The Securities and Exchange Commission has not necessarily reviewed the information in this filing and has not determined if it is accurate and complete.
The reader should not assume that the information is accurate and complete.

UNITED STATES SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549
FORM 13F

FORM 13F INFORMATION TABLE
OMB APPROVAL
OMB Number: 3235-0006
Estimated average burden
hours per response: 23.8
COLUMN 1 COLUMN 2 COLUMN 3 COLUMN 4 COLUMN 5 COLUMN 6 COLUMN 7 COLUMN 8
VALUE SHRS OR SH/ PUT/ INVESTMENT OTHER VOTING AUTHORITY
NAME OF ISSUER TITLE OF CLASS CUSIP (x$1000) PRN AMT PRN CALL DISCRETION MANAGER SOLE SHARED NONE
3M CO COM 88579Y101 625 4,580 SH   SOLE   4,060 0 520
AAON INC COM PAR $0.004 000360206 77,939 1,612,978 SH   SOLE   1,609,411 0 3,567
ABBOTT LABS COM 002824100 709 8,990 SH   SOLE   8,990 0 0
ABBVIE INC COM 00287Y109 605 7,935 SH   SOLE   7,935 0 0
ACI WORLDWIDE INC COM 004498101 66,391 2,749,111 SH   SOLE   2,729,111 0 20,000
ADOBE INC COM 00724F101 398 1,250 SH   SOLE   1,080 0 170
ALBANY INTL CORP CL A 012348108 39,370 831,811 SH   SOLE   829,958 0 1,853
ALIGN TECHNOLOGY INC COM 016255101 328 1,887 SH   SOLE   1,887 0 0
ALPHABET INC CAP STK CL A 02079K305 238 205 SH   SOLE   145 0 60
ALPHABET INC CAP STK CL C 02079K107 238 205 SH   SOLE   145 0 60
ALTAIR ENGR INC COM CL A 021369103 53,870 2,032,827 SH   SOLE   2,014,077 0 18,750
AMGEN INC COM 031162100 270 1,330 SH   SOLE   1,330 0 0
ANSYS INC COM 03662Q105 9,219 39,658 SH   SOLE   36,188 0 3,470
APPLE INC COM 037833100 631 2,480 SH   SOLE   1,560 0 920
AXON ENTERPRISE INC COM 05464C101 62,607 884,661 SH   SOLE   871,581 0 13,080
BALCHEM CORP COM 057665200 83,592 846,760 SH   SOLE   838,852 0 7,908
BIOLIFE SOLUTIONS INC COM NEW 09062W204 290 30,560 SH   SOLE   30,560 0 0
BIO-TECHNE CORP COM 09073M104 66,581 351,128 SH   SOLE   346,451 0 4,677
BLACKBAUD INC COM 09227Q100 59,160 1,064,981 SH   SOLE   1,053,812 0 11,169
BLACKLINE INC COM 09239B109 81,451 1,548,212 SH   SOLE   1,544,837 0 3,375
BOTTOMLINE TECH DEL INC COM 101388106 73,284 1,999,564 SH   SOLE   1,984,009 0 15,555
BRIGHT HORIZONS FAM SOL IN D COM 109194100 12,388 121,454 SH   SOLE   110,509 0 10,945
CANTEL MEDICAL CORP COM 138098108 27,210 757,939 SH   SOLE   756,293 0 1,646
CAREDX INC COM 14167L103 574 26,305 SH   SOLE   26,305 0 0
CASELLA WASTE SYS INC CL A 147448104 76,558 1,960,005 SH   SOLE   1,937,775 0 22,230
CHEMBIO DIAGNOSTICS INC COM NEW 163572209 631 123,155 SH   SOLE   123,155 0 0
CHEVRON CORP NEW COM 166764100 215 2,974 SH   SOLE   2,974 0 0
CODEXIS INC COM 192005106 599 53,635 SH   SOLE   53,635 0 0
