE 30000
Peregrine Systems com 71366Q101 1991 23650 SH SOLE 20000 3650
Performance Technologies com 71376K102 1447 83280 SH SOLE 65000 18280
Photon Dynamics Inc. com 719364101 1023 26400 SH SOLE 12000 14400
Polycom Inc. com 73172K104 414 6500 SH SOLE 6000 500
Polymedica Corp. com 731738100 3441 148800 SH SOLE 120000 28800
PowerWave Technology com 739363109 604 10350 SH SOLE 6000 4350
Premier Research Worldwide Ltd com 740568100 1171 119300 SH SOLE 85000 34300
Prinktrak International Inc. com 742574106 97 10000 SH SOLE 10000
Qiagen N.A. com 730000106 1510 20000 SH SOLE 20000
Qlogic Corp com 747277101 8785 54950 SH SOLE 44000 10950
Quest Education Corp. com 74835f102 87 10000 SH SOLE 10000
RF Micro Devices, Inc. com 749941100 7460 109000 SH SOLE 86000 23000
RMH Teleservices, Inc. com 749938106 126 20000 SH SOLE 20000
Radiant Systems com 75025N102 2893 72000 SH SOLE 60000 12000
Radisys Corp. com 750459109 306 6000 SH SOLE 6000
Railamerica Inc. com 750753105 171 20000 SH SOLE 20000
Rehabilicare Incorporated com 758944102 80 20000 SH SOLE 20000
Salton Inc. com 795757103 5942 177700 SH SOLE 150000 27700
ScanSource, Inc. com 806037107 1984 48900 SH SOLE 40000 8900
Siebel Systems Inc. com 826170102 655 7800 SH SOLE 3000 4800
Siliconix, Inc. com 827079203 519 3950 SH SOLE 3000 950
Softworks, Inc. com 83404P102 679 75000 SH SOLE 75000
Source Information Management com 836151209 1457 87000 SH SOLE 65000 22000
Spectralink Corp. com 847580107 217 30000 SH SOLE 30000
Stericycle, Inc. com 858912108 941 50000 SH SOLE 50000
Steven Madden Ltd. com 556269108 965 50600 SH SOLE 35000 15600
Strategic Diagnostics, Inc. com 862700101 98 15000 SH SOLE 15000
Suprema Specialties, Inc. com 86859f107 1691 214700 SH SOLE 140000 74700
Surmodics, Inc. com 868873100 300 10000 SH SOLE 10000
TTI Team Telecom com m88258104 544 30000 SH SOLE 30000
Take-Two Interactive Software com 874054109 528 40840 SH SOLE 40000 840
Talx Corporation com 874915105 523 39500 SH SOLE 30000 9500
Titan Corporation com 888266103 471 10000 SH SOLE 10000
Transwitch Corporation com 894065101 4350 59950 SH SOLE 49000 10950
Triton Energy 'A' com G90751101 464 22500 SH SOLE 10000 12500
US Lec Corp. com 90331S109 1517 47030 SH SOLE 40000 7030
US-China Industrial com 90329w302 199 10900 SH SOLE 9000 1900
Ventana Medical Systems com 92276H106 634 25500 SH SOLE 25000 500
Veramark Technologies com 923351100 184 15000 SH SOLE 10000 5000
Verity Inc. com 92343C106 5679 133425 SH SOLE 100000 33425
Visual Networks, Inc. com 928444108 2821 35600 SH SOLE 26000 9600
Vitesse Semiconductor Co. com 928497106 367 7000 SH SOLE 2000 5000
Xeta Corporation com 983909102 498 15000 SH SOLE 15000
Zebra Technologies Corp.-Cl A com 989207105 246 4200 SH SOLE 4200
Zoll Medical Corporation com 989922109 2021 52910 SH SOLE 40000 12910
REPORT SUMMARY 128 DATA RECORDS 175147 0 OTHER MANAGERS ON WHOSE BEHALF REPORT IS FILED
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Form 13F SUMMARY PAGE
Report Summary:
Number of Other Included Managers:
-------------------
Form 13F Information Table Entry Total: 128 Data Records
Form 13F Information Table Value Total: $175,147 (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 manager filing this report.
[If there are no entries in this list, state "NONE" and omit the column
headings and list entries.]
NONE.
