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OMB APPROVAL
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OMB Number: 3235-0006
Expires: FEBRUARY 28, 1994
Estimated average burden
hours per response....24.60
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UNITED STATES
SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549
INFORMATION REQUIRED OF INSTITUTIONAL INVESTMENT MANAGERS PURSUANT
TO SECTION 13(f) OF THE SECURITIES EXCHANGE ACT OF 1934 AND RULES THEREUNDER
Report for the Calendar Year or Quarter Ended June 30, 1999.
------- --
- --------------------------------------------------------------------------------
(Please read instructions before preparing form.)
- --------------------------------------------------------------------------------
If amended report check here: [_]
- --------------------------------------------------------------------------------
Name of Institutional Investment Manager
125 HIGH STREET, 29TH FLOOR BOSTON, MA 02110
- --------------------------------------------------------------------------------
Business Address (Street) (City) (STATE) (Zip)
C. H. RITT III VICE PRESIDENT 617-342-3200
- --------------------------------------------------------------------------------
Name, Phone No., and Title of Person Duly Authorized to submit this Report.
- ---------------------------------ATTENTION--------------------------------------
International missstatement or omissions of facts constitute Federal Criminal
Violations.
See 18 U.S.C. 101 and 15 U.S.C. 78ff(a).
- --------------------------------------------------------------------------------
The institutional investment manager submitting this form and its
attachments and the person by whom it is signed represent hereby that all
information contained therein is true, correct and complete. It is understood
that all required items, statements and schedules are considered integral parts
of this Form and that the submission of any amendment represents that all
unamended items, statements and schedules remain true, correct and complete as
previously submitted.
Pursuant to the requirements of Securities Exchange Act of 1934, the
undersigned institutional investment manager has caused this report to be signed
on its behalf in the city of BOSTON and State of MA on the 4 day of AUGUST,
------ -- - ------
1999.
--
ESSEX INVESTMENT MANAGEMENT COMPANY, LLC
-------------------------------------------------
(Name of Institutional Investment Manager)
/s/ Charles H. Ritt III
-------------------------------------------------
(Manual Signature of Person Duly Authorized
to Submit This Report)
Name and 13F file numbers of ALL Institutional Investment Managers with respect
to which this schedule is filled (other than the one filing this report): (List
in alphabetical order).
13F File Number will be assigned to Institutional Investment Managers after they
file their first report.
<TABLE>
Name: 13F File No: Name: 13F File No.:
<S> <C> <C> <C>
- ----------------------------------- ------------ ------------------------- --------------
1. AFFILIATED MANAGERS GROUP, INC. PENDING 6.
- ----------------------------------- ------------ ------------------------- --------------
2. 7.
- ----------------------------------- ------------ ------------------------- --------------
3. 8.
- ----------------------------------- ------------ ------------------------- --------------
4. 9.
- ----------------------------------- ------------ ------------------------- --------------
5. 10.
- ----------------------------------- ------------ ------------------------- --------------
SEC 1685 (5/91)
</TABLE>
<PAGE>
<TABLE>
<CAPTION>
FORM 13F 6/30/99
REPORTING MANAGER: ESSEX INVESTMENT MGMT CO PAGE 1
- ------------------------------------------------------------------------------------------------------------------------------------
ITEM 1 ITEM 2 ITEM 3 ITEM 4 ITEM 5 ITEM 6 ITEM 7 ITEM 8
NAME OF ISSUER TITLE CUSIP FAIR SHARES OR INVESTMENT DISCRETION MANA- VOTING AUTHORITY
OF NUMBER MARKET PRINCIPAL SHARED GERS
CLASS VALUE AMOUNT SHARED- SHARED OTHER SOLE SHARED NONE
DEFINED (B) (C) (A) (B) (C)
- ------------------------------------------------------------------------------------------------------------------------------------
<S> <C> <C> <C> <C> <C> <C> <C> <C> <C> <C> <C>
AGCO CORP COMMON 001084102 113125 10000 10000 10000
AT&T CORP COMMON 001957109 938041 16807 16807 12100 4707
AT&T CORP COMMON 001957208 3434655 93460 93460 89660 3800
AAVID THERMAL TECHNOLOGI COMMON 002539104 1591556 70345 70345 32970 37375
ABACUS DIRECT CORP COMMON 002553105 773175 8450 8450 6750 1700
ABBOTT LABS COMMON 002824100 3249531 71615 71615 29715 41900
ABERCROMBIE & FITCH CO COMMON 002896207 12322080 256710 256710 199470 57240
ABOVENET COMMUNICATIONS COMMON 003743101 496613 12300 12300 12300
ACCREDO HEALTH INC COMMON 00437V104 9363880 285920 285920 222320 63600
ADELPHIA COMMUNICATIONS COMMON 006848105 13847981 217650 217650 178575 39075
ADVANCED PARADIGM INC COMMON 007491103 47792890 783490 783490 665240 118250
ADVANCED MARKETING SVCS COMMON 00753T105 173250 11550 11550 11550
ADVANTAGE LEARNING SYSTE COMMON 00757K100 31459560 1421901 1421901 1169401 252500
AETNA INC COMMON 008117103 317414 3549 3549 3549
AIR EXPRESS INTL CORP COMMON 009104100 11147999 439330 439330 376130 63200
AIR PRODS & CHEMS INC COMMON 009158106 221375 5500 5500 5500
AIRTOUCH COMMUNICATIONS COMMON 00949T100 269679 2505 2505 2505
ALBANY MOLECULAR RESH IN COMMON 012423109 5028791 169035 169035 157960 11075
ALCOA INC COMMON 013817101 235125 3800 3800 3800
--------- ------- ------- ------ ------ -------- ------ ------
COLUMN TOTALS 142776718 3883917 3883917 3175946 707971
</TABLE>
<PAGE>
<TABLE>
<CAPTION>
FORM 13F 6/30/99
REPORTING MANAGER: ESSEX INVESTMENT MGMT CO PAGE 2
- ------------------------------------------------------------------------------------------------------------------------------------
ITEM 1 ITEM 2 ITEM 3 ITEM 4 ITEM 5 ITEM 6 ITEM 7 ITEM 8
NAME OF ISSUER TITLE CUSIP FAIR SHARES OR INVESTMENT DISCRETION MANA- VOTING AUTHORITY
OF NUMBER MARKET PRINCIPAL SHARED GERS
CLASS VALUE AMOUNT SHARED- SHARED OTHER SOLE SHARED NONE
DEFINED (B) (C) (A) (B) (C)
- ------------------------------------------------------------------------------------------------------------------------------------
<S> <C> <C> <C> <C> <C> <C> <C> <C> <C> <C> <C>
ALLAIRE CORP COMMON 016714107 28951991 424205 424205 338340 85865
ALLEGIANCE TELECOM INC COMMON 01747T102 37093854 675970 675970 553195 122775
ALLIANCE SEMICONDUCTOR C COMMON 01877H100 1493109 150250 150250 70800 79450
ALLIEDSIGNAL INC COMMON 019512102 504000 8000 8000 8000
ALLTEL CORP COMMON 020039103 1737665 24303 24303 14380 9923
ALPHA 1 BIOMEDICALS INC COMMON 020910105 5600 112000 112000 112000
AMAZON COM INC COMMON 023135106 90126036 720288 720288 543128 177160
AMERICA ONLINE INC DEL COMMON 02364J104 95547320 868612 868612 721470 147142
AMERICAN BIOGENETIC SCIE COMMON 024611105 10000 10000 10000 10000
AMERICAN EXPRESS CO COMMON 025816109 4913130 37757 37757 27580 10177
AMERICAN GENERAL CORP COMMON 026351106 865908 11488 11488 11488
AMERICAN HOME PRODS CORP COMMON 026609107 2794449 48705 48705 3900 44805
AMERICAN INTL GROUP INC COMMON 026874107 62088331 529538 529538 453162 76376
AMERICAN TOWER CORP COMMON 029912201 324240 13510 13510 13510
ANADARKO PETE CORP COMMON 032511107 77128630 2095175 2095175 1806035 289140
ANHEUSER BUSCH COS INC COMMON 035229103 15399467 217085 217085 157290 59795
AON CORP COMMON 037389103 928125 22500 22500 22500
APACHE CORP COMMON 037411105 12517479 320961 320961 278361 42600
APPLE COMPUTER INC COMMON 037833100 213038 4600 4600 4600
--------- -------- ------- ------ ------ ------- ------ -------
COLUMN TOTALS 432642372 6294947 4980241 1314706
</TABLE>
<PAGE>
<TABLE>
<CAPTION>
FORM 13F 6/30/99
REPORTING MANAGER: ESSEX INVESTMENT MGMT CO PAGE 3
- ------------------------------------------------------------------------------------------------------------------------------------
ITEM 1 ITEM 2 ITEM 3 ITEM 4 ITEM 5 ITEM 6 ITEM 7 ITEM 8
NAME OF ISSUER TITLE CUSIP FAIR SHARES OR INVESTMENT DISCRETION MANA- VOTING AUTHORITY
OF NUMBER MARKET PRINCIPAL SHARED GERS
CLASS VALUE AMOUNT SHARED- SHARED OTHER SOLE SHARED NONE
DEFINED (B) (C) (A) (B) (C)