COGNEX CORP COM 192422103 6,927 164,066 SH   SOLE   148,911 0 15,155
CONSTRUCTION PARTNERS INC COM CL A 21044C107 61,271 3,627,622 SH   SOLE   3,584,484 0 43,138
COPART INC COM 217204106 6,867 100,212 SH   SOLE   91,382 0 8,830
COSTAR GROUP INC COM 22160N109 898 1,530 SH   SOLE   1,530 0 0
COSTCO WHSL CORP NEW COM 22160K105 657 2,305 SH   SOLE   1,770 0 535
CRYOPORT INC COM PAR $0.001 229050307 673 39,420 SH   SOLE   39,420 0 0
DANAHER CORPORATION COM 235851102 235 1,695 SH   SOLE   1,255 0 440
DESCARTES SYS GROUP INC COM 249906108 100,361 2,918,325 SH   SOLE   2,888,590 0 29,735
DIGI INTL INC COM 253798102 373 39,100 SH   SOLE   39,100 0 0
DOLBY LABORATORIES INC COM CL A 25659T107 326 6,018 SH   SOLE   5,518 0 500
DORMAN PRODUCTS INC COM 258278100 44,945 813,198 SH   SOLE   811,398 0 1,800
DOUGLAS DYNAMICS INC COM 25960R105 75,659 2,130,646 SH   SOLE   2,101,795 0 28,851
ECOLAB INC COM 278865100 205 1,315 SH   SOLE   735 0 580
ESCO TECHNOLOGIES INC COM 296315104 67,080 883,683 SH   SOLE   881,707 0 1,976
ESSENTIAL UTILS INC COM 29670G102 248 6,087 SH   SOLE   5,387 0 700
EVI INDUSTRIES INC COM 26929N102 14,180 898,630 SH   SOLE   881,640 0 16,990
EVOLENT HEALTH INC CL A 30050B101 349 64,340 SH   SOLE   64,340 0 0
EXPONENT INC COM 30214U102 122,602 1,704,937 SH   SOLE   1,686,957 0 17,980
EXXON MOBIL CORP COM 30231G102 708 18,654 SH   SOLE   18,504 0 150
FACTSET RESH SYS INC COM 303075105 514 1,971 SH   SOLE   1,971 0 0
FAIR ISAAC CORP COM 303250104 9,432 30,655 SH   SOLE   27,775 0 2,880
FASTENAL CO COM 311900104 848 27,127 SH   SOLE   23,027 0 4,100
FIRSTSERVICE CORP NEW COM 33767E202 59,420 770,487 SH   SOLE   760,039 0 10,448
FIVE9 INC COM 338307101 38,156 499,035 SH   SOLE   497,910 0 1,125
FORTINET INC COM 34959E109 580 5,733 SH   SOLE   5,733 0 0
FOX FACTORY HLDG CORP COM 35138V102 67,110 1,597,856 SH   SOLE   1,594,331 0 3,525
GARMIN LTD SHS H2906T109 343 4,570 SH   SOLE   3,870 0 700
GARTNER INC COM 366651107 4,945 49,663 SH   SOLE   44,938 0 4,725
GRACO INC COM 384109104 8,868 181,990 SH   SOLE   166,165 0 15,825
GRAND CANYON ED INC COM 38526M106 64,956 851,486 SH   SOLE   843,536 0 7,950
GUIDEWIRE SOFTWARE INC COM 40171V100 10,013 126,252 SH   SOLE   114,762 0 11,490
HEALTH CATALYST INC COM 42225T107 5,683 217,342 SH   SOLE   197,617 0 19,725
HEICO CORP NEW CL A 422806208 10,318 161,471 SH   SOLE   147,321 0 14,150
HELIOS TECHNOLOGIES INC COM 42328H109 56,274 1,484,014 SH   SOLE   1,480,799 0 3,215
HENRY JACK & ASSOC INC COM 426281101 13,964 89,951 SH   SOLE   81,751 0 8,200
HOME DEPOT INC COM 437076102 224 1,200 SH   SOLE   1,200 0 0
IAA INC COM 449253103 5,038 168,143 SH   SOLE   153,243 0 14,900