- ------------------------------------------------------------------------------------------------------------------------------------
<S> <C> <C> <C> <C> <C> <C> <C> <C> <C> <C> <C>
APPLIED MATLS INC COMMON 038222105 2299359 31125 31125 27725 3400
APPLIED MICRO CIRCUITS CO COMMON 03822W109 16269050 197800 197800 157600 40200
ARIBA INC COMMON 04033V104 33266794 342075 342075 246865 95210
ARMOR HOLDINGS INC COMMON 042260109 1158563 111000 111000 111000
ARTISAN COMPONENTS INC COMMON 042923102 1242713 106900 106900 50400 56500
ASARCO INC COMMON 043413103 410113 21800 21800 21800
ASK JEEVES INC COMMON 045174109 434000 31000 31000 18645 12355
ASPECT DEV INC COMMON 045234101 7612750 411500 411500 384930 26570
AT HOME CORP COMMON 045919107 7102112 131673 131673 97290 34383
ATLANTIC RICHFIELD CO COMMON 048825103 451238 5400 5400 5400
AUTOMATIC DATA PROCESSING COMMON 053015103 212080 4820 4820 4820
AVANT IMMUNOTHERAPEUTICS COMMON 053491106 63750 30000 30000 30000
AVERY DENNISON CORP COMMON 053611109 307913 5100 5100 5100
AVID TECHNOLOGY INC COMMON 05367P100 1140038 70700 70700 70700
AXENT TECHNOLOGIES INC COMMON 05459C108 314003 28225 28225 28225
BJ SVCS CO COMMON 055482103 23353799 793335 793335 656385 136950
BP AMOCO P L C COMMON 055622104 2253220 20767 20767 2024 18743
BAKER HUGHES INC COMMON 057224107 9332263 278575 278575 254975 23600
BANK OF AMERICA CORP COMMON 060505104 300581 4100 4100 4100
--------- ------- ------- ------ ------ ------- ------ ------
COLUMN TOTALS 107524336 2625895 2625895 2110839 515056
</TABLE>
<PAGE>
<TABLE>
<CAPTION>
FORM 13F 6/30/99
REPORTING MANAGER: ESSEX INVESTMENT MGMT CO PAGE 4
- ------------------------------------------------------------------------------------------------------------------------------------
ITEM 1 ITEM 2 ITEM 3 ITEM 4 ITEM 5 ITEM 6 ITEM 7 ITEM 8
NAME OF ISSUER TITLE CUSIP FAIR SHARES OR INVESTMENT DISCRETION MANA- VOTING AUTHORITY
OF NUMBER MARKET PRINCIPAL SHARED GERS
CLASS VALUE AMOUNT SHARED- SHARED OTHER SOLE SHARED NONE
DEFINED (B) (C) (A) (B) (C)
- ------------------------------------------------------------------------------------------------------------------------------------
<S> <C> <C> <C> <C> <C> <C> <C> <C> <C> <C> <C>
BANK NEW YORK INC COMMON 064057102 227463 6200 6200 1200 5000
BANK ONE CORP COMMON 06423A103 691402 11608 11608 3096 6512
BANKBOSTON CORP COMMON 06605R106 5474465 107080 107080 93080 14000
BAUSCH & LOMB INC COMMON 071707103 8563793 111945 111945 73815 38130
BEA SYS INC COMMON 073325102 2388253 83615 83615 39440 44175
BEAR STEARNS COS INC COMMON 073902108 310841 6649 6649 6649
BED BATH & BEYOND INC COMMON 075896100 3330443 56505 56505 53205 33300
BELL ATLANTIC CORP COMMON 077853109 640021 9790 9790 1200 8590
BELLSOUTH CORP COMMON 079860102 225182 4882 4882 3292 1590
BEST BUY INC COMMON 086516101 1607850 23820 23820 23420 400
BIOGEN INC COMMON 090597105 13486331 209700 209700 185680 24020
BLOCK H & R INC COMMON 083671105 306650 6133 6133 3900 2233
BLUESTONE SOFTWARE INC COMMON 085991105 2075004 762869 762869 431986 330883
BOSTON SCIENTIFIC CORP COMMON 101137107 6259995 142475 142475 123875 18600
BOTTOMLINE TECH DEL INC COMMON 101388106 617980 11660 11660 6200 5460
BRIGHT HORIZON FAMILY SO COMMON 109195107 7003984 371072 371072 249175 121897
BRISTOL MYERS SQUIBB CO COMMON 110122108 567445 8056 8056 3500 4556
BROADCAST COM INC COMMON 111310108 111428943 85570 85570 42645 42925
BROADCOM CORP COMMON 111320107 85985052 594785 594785 479960 114835
--------- ------- ------- ------ ------ ------- ------ ------
COLUMN TOTALS 151191096 2644424 2644424 1818669 825755
</TABLE>
<PAGE>
<TABLE>
<CAPTION>
FORM 13F 6/30/99
REPORTING MANAGER: ESSEX INVESTMENT MGMT CO PAGE 5
- ------------------------------------------------------------------------------------------------------------------------------------
ITEM 1 ITEM 2 ITEM 3 ITEM 4 ITEM 5 ITEM 6 ITEM 7 ITEM 8
NAME OF ISSUER TITLE CUSIP FAIR SHARES OR INVESTMENT DISCRETION MANA- VOTING AUTHORITY
OF NUMBER MARKET PRINCIPAL SHARED GERS
CLASS VALUE AMOUNT SHARED- SHARED OTHER SOLE SHARED NONE
DEFINED (B) (C) (A) (B) (C)
- ------------------------------------------------------------------------------------------------------------------------------------
<S> <C> <C> <C> <C> <C> <C> <C> <C> <C> <C> <C>
BROCADE COMMUNICATIONS S COMMON 111621108 46966991 487020 487020 341570 145450
BUCA INC COMMON 117769109 7577213 459225 459225 397190 62035
BUFFETS INC COMMON 1198B2108 2320700 201800 201800 201800
BURLINGTON RES INC COMMON 122014103 24300661 561865 561865 497000 64865
BURNHAM PACIFIC PPTYS COMMON 12232C108 290883 23625 23625 775 22850
CBT GROUP PUB LTD COMMON 124853300 8803575 533550 533550 449900 83650
CBS CORP COMMON 12490K107 8059063 185000 185000 162500 22500
C-CUBE MICROSYSTEMS COMMON 125015107 2156334 68050 68050 45100 22950
C H ROBINSON WORLDWIDE COMMON 12541W100 12759416 347195 347195 304870 42325
CMGI INC COMMON 125750109 170728066 1496794 1496794 1262205 234589
CNET INC COMMON 125945105 26507500 460000 460000 409300 50700
CSK AUTO CORP COMMON 125965103 10497330 388790 388790 309890 78900
CSG SYS INTL INC COMMON 126349109 2618750 100000 100000 100000
CTC COMMUNICATIONS CORP COMMON 126418102 2683200 137600 137600 97550 40050
CVS CORP COMMON 126650100 41845710 824546 824546 640491 184055
C PORT SERIES C COMMON 126983104 999999 366300 366300 366300
CABOT CORP COMMON 127055101 273923 11325 11325 11325
CALLAWAY GOLF CO COMMON 131193104 731250 50000 50000 50000
CAREER EDUCATION CORP COMMON 141665109 365175 10800 10800 3300 7500
--------- ------- ------- ------ ------ ------- ------ -------
COLUMN TOTALS 370485739 6713845 6713485 5284766 1428719
</TABLE>
<PAGE>
<TABLE>
<CAPTION>
FORM 13F 6/30/99
REPORTING MANAGER: ESSEX INVESTMENT MGMT CO PAGE 6
- ------------------------------------------------------------------------------------------------------------------------------------
ITEM 1 ITEM 2 ITEM 3 ITEM 4 ITEM 5 ITEM 6 ITEM 7 ITEM 8
NAME OF ISSUER TITLE CUSIP FAIR SHARES OR INVESTMENT DISCRETION MANA- VOTING AUTHORITY
OF NUMBER MARKET PRINCIPAL SHARED GERS
CLASS VALUE AMOUNT SHARED- SHARED OTHER SOLE SHARED NONE
DEFINED (B) (C) (A) (B) (C)
- ------------------------------------------------------------------------------------------------------------------------------------
<S> <C> <C> <C> <C> <C> <C> <C> <C> <C> <C> <C>
CELESTIAL SEASONINGS INC COMMON 151016102 13719258 638105 638105 487395 150710
CENDANT CORP COMMON 151313103 6999930 341460 341460 262495 78965
CENTOCOR INC COMMON 152342101 766981 16450 16450 16150 300
CENTRAL PKG CORP COMMON 154785109 205500 6000 6000 6000
CENTURYTEL INC COMMON 156700106 3917601 98556 98556 68322 30324
CHANCELLOR MEDIA CORP COMMON 158915108 4841078 87820 87820 75720 12100
CHASE MANHATTAN CORP NEW COMMON 16161A108 492531 5694 5694 5694
CHECKFREE HLDGS CORP COMMON 162816102 1130752 41025 41025 41025
CHECKPOINT SYSTEMS INC COMMON 162825103 145681 16300 16300 16300
CHEVRON CORPORATION COMMON 166751107 764588 8043 8043 2190 5853
CHUBB CORP COMMON 171232101 417000 6000 6000 6000
CIENA CORP COMMON 171779101 512855 16989 16989 16989
CINAR CORP COMMON 171905201 1148571 50000 50000 50000
CINAR CORP COMMON 171905300 1713775 69950 69950 53550 16400
CIRCUIT CITY STORE-GRP COMMON 172737108 7195875 77375 77375 67250 10125
CISCO SYS INC COMMON 17275R102 72655537 1127535 1127535 959309 168225
CITIGROUP INC COMMON 172967101 848493 17863 17863 9015 8848
CLEAR CHANNEL COMMUNICAT COMMON 184502102 14838452 215245 215245 183450 31795
CLOROX CO DEL COMMON 189054109 581594 5445 5445 3195 2250
--------- ------- ------- ------ ------ ------- ------ ------
COLUMN TOTALS 132896051 2845855 2845855 2266035 579820
</TABLE>
<PAGE>
<TABLE>
<CAPTION>
FORM 13F 6/30/99
REPORTING MANAGER: ESSEX INVESTMENT MGMT CO PAGE 7
- ------------------------------------------------------------------------------------------------------------------------------------
ITEM 1 ITEM 2 ITEM 3 ITEM 4 ITEM 5 ITEM 6 ITEM 7 ITEM 8
NAME OF ISSUER TITLE CUSIP FAIR SHARES OR INVESTMENT DISCRETION MANA- VOTING AUTHORITY
OF NUMBER MARKET PRINCIPAL SHARED GERS
CLASS VALUE AMOUNT SHARED- SHARED OTHER SOLE SHARED NONE
DEFINED (B) (C) (A) (B) (C)
- ------------------------------------------------------------------------------------------------------------------------------------
<S> <C> <C> <C> <C> <C> <C> <C> <C> <C> <C> <C>
COBALT NETWORK, INC. COMMON 190990101 749997 202702 202702 202702
COCA COLA CO COMMON 191216100 1789754 28867 28867 13930 14937
COGNEX CORP COMMON 192422103 4751734 150550 150550 71800 78750
COLGATE PALMOLIVE CO COMMON 194162103 788000 8000 8000 8000
COMCAST CORP - CL A COMMON 200300101 2304713 64355 64355 61005 3350
COMCAST CORP - SP A COMMON 200300200 3434198 89345 89345 81095 8250
COMMSCOPE INC COMMON 203372107 28023859 911345 911345 732390 178955
CONVERSE TECHNOLOGY INC COMMON 205862402 11852745 156990 156990 101865 55125
CONCENTRIC NETWORK CORP COMMON 20589R107 6161250 155000 155000 144200 10800
CONCORD COMMUNICATIONS I COMMON 206186108 1071225 23805 23805 21330 2475
CONCORD EFS INC COMMON 206197105 1057813 25000 25000 19500 5500
CONEXANT SYSTEMS INC COMMON 207142100 465371 8015 8015 3765 4250
CONOCO INC COMMON 208251306 468300 16800 16800 16800
COOPER CAMERON CORP COMMON 216640102 232011 6260 6260 6260
COOPER MTN NETWORKS INC COMMON 217510106 2889847 372943 372943 295325 77618
CORNING INC COMMON 219350105 254904 3635 3635 2800 635
CORPORATE EXECUTIVE BRD COMMON 21956R102 714806 20100 20100 13810 6290
COSTCO COMPANIES INC COMMON 221609102 10382345 129678 129678 79775 49903
COUNTRYWIDE CR INDS INC COMMON 222372104 286425 6700 6700 6700
--------- ------- ------- ------ ------ ------- ------ ------
COLUMN TOTALS 103599299 2380090 2380090 1665650 714440
</TABLE>
<PAGE>
<TABLE>
<CAPTION>
FORM 13F 6/30/99
REPORTING MANAGER: ESSEX INVESTMENT MGMT CO PAGE 8
- ------------------------------------------------------------------------------------------------------------------------------------
ITEM 1 ITEM 2 ITEM 3 ITEM 4 ITEM 5 ITEM 6 ITEM 7 ITEM 8
NAME OF ISSUER TITLE CUSIP FAIR SHARES OR INVESTMENT DISCRETION MANA- VOTING AUTHORITY
OF NUMBER MARKET PRINCIPAL SHARED GERS
CLASS VALUE AMOUNT SHARED- SHARED OTHER SOLE SHARED NONE
DEFINED (B) (C) (A) (B) (C)
- ------------------------------------------------------------------------------------------------------------------------------------
<S> <C> <C> <C> <C> <C> <C> <C> <C> <C> <C> <C>
COVAD COMMUNICATIONS GRO COMMON 222814204 94824066 1778646 1778646 1382391 396255
COX COMMUNICATIONS INC N COMMON 224044107 703855 19120 19120 16120 3000
CRITICAL PATH INC COMMON 22674V100 20422758 369225 369225 266775 102450
CYBEAR INC COMMON 23243P103 687119 49300 49300 49300
CYTYC CORP COMMON 232946103 2050425 105150 105150 91950 13200
DSP COMMUNICATIONS INC COMMON 23332K106 7916948 274180 274180 215150 59030
DAYTON HUDSON CORP COMMON 239753106 221650 3410 3410 3410
DELIA'S INC COMMON 246885107 9283815 687690 687690 518690 169000
DESCARTES SYS GROUP INC COMMON 249906108 149344 29500 29500 29500
DEUTSCHE TELEKOM AG COMMON 251566105 1128075 26700 26700 22700 4000
DEUTSCHE TELEKOM AG COMMON 251566105 726066 17185(W) 17185 17185
DIAMOND OFFSHORE DRILLIN COMMON 25271C102 913249 32185 32185 32185
DIGITAL RIV INC COMMON 253888104 8809588 264950 264950 221420 43530
DIGITAL LAVA INC COMMON 253928105 315625 50000 50000 50000
DIGITAL LAVA INC COMMON 253928105 157813 25000(W) 25000 25000
DOLLAR TREE STORES INC COMMON 256747106 16741428 380487 380487 333137 47350
DONALDSON LUFKIN & JENRE COMMON 257661108 1358638 22550 22550 18950 3600
DOUBLECLICK INC COMMON 258609304 2391372 26064 26064 5300 20764
DRKOOP COM INC COMMON 262098106 792094 49700 49700 43915 5785
--------- ------- ------- ------ ------ ------- ------ ------
COLUMN TOTALS 169593925 4211042 4211042 3343078 867964
</TABLE>
<PAGE>
<TABLE>
<CAPTION>
FORM 13F 6/30/99
REPORTING MANAGER: ESSEX INVESTMENT MGMT CO PAGE 9
- ------------------------------------------------------------------------------------------------------------------------------------
ITEM 1 ITEM 2 ITEM 3 ITEM 4 ITEM 5 ITEM 6 ITEM 7 ITEM 8
NAME OF ISSUER TITLE CUSIP FAIR SHARES OR INVESTMENT DISCRETION MANA- VOTING AUTHORITY
OF NUMBER MARKET PRINCIPAL SHARED GERS
CLASS VALUE AMOUNT SHARED- SHARED OTHER SOLE SHARED NONE
DEFINED (B) (C) (A) (B) (C)
- ------------------------------------------------------------------------------------------------------------------------------------
<S> <C> <C> <C> <C> <C> <C> <C> <C> <C> <C> <C>
DSET CORP COMMON 262504103 882244 63300 63300 42000 21300
DU PONT E I DE NEMOURS & COMMON 263534109 779582 11412 11412 1550 9862
DUKE ENERGY CORP COMMON 264399106 276270 5075 5075 208 4867
DUN & BRADSTREET CORP COMMON 26483B106 384497 10850 10850 10850
DYCOM INDS INC COMMON 267475101 952000 17000 17000 17000
E-LDAN INC COMMON 26861P107 1361256 35300 35300 27500 7800
E M C CORP MASS COMMON 268648102 60567650 1101230 1101230 1008800 92430
ENSCO INTL INC COMMON 26874Q10D 8027834 402650 402650 360950 41700
ESAT TELECOM GROUP PLC COMMON 26883Y102 1501841 34230 34230 23325 10905
E-TEK DYNAMICS INC COMMON 26924O107 2240194 47100 47100 25100 22000
EARTHLINK NETWORK INC COMMON 270322100 4341788 70670 70670 61270 9400
EBAY INC COMMON 278642103 1665125 11000 11000 4100 6900
EMULEX CORP COMMON 292475209 10065248 90525 90525 40900 49625
ENERGIS PLC ADR COMMON 29266H100 10047170 84430 84430 70800 13630
ENRON CORP COMMON 293561106 621300 7600 7600 1200 6400
ENTERCOM COMMUNICATIONS COMMON 293639100 1372275 32100 32100 18300 13800
EQUANT N V COMMON 294409107 94841145 1003610 1003610 779390 224220
EQUITY OFFICE PROPERTIES COMMON 294741103 384375 15000 15000 6200 8800
ERICSSON L M TEL CO COMMON 294821400 1933431 58700 58700 47800 10900
--------- ------- ------- ------ ------ ------- ------ ------
COLUMN TOTALS 202245227 3101782 3101782 2536393 565389
</TABLE>
<PAGE>
<TABLE>
<CAPTION>
FORM 13F 6/30/99
REPORTING MANAGER: ESSEX INVESTMENT MGMT CO PAGE 10
- ------------------------------------------------------------------------------------------------------------------------------------
ITEM 1 ITEM 2 ITEM 3 ITEM 4 ITEM 5 ITEM 6 ITEM 7 ITEM 8
NAME OF ISSUER TITLE CUSIP FAIR SHARES OR INVESTMENT DISCRETION MANA- VOTING AUTHORITY
OF NUMBER MARKET PRINCIPAL SHARED GERS
CLASS VALUE AMOUNT SHARED- SHARED OTHER SOLE SHARED NONE
DEFINED (B) (C) (A) (B) (C)
- ------------------------------------------------------------------------------------------------------------------------------------
<S> <C> <C> <C> <C> <C> <C> <C> <C> <C> <C> <C>
ESSEX ENERGY FUND LP COMMON 296996101 6715995 6500 6500 6500
EVEREST REINS HLDGS INC COMMON 299808105 362138 11100 11100 4500 6600
EXCEL SWITCHING CORP COMMON 30067V108 6195566 206950 206950 180200 26750
EXCHANGE APPLICATIONS COMMON 300867108 497150 12200 12200 8700 3500
EXODUS COMMUNICATIONS IN COMMON 302088109 45566655 379920 379920 317030 62890
EXPEDITORS INTL WASH INC COMMON 302130109 23256513 853450 853450 697950 155500
EXPRESS SCRIPTS INC COMMON 302182100 12108521 201180 201180 169255 31925
EXTREME NETWORKS INC COMMON 30226D106 14289181 246100 246100 177700 68400
EXXON CORP COMMON 302290101 2113919 27409 27409 15534 11875
ESSEX HIGH TECH (USA) LP COMMON 304991102 5762640 1000 1000 1000
FDX CORP COMMON 31304N107 2717925 50100 50100 42300 7800
ESSEX HIGH TECH FUND LP COMMON 313999104 1266986 180 180 180
FINET COM INC COMMON 317922300 6B3214 122825 122825 122825
ESSEX PERFORMANCE FUND COMMON 330995101 1592913 110053 110053 110053
FIRST UN CORP COMMON 337358105 2112614 44830 44830 44830
FIRST YRS INC COMMON 337610109 240000 16000 16000 16000
FIRSTCOM CORP COMMON 33763T104 333788 38700 38700 38700
FLEXPORT MID CAP COMMON 339994105 909870 390000 390000 390000
FLEXPORT LARGE CAP COMMON 339996100 1587950 650000 650000 650000
--------- ------- ------- ------ ------ ------ ------- ------ ------
COLUMN TOTALS 128313537 3368497 3368497 1843024 1525473
</TABLE>
<PAGE>
<TABLE>
<CAPTION>
FORM 13F 6/30/99
REPORTING MANAGER: ESSEX INVESTMENT MGMT CO PAGE 11
- ------------------------------------------------------------------------------------------------------------------------------------
ITEM 1 ITEM 2 ITEM 3 ITEM 4 ITEM 5 ITEM 6 ITEM 7 ITEM 8
NAME OF ISSUER TITLE CUSIP FAIR SHARES OR INVESTMENT DISCRETION MANA- VOTING AUTHORITY
OF NUMBER MARKET PRINCIPAL SHARED GERS
CLASS VALUE AMOUNT SHARED- SHARED OTHER SOLE SHARED NONE
DEFINED (B) (C) (A) (B) (C)