IDEXX LABS INC COM 45168D104 309 1,275 SH   SOLE   1,275 0 0
IHS MARKIT LTD SHS G47567105 1,179 19,650 SH   SOLE   17,212 0 2,438
INTEGRA LIFESCIENCES HLDGS C COM NEW 457985208 223 5,000 SH   SOLE   5,000 0 0
INTEL CORP COM 458140100 373 6,900 SH   SOLE   6,400 0 500
INTERNATIONAL BUSINESS MACHS COM 459200101 248 2,235 SH   SOLE   2,235 0 0
INTRICON CORP COM 46121H109 385 32,700 SH   SOLE   32,700 0 0
INTUIT COM 461202103 420 1,825 SH   SOLE   1,605 0 220
IPG PHOTONICS CORP COM 44980X109 289 2,625 SH   SOLE   2,625 0 0
ISHARES TR RUS 2000 GRW ETF 464287648 791 5,000 SH   SOLE   5,000 0 0
JOHN BEAN TECHNOLOGIES CORP COM 477839104 47,499 639,545 SH   SOLE   631,046 0 8,499
JOHNSON & JOHNSON COM 478160104 422 3,216 SH   SOLE   2,516 0 700
JPMORGAN CHASE & CO COM 46625H100 247 2,741 SH   SOLE   2,341 0 400
KIMBERLY CLARK CORP COM 494368103 543 4,250 SH   SOLE   4,250 0 0
LCI INDS COM 50189K103 4,522 67,658 SH   SOLE   60,953 0 6,705
LEMAITRE VASCULAR INC COM 525558201 42,889 1,721,081 SH   SOLE   1,717,231 0 3,850
LIGAND PHARMACEUTICALS INC COM NEW 53220K504 47,166 648,603 SH   SOLE   641,818 0 6,785
LINDE PLC SHS G5494J103 482 2,785 SH   SOLE   2,165 0 620
MARKEL CORP COM 570535104 764 824 SH   SOLE   674 0 150
MASTERCARD INC CL A 57636Q104 293 1,215 SH   SOLE   1,065 0 150
MERCK & CO. INC COM 58933Y105 512 6,650 SH   SOLE   6,650 0 0
MERCURY SYS INC COM 589378108 118,901 1,666,683 SH   SOLE   1,647,768 0 18,915
MERIT MED SYS INC COM 589889104 49,808 1,593,852 SH   SOLE   1,577,745 0 16,107
MESA LABS INC COM 59064R109 101,801 450,269 SH   SOLE   449,832 0 437
MGP INGREDIENTS INC NEW COM 55303J106 14,364 534,183 SH   SOLE   533,039 0 1,144
MICROSOFT CORP COM 594918104 733 4,649 SH   SOLE   4,039 0 610
NANOSTRING TECHNOLOGIES INC COM 63009R109 539 22,395 SH   SOLE   22,395 0 0
NATIONAL RESH CORP COM NEW 637372202 28,093 617,710 SH   SOLE   616,206 0 1,504
NEOGEN CORP COM 640491106 110,902 1,655,497 SH   SOLE   1,636,988 0 18,509
NIKE INC CL B 654106103 238 2,875 SH   SOLE   2,255 0 620
NOVANTA INC COM 67000B104 76,781 961,209 SH   SOLE   959,084 0 2,125
NV5 GLOBAL INC COM 62945V109 628 15,205 SH   SOLE   15,205 0 0
OMEGA FLEX INC COM 682095104 29,656 351,375 SH   SOLE   350,559 0 816
OMNICELL INC COM 68213N109 109,241 1,665,760 SH   SOLE   1,645,630 0 20,130
ORTHOPEDIATRICS CORP COM 68752L100 632 15,945 SH   SOLE   15,945 0 0
PALOMAR HLDGS INC COM 69753M105 416 7,150 SH   SOLE   7,150 0 0
PAYLOCITY HLDG CORP COM 70438V106 60,880 689,308 SH   SOLE   687,793 0 1,515
PFIZER INC COM 717081103 558 17,108 SH   SOLE   17,108 0 0
PLURALSIGHT INC COM CL A 72941B106 4,143 377,343 SH   SOLE   344,338 0 33,005