- ------------------------------------------------------------------------------------------------------------------------------------
<S> <C> <C> <C> <C> <C> <C> <C> <C> <C> <C> <C>
FOREST LABS INC COMMON 345838106 18984006 410465 410465 384150 26315
FORTE SOFTWARE INC COMMON 349546101 1917156 197900 197900 93200 104700
FORWARD AIR CORP COMMON 349853101 774000 27520 27520 27520
FOX ENTMT GROUP INC COMMON 35138T107 6653563 247000 247000 247000
FRANCE TELECOM COMMON 35177Q105 361900 4700 4700 2900 1800
FRONTIER CORP COMMON 35906P105 375200 6400 6400 400 6000
GTE CORP COMMON 362320103 1075875 14250 14250 13625 625
GANNETT INC COMMON 364730101 1070625 15000 15000 15000
GEERLINGS & WADE INC COMMON 368473104 96000 12000 12000 12000
GELTEX PHARMACEUTICALS COMMON 368538104 3180060 176670 176670 121258 55385
GENENTECH INC COMMON 368710307 205625 2500 2500 2500
GENERAL ELEC CO COMMON 369604103 10366168 91736 91736 66726 25010
GENERAL MTRS CORP COMMON 370442105 447480 6780 6780 2780 4000
GENZYME CORP GENL DIV COMMON 372917104 6588774 135851 135851 115151 20700
GENZYME CORP COMMON 372917609 107059 24297 24297 20598 3699
GILEAD SCIENCES INC COMMON 375558103 10073800 192800 192800 183900 8900
GILLETTE CO COMMON 375766102 460430 11230 11230 1090 10140
GLENBOROUGH RLTY TR INC COMMON 37803P105 302750 17300 17300 4800 12500
GLOBAL INDUSTRIES LTD COMMON 379336100 137094 10700 10700 7400 3300
-------- ------- ------- ------ ------ ------- ------ ------
COLUMN TOTALS 63177564 1605089 1605099 1310025 295074
</TABLE>
<PAGE>
<TABLE>
<CAPTION>
FORM 13F 6/30/99
REPORTING MANAGER: ESSEX INVESTMENT MGMT CO PAGE 12
- ------------------------------------------------------------------------------------------------------------------------------------
ITEM 1 ITEM 2 ITEM 3 ITEM 4 ITEM 5 ITEM 6 ITEM 7 ITEM 8
NAME OF ISSUER TITLE CUSIP FAIR SHARES OR INVESTMENT DISCRETION MANA- VOTING AUTHORITY
OF NUMBER MARKET PRINCIPAL SHARED GERS
CLASS VALUE AMOUNT SHARED- SHARED OTHER SOLE SHARED NONE
DEFINED (B) (C) (A) (B) (C)
- ------------------------------------------------------------------------------------------------------------------------------------
<S> <C> <C> <C> <C> <C> <C> <C> <C> <C> <C> <C>
GLOBAL MARINE INC COMMON 379352404 2564398 165445 165445 164045 1400
GLOBAL TELESYSTEMS GROUP COMMON 37936U104 147590910 1822110 1822110 474455 347655
GLOBESPAN SEMICONDUCTOR COMMON 379571102 34514925 868300 868300 656890 211410
GOLDMAN SACHS GROUP INC COMMON 38141G104 1881029 26035 26035 18055 7980
GOLF TR AMER INC COMMON 38168B103 882438 36110 36110 24550 11560
GOTO COM INC COMMON 38348T107 1048600 37450 37450 30145 7305
DEJA.COM INC COMMON 383990108 999999 277008 277008 277008
GREAT PLAINS SOFTWARE COMMON 39119E105 26973791 571630 571630 377980 193650
GUIDANT CORP COMMON 401698105 3115046 60930 60930 38940 21990
HALLIBURTON CO COMMON 406216101 12191255 269420 269420 246360 23060
HANDLEMAN CO DEL COMMON 410252100 3056484 258750 258750 228750 30000
HANGER ORTHOPEDIC GROUP COMMON 41043F208 401861 28325 28325 24325 4000
HANNAFORD BROS CO COMMON 410550107 444050 8300 8300 8300
HARMON INDS INC NEW COMMON 413136102 6067578 306250 306250 306250
HARRAHS ENTMT INC COMMON 413619107 836169 37900 37900 37900
HARTFORD FINL SVCS GROUP COMMON 416515104 5332387 91445 91445 80445 11000
CANAL PLUS COMMON 4171720 448964 1600 1600 1600
HASBRO INC COMMON 418056107 5238281 187500 187500 105170 82330
HELIX TECHNOLOGY CORP COMMON 423319102 2141808 89475 89475 82075 7400
--------- --------- ------- ------ ------ ------ ------ -------
COLUMN TOTALS 255729972 5143983 5143983 906235 1237748
</TABLE>
<PAGE>
<TABLE>
<CAPTION>
FORM 13F 6/30/99
REPORTING MANAGER: ESSEX INVESTMENT MGMT CO PAGE 13
- ------------------------------------------------------------------------------------------------------------------------------------
ITEM 1 ITEM 2 ITEM 3 ITEM 4 ITEM 5 ITEM 6 ITEM 7 ITEM 8
NAME OF ISSUER TITLE CUSIP FAIR SHARES OR INVESTMENT DISCRETION MANA- VOTING AUTHORITY
OF NUMBER MARKET PRINCIPAL SHARED GERS
CLASS VALUE AMOUNT SHARED- SHARED OTHER SOLE SHARED NONE
DEFINED (B) (C) (A) (B) (C)
- ------------------------------------------------------------------------------------------------------------------------------------
<S> <C> <C> <C> <C> <C> <C> <C> <C> <C> <C> <C>
HEWLETT PACKARD CO COMMON 428236103 20641796 205391 205391 147086 58305
HI/FN INC COMMON 428358105 1111425 14600 14600 14100 500
HIGH SPEED ACCESS CORP COMMON 42979U102 1704063 66500 66500 58000 8500
HOLLYWOOD ENTMT CORP COMMON 436141105 946825 48400 48400 38900 9500
HOME DEPOT INC COMMON 437076102 64764069 1005068 1005068 830679 174389
HONG KONG TELECOMMUNICAT COMMON 438579203 2550981 94700 94700 94700
HOUSEHOLD INTL INC COMMON 441815107 245734 5187 187 5187
IDT CORP COMMON 448947101 611875 27500 27500 15500 12000
HYSEQ COMMON 449163302 34688 10000 10000 10000
IMS HEALTH INC COMMON 449934108 5822813 186330 186330 116100 70230
IRT CORP COMMON 450052303 3973 15893 15893 15893
ISS GROUP INC COMMON 450306105 2913092 77168 77168 77168
IMMUNEX CORP NEW COMMON 452528102 637188 5000 5000 5000
INCO LTD COMMON 453258402 247500 13750 13750 3750 1000
INFINITY BROADCASTING CP COMMON 45662S102 8611704 291305 291305 260105 31200
INET TECHNOLOGIES INC COMMON 45662V105 2032440 84685 84685 68085 16600
INFOSPACE COM INC COMMON 45678T102 46930675 996525 996525 858400 140125
INKTOMI CORP COMMON 457277101 30692758 233405 233405 182140 51265
INPUT/OUTPUT INC COMMON 457652105 1890625 250000 250000 250000
--------- ------- ------- ------ ------ ------- ------ -------
192394222 3633407 3633407 2957732 675675
</TABLE>
<PAGE>
<TABLE>
<CAPTION>
FORM 13F 6/30/99
REPORTING MANAGER: ESSEX INVESTMENT MGMT CO PAGE 14
- ------------------------------------------------------------------------------------------------------------------------------------
ITEM 1 ITEM 2 ITEM 3 ITEM 4 ITEM 5 ITEM 6 ITEM 7 ITEM 8
NAME OF ISSUER TITLE CUSIP FAIR SHARES OR INVESTMENT DISCRETION MANA- VOTING AUTHORITY
OF NUMBER MARKET PRINCIPAL SHARED GERS
CLASS VALUE AMOUNT SHARED- SHARED OTHER SOLE SHARED NONE
DEFINED (B) (C) (A) (B) (C)
- ------------------------------------------------------------------------------------------------------------------------------------
<S> <C> <C> <C> <C> <C> <C> <C> <C> <C> <C> <C>
INSITUFORM TECHNOLS COMMON 457667103 2245324 103830 103830 103830
INKEEPERS USA TR COMMON 4576J0104 289500 28950 28950 12300 6650
INTEL CORP COMMON 458140100 987700 16600 16600 16600
INTERMEDIA COMMUNICATION COMMON 458801107 1179450 39315 39315 28715 0600
INTERNATIONAL BUS MACH COMMON 459200101 2154081 16666 16666 11266 5400
INTERNATIONAL TELECOMMUN COMMON 46047F104 1068800 66800 66800 61700 5100
INTERPUBLIC GROUP COS IN COMMON 460690100 1143450 13200 13200 7400 5800
INTERNET COM CORP COMMON 460967102 5015138 399215 399215 329505 9710
INTUIT COMMON 461202103 45412636 503885 503885 415510 8375
INVITROGEN CORP COMMON 46185R100 22718302 920235 920235 735855 4380
IONICS INC COMMON 462218018 1825000 50000 50000 50000
I2 TECHNOLOGIES INC COMMON 465754109 22606605 525735 525735 412185 3550
JDS FITEL INC COMMON 465934107 4130295 49500 49500 15200 4300
JAKKS PAC INC COMMON 47012E106 3256270 109225 109225 97325 1900
JAMESON INNS INC COMMON 470457102 254531 27150 27150 1150 6000
JOHN NUVEEN CO COMMON 478035108 213438 5000 5000 5000
JOHNSON & JOHNSON COMMON 478160104 11927972 121714 121714 72240 9474
JONES INTERCABLE INC COMMON 480206200 9585625 195626 195625 171950 3675
JUNIPER NETWORKS COMMON 48203R104 30127800 202200 202200 105715 6485
--------- ------- ------- ------ ------ ------- ------ ------
COLUMN TOTALS 166141916 3394845 3394845 2653446 741399
</TABLE>
<PAGE>
<TABLE>
<CAPTION>
FORM 13F 6/30/99
REPORTING MANAGER: ESSEX INVESTMENT MGMT CO PAGE 15
- ------------------------------------------------------------------------------------------------------------------------------------
ITEM 1 ITEM 2 ITEM 3 ITEM 4 ITEM 5 ITEM 6 ITEM 7 ITEM 8
NAME OF ISSUER TITLE CUSIP FAIR SHARES OR INVESTMENT DISCRETION MANA- VOTING AUTHORITY
OF NUMBER MARKET PRINCIPAL SHARED GERS
CLASS VALUE AMOUNT SHARED- SHARED OTHER SOLE SHARED NONE
DEFINED (B) (C) (A) (B) (C)
- ------------------------------------------------------------------------------------------------------------------------------------
<S> <C> <C> <C> <C> <C> <C> <C> <C> <C> <C> <C>
KLA-TENCOR CORP COMMON 482480100 1365619 21050 21050 20700 350
KESTREL SOLUTIONS COMMON 492990106 400000 125000 125000 125000
KEYCORP NEW COMMON 493267108 578250 18000 18000 18000
KIMBERLY CLARK CORP COMMON 494368103 456000 8000 8000 8000
KINDER MORGAN ENERGY PAR COMMON 494550106 514300 13900 13900 13900
KING PHARMACEUTICALS INC COMMON 495582108 29665946 1146510 1146510 941730 204780
KNIGHT/TRIMARK GROUP INC COMMON 499067106 88604025 1452525 1452525 1238345 214180
KOHLS CORP COMMON 500255104 211406 2750 2750 2050 700
KONINKLIJKE PHILIPS ELEC COMMON 500472204 1983707 19665 19665 16997 2668
KROGER CO COMMON 501044101 4975948 178110 178110 129100 49010
KROLL D GARA CO COMMON 501050108 344175 15600 15600 15600
KRONDS INC COMMON 501052104 18567731 408082 408082 401327 6755
LCA-VISION INC COMMON 501803209 386469 41500 41500 41500
LSI LOGIC CORP COMMON 502161102 1150819 249950 249950 11800 13150
LABOR READY INC COMMON 505401208 711750 21900 21900 2100 19800
LASER VISION CTRS INC COMMON 51807H100 11902275 188925 188925 163025 25900
LASON INC COMMON 51808R107 228275 4600 4600 2400 2200
LAUDER ESTEE COS INC COMMON 518439104 242605 4840 4840 2340 2500
LEGATO SYSTEMS INC COMMON 524651106 2806650 48600 48600 1200 47400
--------- ------- ------- ------ ------ ------- ------ ------
COLUMN TOTALS 165095950 3744507 3744507 2988514 755993
</TABLE>
<PAGE>
<TABLE>
<CAPTION>
FORM 13F 6/30/99
REPORTING MANAGER: ESSEX INVESTMENT MGMT CO PAGE 16
- ------------------------------------------------------------------------------------------------------------------------------------
ITEM 1 ITEM 2 ITEM 3 ITEM 4 ITEM 5 ITEM 6 ITEM 7 ITEM 8
NAME OF ISSUER TITLE CUSIP FAIR SHARES OR INVESTMENT DISCRETION MANA- VOTING AUTHORITY
OF NUMBER MARKET PRINCIPAL SHARED GERS
CLASS VALUE AMOUNT SHARED- SHARED OTHER SOLE SHARED NONE
DEFINED (B) (C) (A) (B) (C)
- ------------------------------------------------------------------------------------------------------------------------------------
<S> <C> <C> <C> <C> <C> <C> <C> <C> <C> <C> <C>
LEXMARK INTL GROUP INC COMMON 529771107 38267720 584240 584240 420340 163900
LIFECORE BIOMEDICAL INC COMMON 532187101 1352975 117650 117650 102750 14900
LILLY ELI & CO COMMON 532457108 348527 4866 4866 3846 1020
LINEAR TECHNOLOGY CORP COMMON 535678106 201750 3000 3000 3000
LINENS N THINGS INC COMMON 535679104 28500063 651430 651430 491645 159785
LIVING.COM SER B PFD COMMON 538990102 749986 79893 79893 79893
LOUISIANA PAC CORP COMMON 546347105 2391081 100150 100150 98850 1300
LOWES COS INC COMMON 548661107 896513 15815 15815 12325 3490
LUCENT TECHNOLOGIES INC COMMON 549463107 12969715 192322 192322 138623 53699
LYCOS INC COMMON 550818108 23274235 253325 253325 212310 41015
MCI WORLDCOM INC COMMON 552688106 87396899 1015505 1015505 772274 243231
MDSI MOBILE DATA SOLUTIO COMMON 55268N100 6891941 425757 425757 367457 58300
MGM GRAND INC COMMON 552953101 882000 18000 18000 18000
MKS INSTRUMENT INC COMMON 55306N104 2382138 127900 127900 120100 7800
MKC NETWORKS INC COMMON 55308N102 3192913 71350 71350 53625 17725
MPSI SYSTEMS (UNRESTR) COMMON 553412206 53813 20500 20500 20500
MACROVISION CORP COMMON 555904101 10254131 136950 136950 127250 9700
MACROMEDIA INC COMMON 556100105 2330025 66100 66100 66100
MAKER COMMUNICATIONS INC COMMON 560875106 27388190 883490 883490 745505 137985
--------- ------- ------- ------ ------ ------- ------ -------
COLUMN TOTALS 249724624 4768243 4768243 3754000 1014243
</TABLE>
<PAGE>
<TABLE>
<CAPTION>
FORM 13F 6/30/99
REPORTING MANAGER: ESSEX INVESTMENT MGMT CO PAGE 17
- ------------------------------------------------------------------------------------------------------------------------------------
ITEM 1 ITEM 2 ITEM 3 ITEM 4 ITEM 5 ITEM 6 ITEM 7 ITEM 8
NAME OF ISSUER TITLE CUSIP FAIR SHARES OR INVESTMENT DISCRETION MANA- VOTING AUTHORITY
OF NUMBER MARKET PRINCIPAL SHARED GERS
CLASS VALUE AMOUNT SHARED- SHARED OTHER SOLE SHARED NONE
DEFINED (B) (C) (A) (B) (C)
- ------------------------------------------------------------------------------------------------------------------------------------
<S> <C> <C> <C> <C> <C> <C> <C> <C> <C> <C> <C>
MAMAMEDIA INC SER D PFD COMMON 561994104 902988 167220 167220 74627 92593
MANDALAY RESORT GROUP COMMON 562567107 819956 38700 38700 38700
MARIMBA INC COMMON 56781Q109 1142265 21680 21680 19400 2280
MARINE DRILLING COS INC COMMON 568240204 1613756 117900 117900 102900 15000
MARSH & MCLENNAN COS INC COMMON 571748102 4669919 61700 61700 53600 8100
MATHSOFT INC COMMON 576798102 57500 20000 20000 20000
LOOKSMART, LTD SER C PFD COMMON 576990105 1500000 200000 200000 200000
MATTEL INC COMMON 577081102 391875 15000 15000 3000 12000
MAXIMUS INC COMMON 577933104 208438 7250 7250 6750 500
MCCORMICK & CO INC COMMON 579780206 526305 16675 16675 11275 5400
MCDERMOTT INTL INC COMMON 580037109 2252090 79720 79720 68520 10200
MCGRAW HILL COS INC COMMON 580645109 55774611 1034060 1034060 852190 181870
MEDIAONE GROUP INC COMMON 58440J104 17497834 235265 235265 189435 45830
MEDIAONE GROUP INC PFD CV 58440J203 337977 2256 2256 2256
MEDIA METRIX INC COMMON 58440X103 5887320 110560 110560 87265 23295
MEDIALINK WORLDWIDE INC COMMON 58445P105 473600 29600 29600 22800 6800
MEDIMMUNE INC COMMON 584699102 6287878 92810 92810 77535 15275
MEDQUIST INC COMMON 584949101 3231375 73860 73860 41000 32860
MEDTRONIC INC COMMON 585055106 34158311 438630 438630 377570 61060
--------- ------- ------- ------ ------ ------- ------ ------
COLUMN TOTALS 137733998 2762886 2762886 2027567 735319
</TABLE>
<PAGE>
<TABLE>
<CAPTION>
FORM 13F 6/30/99
REPORTING MANAGER: ESSEX INVESTMENT MGMT CO PAGE 18
- ------------------------------------------------------------------------------------------------------------------------------------
ITEM 1 ITEM 2 ITEM 3 ITEM 4 ITEM 5 ITEM 6 ITEM 7 ITEM 8
NAME OF ISSUER TITLE CUSIP FAIR SHARES OR INVESTMENT DISCRETION MANA- VOTING AUTHORITY
OF NUMBER MARKET PRINCIPAL SHARED GERS
CLASS VALUE AMOUNT SHARED- SHARED OTHER SOLE SHARED NONE
DEFINED (B) (C) (A) (B) (C)
- ------------------------------------------------------------------------------------------------------------------------------------
<S> <C> <C> <C> <C> <C> <C> <C> <C> <C> <C> <C>
MERCK & CO INC COMMON 589331107 2796278 37980 37980 7280 30700
MERCURY COMPUTER SYS COMMON 589378108 3929663 121850 121850 92635 29215
METROMEDIA FIBER NETWORK COMMON 591689104 16207453 450990 450990 380080 70910
METZLER GROUP INC COMMON 592903108 9609329 347849 347849 297134 50715
MICREL INC COMMON 594793101 1380840 18660 18660 10060 8600
MICROSOFT CORP COMMON 594918104 125386329 1390285 1390285 1129805 260480
MICROMUSE INC COMMON 595094103 70677863 1417100 1417100 1157585 259515
MILLENNIUM PHARMACEUTICA COMMON 599902103 4066200 112950 112950 82635 30315
MINNESOTA MNG & MFG CO COMMON 604059105 367224 4224 4224 470 3754
MIPS TECHNOLOGIES INC COMMON 604567107 42511694 886815 886815 742340 144475
MOBIL CORP COMMON 607059102 967355 9796 9796 2150 7646
MODEN MEDIA POPPE TYSON COMMON 607533106 304238 13300 13300 10800 2500
MONSANTO CO COMMON 611662107 24174270 611040 611040 516310 94730
MONTANA POWER COMPANY COMMON 612085100 37390028 530355 530355 371105 159250
MOTOROLA INC/CV/LYON COMMON 620076AE9 434688 250000 250000 250000
MUTUTAL RISK MGMT LTD COMMON 628351108 591906 17735 17735 10500 7235
NCO GROUP INC COMMON 628858102 2933600 77200 77200 77200
NTL INC COMMON 629407107 922206 10700 10700 10700
NASDAQ 100 TR COMMON 631100104 3953075 34300 34300 34300
--------- ------- ------- ------ ------ ------- ------ -------
COLUMN TOTALS 348604236 6344129 6343129 5183089 1160040
</TABLE>
<PAGE>
<TABLE>
<CAPTION>
FORM 13F 6/30/99
REPORTING MANAGER: ESSEX INVESTMENT MGMT CO PAGE 19
- ------------------------------------------------------------------------------------------------------------------------------------
ITEM 1 ITEM 2 ITEM 3 ITEM 4 ITEM 5 ITEM 6 ITEM 7 ITEM 8
NAME OF ISSUER TITLE CUSIP FAIR SHARES OR INVESTMENT DISCRETION MANA- VOTING AUTHORITY
OF NUMBER MARKET PRINCIPAL SHARED GERS
CLASS VALUE AMOUNT SHARED- SHARED OTHER SOLE SHARED NONE
DEFINED (B) (C) (A) (B) (C)
- ------------------------------------------------------------------------------------------------------------------------------------