POOL CORPORATION COM 73278L105 12,812 65,113 SH   SOLE   59,063 0 6,050
PROCTER & GAMBLE CO COM 742718109 433 3,940 SH   SOLE   3,740 0 200
PROS HOLDINGS INC COM 74346Y103 58,216 1,876,128 SH   SOLE   1,872,003 0 4,125
PROTO LABS INC COM 743713109 43,432 570,501 SH   SOLE   569,276 0 1,225
RBC BEARINGS INC COM 75524B104 57,902 513,361 SH   SOLE   506,196 0 7,165
REALPAGE INC COM 75606N109 2,763 52,210 SH   SOLE   47,460 0 4,750
REPLIGEN CORP COM 759916109 129,638 1,342,839 SH   SOLE   1,328,164 0 14,675
ROGERS CORP COM 775133101 52,740 558,570 SH   SOLE   557,310 0 1,260
ROLLINS INC COM 775711104 14,240 394,018 SH   SOLE   360,111 0 33,907
ROPER TECHNOLOGIES INC COM 776696106 410 1,315 SH   SOLE   1,045 0 270
SHOTSPOTTER INC COM 82536T107 623 22,680 SH   SOLE   22,680 0 0
SIMPSON MANUFACTURING CO INC COM 829073105 83,917 1,353,935 SH   SOLE   1,342,519 0 11,416
SIMULATIONS PLUS INC COM 829214105 508 14,555 SH   SOLE   14,555 0 0
SITEONE LANDSCAPE SUPPLY INC COM 82982L103 78,870 1,071,318 SH   SOLE   1,057,883 0 13,435
SMUCKER J M CO COM NEW 832696405 456 4,105 SH   SOLE   3,325 0 780
SPS COMMERCE INC COM 78463M107 63,106 1,356,828 SH   SOLE   1,343,853 0 12,975
TELEFLEX INCORPORATED COM 879369106 9,799 33,459 SH   SOLE   30,484 0 2,975
TRACTOR SUPPLY CO COM 892356106 537 6,345 SH   SOLE   5,495 0 850
TREX CO INC COM 89531P105 84,447 1,053,745 SH   SOLE   1,042,120 0 11,625
TRIMBLE INC COM 896239100 396 12,429 SH   SOLE   12,429 0 0
TWIST BIOSCIENCE CORP COM 90184D100 625 20,425 SH   SOLE   20,425 0 0
TYLER TECHNOLOGIES INC COM 902252105 57,357 193,407 SH   SOLE   189,667 0 3,740
U S PHYSICAL THERAPY INC COM 90337L108 423 6,130 SH   SOLE   6,130 0 0
UNION PAC CORP COM 907818108 752 5,332 SH   SOLE   5,332 0 0
VAIL RESORTS INC COM 91879Q109 8,935 60,492 SH   SOLE   55,827 0 4,665
VEEVA SYS INC CL A COM 922475108 356 2,275 SH   SOLE   2,275 0 0
VERICEL CORP COM 92346J108 533 58,150 SH   SOLE   58,150 0 0
VERISK ANALYTICS INC COM 92345Y106 871 6,247 SH   SOLE   5,867 0 380
VERIZON COMMUNICATIONS INC COM 92343V104 203 3,773 SH   SOLE   3,773 0 0
VOCERA COMMUNICATIONS INC COM 92857F107 63,901 3,008,539 SH   SOLE   3,005,514 0 3,025
WASTE CONNECTIONS INC COM 94106B101 259 3,340 SH   SOLE   2,850 0 490
WATSCO INC COM 942622200 8,198 51,874 SH   SOLE   46,724 0 5,150
WD-40 CO COM 929236107 52,352 260,650 SH   SOLE   260,106 0 544
WEST PHARMACEUTICAL SVSC INC COM 955306105 12,427 81,625 SH   SOLE   74,655 0 6,970
WILLDAN GROUP INC COM 96924N100 561 26,255 SH   SOLE   26,255 0 0
WP CAREY INC COM 92936U109 282 4,850 SH   SOLE   3,850 0 1,000
XYLEM INC COM 98419M100 367 5,640 SH   SOLE   4,420 0 1,220