<S> <C> <C> <C> <C> <C> <C> <C> <C> <C> <C> <C>
NATIONAL GOLF PPTYS INC. COMMON 63628G109 330650 13600 13600 5300 8300
NATIONAL RECORD MART INC. COMMON 637355108 614725 146800 146800 77700 69100
NATIONAL SEMICONDUCTOR C COMMON 637640103 21239086 839075 839075 691675 147400
NATIONWIDE FINL SVCS COMMON 638612101 230775 5100 5100 5100
NATURAL MICROSYSTEMS COMMON 638882100 1019363 106600 106600 70600 36000
NETBANK INC COMMON 640933107 1826850 48075 48075 47940 135
NETEGRITY INC COMMON 64110P107 1223475 74150 74150 35100 39050
NETGRAVITY INC COMMON 641114103 2470309 108585 108585 91100 17485
NETWORK APPLIANCE INC COMMON 64120L104 45181084 808610 808610 698710 109900
NETWORK SOLUTIONS INC DE COMMON 64121Q102 10242731 129450 129450 111350 18100
NEW ERA OF NETWORKS INC COMMON 644312100 246709 5615 5615 5615
NEW YORK TIMES CO COMMON 650111107 640538 17400 17400 17400
NEWBRIDGE NETWORKS CORP COMMON 650901101 2795219 97225 97225 69950 27275
NEWPARK RES INC COMMON 651718504 887500 100000 100000 100000
NEWS CORP LTD COMMON 652487802 533406 16900 16900 3400 13500
NEXTCARD INC COMMON 65332K107 59740860 1760320 1760320 1295550 464770
NEXTLINK COMMUNICATIONS COMMON 65333H707 2624322 35285 35285 27475 7810
NICOR INC COMMON 654086107 380625 10000 10000 10000
NIPPON TELEG & TEL CORP COMMON 654624105 3131250 50000 50000 50000
--------- ------- ------- ------ ------ ------- ------ ------
COLUMN TOTALS 155359476 4372790 4372790 3413965 958825
</TABLE>
<PAGE>
<TABLE>
<CAPTION>
FORM 13F 6/30/99
REPORTING MANAGER: ESSEX INVESTMENT MGMT CO PAGE 20
- ------------------------------------------------------------------------------------------------------------------------------------
ITEM 1 ITEM 2 ITEM 3 ITEM 4 ITEM 5 ITEM 6 ITEM 7 ITEM 8
NAME OF ISSUER TITLE CUSIP FAIR SHARES OR INVESTMENT DISCRETION MANA- VOTING AUTHORITY
OF NUMBER MARKET PRINCIPAL SHARED GERS
CLASS VALUE AMOUNT SHARED- SHARED OTHER SOLE SHARED NONE
DEFINED (B) (C) (A) (B) (C)
- ------------------------------------------------------------------------------------------------------------------------------------
<S> <C> <C> <C> <C> <C> <C> <C> <C> <C> <C> <C>
NOBEL AFFILIATES INC COMMON 654894104 50968638 1805200 1805200 1540930 267270
NOKIA CORP COMMON 654902204 35986810 393030 393030 270605 122425
NOBLE DRILLING CORP COMMON 655042109 17278636 877645 877645 722995 154650
NORTEL NETWORKS CORP COMMON 656569100 665591 7667 7667 7667
NINTENDO COMMON 6639550 2079874 14800 14800 10200 4600
NORTHERN TR CORP COMMON 665859104 658436 6788 6788 1000 5788
NORTHPOINT COMMUNICATION COMMON 666610100 66049305 1809570 1809570 1479335 330235
NORTHWEST AIRLINES CP COMMON 667280101 2600000 80000 80000 69500 10500
OFFICEMAX INC COMMON 67622M108 120000 10000 10000 10000
SOFTBANK CORP COMMON 6770620 11051292 54625 54625 37325 17300
OMNICON GROUP INC COMMON 681919106 704000 8800 8800 7600 1200
ONYX SOFTWARE CORP COMMON 6B3402101 283288 13100 13100 7900 5200
OPTICAL COATING LAB INC COMMON 683829105 10459815 125080 125080 104880 20200
ORACLE CORP COMMON 68389X105 708345 19080 19080 12900 6180
O'REILLY AUTOMOTIVE COMMON 686091109 11542676 229135 229135 185535 43600
OSTEOTECH INC COMMON 688582105 1649991 57391 57391 45129 12262
OUTBACK STEAKHOUSE INC COMMON 689699102 53466691 1360043 1360043 1081498 278545
PE CORP - BIO GROUP COMMON 693325102 95898870 835720 835720 691410 144310
PE CORP - CELERA GEN COMMON 69332S201 301088 18600 18600 16100 2500
--------- ------- ------- ------ ------ ------- ------ -------
COLUMN TOTALS 362483345 7729274 7729274 6284842 1444432
</TABLE>
<PAGE>
<TABLE>
<CAPTION>
FORM 13F 6/30/99
REPORTING MANAGER: ESSEX INVESTMENT MGMT CO PAGE 21
- ------------------------------------------------------------------------------------------------------------------------------------
ITEM 1 ITEM 2 ITEM 3 ITEM 4 ITEM 5 ITEM 6 ITEM 7 ITEM 8
NAME OF ISSUER TITLE CUSIP FAIR SHARES OR INVESTMENT DISCRETION MANA- VOTING AUTHORITY
OF NUMBER MARKET PRINCIPAL SHARED GERS
CLASS VALUE AMOUNT SHARED- SHARED OTHER SOLE SHARED NONE
DEFINED (B) (C) (A) (B) (C)
- ------------------------------------------------------------------------------------------------------------------------------------
<S> <C> <C> <C> <C> <C> <C> <C> <C> <C> <C> <C>
P F CHANGS CHINA BISTRO COMMON 69333Y10B 9250202 427755 427775 343955 83800
PMC-SIERRA INC COMMON 69344F106 1591313 27000 27000 27000
PARAMETRIC TECHNOLOGY CO COMMON 699173100 2748013 198055 198055 171325 26730
PEGASUS SYSTEMS INC COMMON 705906105 318219 8500 8500 7500 1000
PEPSICO INC COMMON 713448108 281142 7267 7267 2000 5267
PEREGRINE SYSTEMS INC COMMON 71366Q101 4006479 155970 155970 114470 41500
PERITUS SOFTWARE SVC COMMON 714006103 1715 10088 10088 10088
PEROT SYS CORP COMMON 714265105 2683763 90975 90975 78075 12900
PERSISTENCE SOFTWARE INC COMMON 715329105 5804250 426000 426000 312325 113675
PETROLEUM GEO-SVCS A/S COMMON 716597108 18479138 1242295 1242295 1046095 196200
PHARMACYCLICS INC COMMON 716933106 268800 9600 9600 9600
PFIZER INC COMMON 717081103 13369395 122655 122655 80605 42050
PHELPS DODGE CORP COMMON 717265102 563631 9100 9100 6600 2500
PHONE COM INC COMMON 71920Q100 47535320 848845 848845 682320 166525
PINNACLE SYS INC COMMON 723481107 5272400 156800 156800 136800 20000
PIXAR INC COMMON 725811103 4446188 103100 103100 96900 6200
PLAYBOY ENTERPRISES INC COMMON 728117300 4917648 185135 185135 178735 6400
POLAROID CORP COMMON 731095105 10357050 376620 376620 354995 21625
POLICY MGMT SYS CORP COMMON 731108106 1860000 62000 62000 27490 34510
--------- ------- ------- ------ ------ ------- ------ ------
COLUMN TOTALS 133754666 4467760 4467760 3649790 817970
</TABLE>
<PAGE>
<TABLE>
<CAPTION>
FORM 13F 6/30/99
REPORTING MANAGER: ESSEX INVESTMENT MGMT CO PAGE 22
- ------------------------------------------------------------------------------------------------------------------------------------
ITEM 1 ITEM 2 ITEM 3 ITEM 4 ITEM 5 ITEM 6 ITEM 7 ITEM 8
NAME OF ISSUER TITLE CUSIP FAIR SHARES OR INVESTMENT DISCRETION MANA- VOTING AUTHORITY
OF NUMBER MARKET PRINCIPAL SHARED GERS
CLASS VALUE AMOUNT SHARED- SHARED OTHER SOLE SHARED NONE
DEFINED (B) (C) (A) (B) (C)
- ------------------------------------------------------------------------------------------------------------------------------------
<S> <C> <C> <C> <C> <C> <C> <C> <C> <C> <C> <C>
POLYCOM INC COMMON 73172K104 19212375 492625 492625 412250 80375
PORTAL SOFTWARE INC COMMON 736126103 30350897 655350 655350 529655 125695
POTOMAC ELEC PWR CO COMMON 737679100 1476732 50165 50165 33040 17125
POWER INTEGRATIONS INC COMMON 739276103 670922 9175 9175 4300 4875
POWERTEL INC COMMON 73936C109 3030819 101450 101450 70100 31350
PRENTISS PPTYS TR COMMON 740706106 509709 21575 21575 7950 13625
PREVIEW TRAVEL INC COMMON 74137R101 1096875 50000 50000 50000
PRICELINE COM INC COMMON 741503106 63671471 550970 550970 430900 120070
PROBUSINESS SERVICES INC COMMON 742674104 5371564 149730 149730 117625 32105
PROCTER & GAMBLE CO COMMON 742718109 1326612 14864 14864 40 14824
PROFIT RECOVERY GROUP IN COMMON 743168106 5152331 108900 108900 108900
PROGRESSIVE CORP OHIO COMMON 743315103 4830675 33315 33315 29015 4300
DYAX CORP PFD CV 743997892 102838 28944 28944 26944
PROXIM INC COMMON 744284100 1490600 25700 25700 25700
QLT PHOTOTHERAPEUTICS IN COMMON 746927102 24580325 446915 446915 374070 72845
QRS CORP COMMON 74726X105 2620800 33600 33600 27000 6600
QLOGIC CORP COMMON 747277101 17477460 132405 132405 86540 43865
QUINTILES TRANSNATIONAL COMMON 748767100 4300590 102395 102395 77170 25225
QWEST COMMUNICATIONS INT COMMON 749121109 105505645 3191097 3191097 2637710 553387
--------- ------- ------- ------ ------ ------- ------ -------
COLUMN TOTALS 292779240 6199175 6199175 5052909 1146266
</TABLE>
<PAGE>
<TABLE>
<CAPTION>
FORM 13F 6/30/99
REPORTING MANAGER: ESSEX INVESTMENT MGMT CO PAGE 23
- ------------------------------------------------------------------------------------------------------------------------------------
ITEM 1 ITEM 2 ITEM 3 ITEM 4 ITEM 5 ITEM 6 ITEM 7 ITEM 8
NAME OF ISSUER TITLE CUSIP FAIR SHARES OR INVESTMENT DISCRETION MANA- VOTING AUTHORITY
OF NUMBER MARKET PRINCIPAL SHARED GERS
CLASS VALUE AMOUNT SHARED- SHARED OTHER SOLE SHARED NONE
DEFINED (B) (C) (A) (B) (C)
- ------------------------------------------------------------------------------------------------------------------------------------
<S> <C> <C> <C> <C> <C> <C> <C> <C> <C> <C> <C>
R & B FALCON CORP COMMON 74912E101 17798672 1898525 1898525 1532225 366300
RCN CORP COMMON 749361101 55192211 1325939 1325939 1078063 247876
RF MICRODEVICES INC COMMON 749941100 4716300 63200 63200 63200
RADIO ONE INC COMMON 75040P108 218550 4700 4700 4700
RAMP NETWORKS INC COMMON 751567108 5584738 390200 390200 346600 43600
RANGER OIL LTD COMMON 752805101 57769 11700 11700 11700
RARE HOSPITALITY INTL COMMON 753820109 1285710 50420 50420 50420
RATIONAL SOFTWARE CORP COMMON 75409P202 11701376 355260 355260 253760 101500
REALNETWORKS INC COMMON 75605L104 15848138 230100 230100 158200 71900
REALTY INFORMATION GROUP COMMON 75612B107 20387363 468675 468675 386025 82650
REDBACK NETWORKS INC COMMON 757209101 33205631 264455 264455 186505 77950
REINSURANCE GROUP AMER I COMMON 759351208 402000 12000 12000 12000
RESEARCH IN MOTION LTD COMMON 760975102 1012500 50000 50000 50000
RESOLUTION TECH INC COMMON 761990100 0 250000 250000 200000 50000
RHYTHMS NETCONNECTIONS I COMMON 762430205 100299925 1718200 1718200 1431975 286225
ROGERS CANTEL MOBILE COM COMMON 775102205 1050356 63900 63900 63900
ROYAL DUTCH PETE CO COMMON 780257804 1512998 25112 25112 6461 18651
SBC COMMUNICATIONS INC COMMON 78387G103 1982788 34186 34186 4200 29986
S3 INC COMMON 784849101 928927 102150 102150 48200 53950
--------- ------- ------- ------ ------ ------- ------ -------
COLUMN TOTALS 273185950 7318722 7318722 5688134 1430588
</TABLE>
<PAGE>
<TABLE>
<CAPTION>
FORM 13F 6/30/99
REPORTING MANAGER: ESSEX INVESTMENT MGMT CO PAGE 24
- ------------------------------------------------------------------------------------------------------------------------------------
ITEM 1 ITEM 2 ITEM 3 ITEM 4 ITEM 5 ITEM 6 ITEM 7 ITEM 8
NAME OF ISSUER TITLE CUSIP FAIR SHARES OR INVESTMENT DISCRETION MANA- VOTING AUTHORITY
OF NUMBER MARKET PRINCIPAL SHARED GERS
CLASS VALUE AMOUNT SHARED- SHARED OTHER SOLE SHARED NONE
DEFINED (B) (C) (A) (B) (C)
- ------------------------------------------------------------------------------------------------------------------------------------
<S> <C> <C> <C> <C> <C> <C> <C> <C> <C> <C> <C>
SAFEGAURD SCIENTIFICS INC COMMON 786449108 13704075 217525 217525 176975 49550
SAFEWAY INC COMMON 786514208 6471383 130735 130735 71365 59370
SBS BROADCASTING SA BND CV 805906ABO 483600 390000 390000 390000
SCHERING PLOUGH CORP COMMON 806605101 4132800 78720 78720 65620 13100
SCHLUMBERGER LTD COMMON 806857108 82520531 1295710 1295710 1100075 95635
SCHOOL SPECIALITY INC COMMON 807863105 4555727 283625 283625 207625 76000
SCIENT CORP COMMON 80864H109 4176463 87810 87810 79110 8700
SEAGRAM LTD COMMON 811850106 23742745 471320 471320 444000 27320
SEPRACOR INC COMMON 817315104 33132531 407785 407785 331295 76490
SEROLOGICALS CORP COMMON 817523103 3704407 455927 455927 422955 32972
SIEBEL SYSTEMS INC COMMON 826170102 2128631 32100 32100 14100 18000
SILICON STORAGE TECHNOLOGY COMMON 827057100 1895195 253750 253750 168300 85450
SILVERSTREAM SER D PFD COMMON 825990101 3249998 342105 342105 57530 64575
SILVERSTREAM SOFTWARE COMMON 828995100 4328020 455581 455581 455581
SINCLAIR BROADCAST GROUP COMMON 829226109 245625 15000 15000 15000
SMITH INTL INC COMMON 832110100 14382156 331100 331100 260850 70250
SNYDER COMMUNICATIONS INC COMMON 832914105 1294444 39525 39525 35325 4200
SOFTECH INC COMMON 834021107 71688 31000 31000 31000
SOFTWORKS INC COMMON 83404P102 825000 75000 75000 75000
--------- ------- ------- ------ ------ ------- ------ -------
COLUMN TOTALS 205045018 5394318 5394318 4346706 1047612
</TABLE>
<PAGE>
<TABLE>
<CAPTION>
FORM 13F 6/30/99
REPORTING MANAGER: ESSEX INVESTMENT MGMT CO PAGE 25
- ------------------------------------------------------------------------------------------------------------------------------------
ITEM 1 ITEM 2 ITEM 3 ITEM 4 ITEM 5 ITEM 6 ITEM 7 ITEM 8
NAME OF ISSUER TITLE CUSIP FAIR SHARES OR INVESTMENT DISCRETION MANA- VOTING AUTHORITY
OF NUMBER MARKET PRINCIPAL SHARED GERS
CLASS VALUE AMOUNT SHARED- SHARED OTHER SOLE SHARED NONE
DEFINED (B) (C) (A) (B) (C)
- ------------------------------------------------------------------------------------------------------------------------------------
<S> <C> <C> <C> <C> <C> <C> <C> <C> <C> <C> <C>
SONIC CORP COMMON 835451105 1467146 44970 44970 44970
SONY CORP COMMON 835699307 93416433 846355 846355 706400 139955
WOMEN.COM SER E PFD COMMON 837990100 125400 12540 12540 10178 2362
SPRINT CORP COMMON 852061100 8313050 156850 156850 119870 36980
SPRINT CORP COMMON 852061506 1122473 19692 19692 14700 4992
STAMPS COM INC COMMON 852857101 4877250 278700 278700 211740 66960
STAPLES INC COMMON 855030102 85056160 2749290 2749290 2335916 413374
STARBUCKS CORP COMMON 855244109 4235998 112772 112772 53220 59552
STARMEDIA NETWORK INC COMMON 855546107 27938301 435685 435685 335535 100150
STATE STR CORP COMMON 857477103 6619892 77539 77539 68205 9334
STERIGENICS INTL INC COMMON 85915R105 4788777 181565 181565 130605 50960
STMICROELECTRONICS N V COMMON 861012102 1102069 15900 15900 5700 10200
STUDENT ADVANTAGE INC COMMON 86386Q105 1399350 147300 147300 139200 8100
SUNGARD DATA SYS INC COMMON 867363103 229632 6656 6656 6656
SYMBOL TECHNOLOGIES INC COMMON 871508107 13118945 355768 355768 319393 36375
SYNIX SYS INC COMMON 871535100 256250 25000 25000 25000
TBA ENTMT CORP COMMON 872173109 306188 71000 71000 71000
TD WATERHOUSE GRP INC COMMON 872362108 1875000 75000 75000 62675 12325
TJX CDS INC NEW COMMON 872540109 1821528 54680 54680 35830 16850
--------- ------- ------- ------ ------ ------- ------ ------
COLUMN TOTALS 258069841 5667262 5667262 4690137 977125
<CAPTION>
- ----------------------------------------------------------------------------------------
ITEM 1 ITEM 7 ITEM 8
NAME OF ISSUER MANA- VOTING AUTHORITY
GERS SOLE SHARED NONE
(A) (B) (C)
- ----------------------------------------------------------------------------------------
<S> <C> <C> <C> <C>
SONIC CORP
SONY CORP
WOMEN.COM SER E PFD
SPRINT CORP
SPRINT CORP
STAMPS COM INC
STAPLES INC
STARBUCKS CORP
STARMEDIA NETWORK INC
STATE STR CORP
STERIGENICS INTL INC
STMICROELECTRONICS N V
STUDENT ADVANTAGE INC
SUNGARD DATA SYS INC
SYMBOL TECHNOLOGIES INC
SYNIX SYS INC
TBA ENTMT CORP
TD WATERHOUSE GRP INC
TJX CDS INC NEW
</TABLE>
<PAGE>
<TABLE>
<CAPTION>
FORM 13F 6/30/99
REPORTING MANAGER: ESSEX INVESTMENT MGMT CO PAGE 26
- ------------------------------------------------------------------------------------------------------------------------------------
ITEM 1 ITEM 2 ITEM 3 ITEM 4 ITEM 5 ITEM 6 ITEM 7 ITEM 8
NAME OF ISSUER TITLE CUSIP FAIR SHARES OR INVESTMENT DISCRETION MANA- VOTING AUTHORITY
OF NUMBER MARKET PRINCIPAL SHARED GERS
CLASS VALUE AMOUNT SHARED- SHARED OTHER SOLE SHARED NONE
DEFINED (B) (C) (A) (B) (C)
- ------------------------------------------------------------------------------------------------------------------------------------
<S> <C> <C> <C> <C> <C> <C> <C> <C> <C> <C> <C>
TSI INTERNATIONAL SOFTWA COMMON 872679101 7142328 251712 251712 207562 44150
TLC THE LASER CTR INC COMMON 872934104 23709840 493955 493955 403880 90075
TMP WORLDWIDE INC COMMON 872941109 2781300 43800 43800 41800 2000
TANDY CORP COMMON 875382103 2669064 54610 54610 38560 16050
TELECOM SEMICONDUCTOR INC COMMON 87921P107 102988 10700 10700 5000 5700
TELEBANC FINANCIAL CORP COMMON 87925R109 11743575 303060 303060 254260 48800
TELECOMUNICACOES BRASILE COMMON 879287100 9059 144950 144950 128350 16600
TELECOMUNICACOES BRASILE COMMON 879287308 12672000 140800 140800 124200 16600
TELEFONOS DE MEXICO SA COMMON 879403780 404063 5000 5000 5000
TELESYSTEM INTL WIRELESS COMMON 879946101 13934500 768800 768800 580600 188200
TENFOLD CORP COMMON 88033A103 18249424 574785 574785 472115 102670
TERADYNE INC COMMON 880770102 76959297 1100478 1100478 925260 175218
TEXACO INC COMMON 881694103 355538 5700 5700 500 5200
TEXAS INSTRS INC COMMON 882508104 40134240 278710 278710 234205 44505
TICKETMASTER ONLINE-CITY COMMON 88633P203 205700 6800 6800 4000 2800
TIME WARNER INC COMMON 887315109 34477993 474740 474740 351180 123560
TIME WARNER TELECOM INC COMMON 887319101 11771825 405925 405925 344045 61880
TIMES MIRROR CO NEW COMMON 887364107 839276 14165 14165 6790 7375
TOSCO CORP COMMON 891490302 268453 10350 10350 8650 1700
--------- -------- ------- ------ ------ ------- ------ ------
COLUMN TOTALS 260430461 5089040 5089040 4130957 958083
</TABLE>
<PAGE>
<TABLE>
<CAPTION>
FORM 13F 6/30/99
REPORTING MANAGER: ESSEX INVESTMENT MGMT CO PAGE 27
- ------------------------------------------------------------------------------------------------------------------------------------
ITEM 1 ITEM 2 ITEM 3 ITEM 4 ITEM 5 ITEM 6 ITEM 7 ITEM 8
NAME OF ISSUER TITLE CUSIP FAIR SHARES OR INVESTMENT DISCRETION MANA- VOTING AUTHORITY
OF NUMBER MARKET PRINCIPAL SHARED GERS
CLASS VALUE AMOUNT SHARED- SHARED OTHER SOLE SHARED NONE
DEFINED (B) (C) (A) (B) (C)
- ------------------------------------------------------------------------------------------------------------------------------------
<S> <C> <C> <C> <C> <C> <C> <C> <C> <C> <C> <C>
TRANSWITCH CORP COMMON 894065101 1167794 24650 24650 16300 8350
TRIDENT MICROSYSTEMS INC COMMON 895919108 2330869 253700 253700 167200 86500
TRIBUNE CO NEW COMMON 896047107 1315588 15100 15100 15100
TUESDAY MORNING CORP COMMON 899035505 510000 20000 20000 20000
TWEETER HOME ENTMT GROUP COMMON 901167106 15759268 401510 401510 337530 63980
TYCO INTL LTD COMMON 902124106 20427153 215590 215590 155090 60500
USA NETWORKS INC COMMON 902984103 300938 7500 7500 7500
U S G CORP COMMON 903293405 520800 9300 9300 2700 6600
ULTRAMAR DIAMOND SHAMROC COMMON 904000106 287925 13200 13200 13200
UNIPHASE CORP COMMON 909149106 117511400 707900 707900 581910 125990
UNITED INTL HLDGS INC COMMON 910734102 6868333 101565 101565 76565 25000
UNITED PAN-EUROPE COMMUN COMMON 911300200 15322759 277335 277335 245685 31650
UNITED TECHNOLOGIES CORP COMMON 913017109 11291328 156824 156824 129174 27650
UNIVISION COMMUNICATIONS COMMON 914906102 351000 5400 5400 2800 2600
USINTERNETWORKING INC COMMON 917311805 4527600 107800 107800 96405 11395
VARCO INTL INC COMMON 922126107 11179638 1033955 1033955 836555 197400
VASTAR RESOURCES LTD COMMON 922380100 12181232 232300 232300 169260 63040
VERITAS SOFTWARE CO COMMON 923436109 27423551 288859 288859 261854 27005
VERISIGN INC COMMON 92343E102 98424619 1141155 1141155 899100 242055
--------- ------- ------- ------ ------ ------- ------ ------
COLUMN TOTALS 347701792 5013643 5013643 4033928 979715
</TABLE>
<PAGE>
<TABLE>
<CAPTION>
FORM 13F 6/30/99
REPORTING MANAGER: ESSEX INVESTMENT MGMT CO PAGE 28
- ------------------------------------------------------------------------------------------------------------------------------------
ITEM 1 ITEM 2 ITEM 3 ITEM 4 ITEM 5 ITEM 6 ITEM 7 ITEM 8
NAME OF ISSUER TITLE CUSIP FAIR SHARES OR INVESTMENT DISCRETION MANA- VOTING AUTHORITY
OF NUMBER MARKET PRINCIPAL SHARED GERS
CLASS VALUE AMOUNT SHARED- SHARED OTHER SOLE SHARED NONE
DEFINED (B) (C) (A) (B) (C)
- ------------------------------------------------------------------------------------------------------------------------------------
<S> <C> <C> <C> <C> <C> <C> <C> <C> <C> <C> <C>
VERISITY LTD SER D PFD COMMON 923991103 500000 67884 67884 67884
VERTICALNET INC COMMON 92532L107 19942125 189925 189925 139795 50130
VIACOM INC/CL B COMMON 925524308 28329620 643855 643855 529190 114665
VIATEL INC COMMON 925529208 30381866 541325 541325 432525 108800
VIANT CORP COMMON 92553N107 2562700 73220 73220 52500 20720
VIGNETTE CORP COMMON 926734104 10650000 142000 142000 117200 24800
VISHAY INTERTECHNOLOGY I COMMON 928298108 1786050 85050 85050 56400 28650
VISIBLE GENETICS INC COMMON 92829S104 1612500 100000 100000 100000
VISX INC DEL COMMON 92844S105 104371501 1318030 1318030 1072905 245125
VITESSE SEMECONDUCTOR CO COMMON 928497106 14876375 220595 220595 177845 42750
VOICESTREAM WIRELESS COR COMMON 928615103 4235766 148950 148950 116750 30200
WAL MART STORES INC COMMON 931142103 53886420 1116817 1116817 994305 122512
WALGREEN CO COMMON 931422109 545769 187080 187080 129050 58040
WARNER LAMBERT CO COMMON 934488107 11226246 162405 162405 127180 35225
WASHINGTON MUTUAL INC COMMON 939322103 458756 12900 12900 12900
WASTE MGMT INC DEL COMMON 94106L109 566256 10535 10535 5058 5477
WATERS CORP COMMON 941848103 32381281 609530 609530 533530 76000
WATSON PHARMACEUTICALS COMMON 942683103 358659 10230 10230 8230 2000
WAVE SYSTEMS CORP COMMON 943526103 475000 25000 25000 25000
--------- ------- ------- ------ ------ ------- ------ -------
COLUMN TOTALS 324096920 5665341 5665341 4632363 1032978
</TABLE>
<PAGE>
<TABLE>
<CAPTION>
FORM 13F 6/30/99
REPORTING MANAGER: ESSEX INVESTMENT MGMT CO PAGE 29
- ------------------------------------------------------------------------------------------------------------------------------------
ITEM 1 ITEM 2 ITEM 3 ITEM 4 ITEM 5 ITEM 6 ITEM 7 ITEM 8
NAME OF ISSUER TITLE CUSIP FAIR SHARES OR INVESTMENT DISCRETION MANA- VOTING AUTHORITY
OF NUMBER MARKET PRINCIPAL SHARED GERS
CLASS VALUE AMOUNT SHARED- SHARED OTHER SOLE SHARED NONE
DEFINED (B) (C) (A) (B) (C)
- ------------------------------------------------------------------------------------------------------------------------------------
<S> <C> <C> <C> <C> <C> <C> <C> <C> <C> <C> <C>
WEATHERFORD INTL INC COMMON 947074100 1604175 43800 43800 41800 2000
WEEKS CORP COMMON 94856P102 237900 7800 7800 4300 3500
WELLS FARGO & CO NEW COMMON 949746101 282150 6600 6600 6600
WILDFIRE COMM WRTS COMMON 967990102 0 400000(W) 400000 90000 310000
WILDFIRE COMMUNICATIONS COMMON 967991100 2000000 400000 400000 90000 310000
WILLIAMS COS INC DEL COMMON 969457100 120862902 2839657 2839657 334632 505025
WINSTAR COMMUNICATIONS COMMON 975515107 131079049 2688801 2688801 186160 502641
WOMEN.COM NETWORKS COMMON 978990109 1823700 182370 182370 148020 34350
WORLDPORT COMMUNICATIONS COMMON 98155J105 2662500 600000 600000 510800 89200
WORLDGATE COMMUNICATIONS COMMON 98156L307 3687181 71945 71945 56835 15110
XILINX INC COMMON 983919101 23374603 408290 408290 335840 72450
XEROX CORP COMMON 984121103 13447291 227679 227679 179019 48660
YAHOO INC COMMON 984332106 117550118 682439 682439 513914 168525
YOUBET COM INC COMMON 987413101 1259841 110150 110150 54350 55800
YOUNG & RUBICAM INC COMMON 987425105 6438494 141700 141700 141700
YOUNG BROADCASTING INC COMMON 987434107 272400 6400 6400 6400
ZIFF-DAVIS INC COMMON 989511209 1202890 46265 46265 40405 5860
ZONAGEN INC COMMON 98975L108 793188 85750 85750 54850 30900
AMDOCS LTD COMMON G02602103 67586951 2970855 2970855 510470 460385
--------- -------- -------- ------ ------ ------ ------ -------
COLUMN TOTALS 496165331 11920501 11920501 299695 2620806
</TABLE>
<PAGE>
<TABLE>
<CAPTION>
FORM 13F 6/30/99
REPORTING MANAGER: ESSEX INVESTMENT MGMT CO PAGE 30
- ------------------------------------------------------------------------------------------------------------------------------------
ITEM 1 ITEM 2 ITEM 3 ITEM 4 ITEM 5 ITEM 6 ITEM 7 ITEM 8
NAME OF ISSUER TITLE CUSIP FAIR SHARES OR INVESTMENT DISCRETION MANA- VOTING AUTHORITY
OF NUMBER MARKET PRINCIPAL SHARED GERS
CLASS VALUE AMOUNT SHARED- SHARED OTHER SOLE SHARED NONE
DEFINED (B) (C) (A) (B) (C)
- ------------------------------------------------------------------------------------------------------------------------------------
<S> <C> <C> <C> <C> <C> <C> <C> <C> <C> <C> <C>
GEMSTAR INTL GROUP LTD COMMON G3788V106 44367064 679955 679955 531825 148130
GLOABL CROSSING LTD COMMON G3921A100 1681173 39441 39441 33710 5731
RSL COMMUNICATIONS LTD COMMON G7702U102 25784409 1335115 1335115 1073505 261610
SANTA FE INTL CORP COMMON G7805C108 22908230 996010 996010 835660 160350
AUDIOCODES LTD COMMON M15342104 3865320 143160 143160 127560 15600
BACKWEB TECHNOLOGIES LTD COMMON M15633106 1340828 48980 48980 37850 11130
ASM LITHOGRAPHY HLDG N V COMMON N07059111 9054094 152490 152490 134950 17540
ROYAL CARIBBEAN CRUISE COMMON V7780T103 9078125 207500 207500 206900 600
PACIFIC INTERNET LTD COMMON Y66183107 344653 7275 7275 5375 1900
----------- --------- --------- ------ ------ --------- ------ --------
COLUMN TOTALS 118423895 3609926 3609926 2987335 622591
----------- --------- --------- ------ ------ --------- ------ --------
REPORT TOTALS 67473666714 141913785 141913785 112216010 29697775
=========== ========= ========= ====== ====== ========= ====== ========
</TABLE>
