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 611 3,194 SH   SOLE 2,894 0 300
AAON INC COM PAR $0.004 000360206 52,702 1,490,874 SH   SOLE 1,458,999 0 31,875
ABBOTT LABS COM 002824100 410 9,223 SH   SOLE 9,223 0 0
ABBVIE INC COM 00287Y109 517 7,935 SH   SOLE 7,935 0 0
ACI WORLDWIDE INC COM 004498101 34,404 1,608,430 SH   SOLE 1,575,155 0 33,275
ACTUA CORP COM 005094107 201 14,300 SH   SOLE 13,700 0 600
ADOBE SYS INC COM 00724F101 203 1,560 SH   SOLE 1,110 0 450
ALIGN TECHNOLOGY INC COM 016255101 37,405 326,081 SH   SOLE 314,056 0 12,025
ALPHABET INC CAP STK CL C 02079K107 203 245 SH   SOLE 145 0 100
ALPHABET INC CAP STK CL A 02079K305 216 255 SH   SOLE 145 0 110
AMGEN INC COM 031162100 218 1,330 SH   SOLE 1,330 0 0
ANSYS INC COM 03662Q105 2,748 25,709 SH   SOLE 11,639 0 14,070
APPLE INC COM 037833100 421 2,930 SH   SOLE 1,580 0 1,350
BALCHEM CORP COM 057665200 26,712 324,099 SH   SOLE 314,524 0 9,575
BARD C R INC COM 067383109 505 2,031 SH   SOLE 1,591 0 440
BIO TECHNE CORP COM 09073M104 26,044 256,213 SH   SOLE 247,313 0 8,900
BLACKBAUD INC COM 09227Q100 56,344 734,887 SH   SOLE 716,387 0 18,500
BOTTOMLINE TECH DEL INC COM 101388106 34,218 1,446,869 SH   SOLE 1,418,074 0 28,795
BRIGHT HORIZONS FAM SOL IN D COM 109194100 2,016 27,805 SH   SOLE 11,305 0 16,500
CANTEL MEDICAL CORP COM 138098108 52,957 661,136 SH   SOLE 651,836 0 9,300
CHEVRON CORP NEW COM 166764100 352 3,274 SH   SOLE 3,274 0 0
COGNEX CORP COM 192422103 449 5,350 SH   SOLE 1,750 0 3,600
COPART INC COM 217204106 2,374 38,336 SH   SOLE 15,836 0 22,500
CORE LABORATORIES N V COM N22717107 1,361 11,778 SH   SOLE 5,328 0 6,450
COSTAR GROUP INC COM 22160N109 23,099 111,470 SH   SOLE 104,985 0 6,485
COSTCO WHSL CORP NEW COM 22160K105 423 2,525 SH   SOLE 1,810 0 715
DENTSPLY SIRONA INC COM 24906P109 237 3,795 SH   SOLE 3,795 0 0
DESCARTES SYS GROUP INC COM 249906108 36,568 1,596,840 SH   SOLE 1,592,490 0 4,350
DOLBY LABORATORIES INC COM 25659T107 333 6,363 SH   SOLE 5,863 0 500
DONALDSON INC COM 257651109 910 20,001 SH   SOLE 10,001 0 10,000
DORMAN PRODUCTS INC COM 258278100 38,259 465,835 SH   SOLE 459,435 0 6,400
DOW CHEM CO COM 260543103 261 4,100 SH   SOLE 4,100 0 0
DU PONT E I DE NEMOURS & CO COM 263534109 292 3,630 SH   SOLE 3,630 0 0
ESCO TECHNOLOGIES INC COM 296315104 8,651 148,894 SH   SOLE 148,519 0 375
EXA CORP COM 300614500 19,508 1,536,055 SH   SOLE 1,536,055 0 0
EXPONENT INC COM 30214U102 37,451 628,897 SH   SOLE 614,422 0 14,475
EXXON MOBIL CORP COM 30231G102 1,585 19,330 SH   SOLE 19,180 0 150
FACTSET RESH SYS INC COM 303075105 360 2,186 SH   SOLE 2,186 0 0
FASTENAL CO COM 311900104 733 14,229 SH   SOLE 11,469 0 2,760
FORTINET INC COM 34959E109 303 7,913 SH   SOLE 7,913 0 0
FOX FACTORY HLDG CORP COM 35138V102 42,587 1,483,861 SH   SOLE 1,479,811 0 4,050
GARMIN LTD SHS H2906T109 522 10,208 SH   SOLE 9,508 0 700
GENERAL ELECTRIC CO COM 369604103 237 7,954 SH   SOLE 7,954 0 0
GENTEX CORP COM 371901109 347 16,257 SH   SOLE 16,257 0 0
GRACO INC COM 384109104 2,094 22,248 SH   SOLE 9,823 0 12,425
GRAND CANYON ED INC COM 38526M106 44,665 623,720 SH   SOLE 621,945 0 1,775
GUIDEWIRE SOFTWARE INC COM 40171V100 1,330 23,610 SH   SOLE 11,035 0 12,575
HEALTHCARE SVCS GRP INC COM 421906108 39,218 910,153 SH   SOLE 895,053 0 15,100
HEALTHSTREAM INC COM 42222N103 35,093 1,448,317 SH   SOLE 1,420,622 0 27,695
HEICO CORP NEW CL A 422806208 2,306 30,749 SH   SOLE 12,899 0 17,850
HEXCEL CORP NEW COM 428291108 263 4,818 SH   SOLE 4,818 0 0
IDEXX LABS INC COM 45168D104 835 5,400 SH   SOLE 2,300 0 3,100
IHS MARKIT LTD SHS G47567105 2,311 55,080 SH   SOLE 27,707 0 27,373
INTEGRA LIFESCIENCES HLDGS C COM NEW 457985208 211 5,000 SH   SOLE 5,000 0 0
INTEL CORP COM 458140100 360 9,970 SH   SOLE 7,940 0 2,030
INTERNATIONAL BUSINESS MACHS COM 459200101 401 2,305 SH   SOLE 2,305 0 0
INTUIT COM 461202103 288 2,480 SH   SOLE 1,860 0 620
IPG PHOTONICS CORP COM 44980X109 1,554 12,875 SH   SOLE 6,675 0 6,200
JOHN BEAN TECHNOLOGIES CORP COM 477839104 21,182 240,846 SH   SOLE 235,621 0 5,225
JOHNSON & JOHNSON COM 478160104 485 3,891 SH   SOLE 2,931 0 960
JPMORGAN CHASE & CO COM 46625H100 293 3,341 SH   SOLE 2,941 0 400
KIMBERLY CLARK CORP COM 494368103 559 4,250 SH   SOLE 4,250 0 0
LEMAITRE VASCULAR INC COM 525558201 9,549 387,690 SH   SOLE 386,515 0 1,175
LIGAND PHARMACEUTICALS INC COM NEW 53220K504 38,184 360,774 SH   SOLE 352,724 0 8,050
MARKEL CORP COM 570535104 2,082 2,134 SH   SOLE 929 0 1,205
MASTERCARD INCORPORATED CL A 57636Q104 264 2,350 SH   SOLE 1,580 0 770
MATADOR RES CO COM 576485205 26,653 1,120,330 SH   SOLE 1,117,177 0 3,153
MEDIDATA SOLUTIONS INC COM 58471A105 35,423 614,031 SH   SOLE 599,806 0 14,225
MERCK & CO INC COM 58933Y105 508 8,000 SH   SOLE 8,000 0 0
MESA LABS INC COM 59064R109 46,069 375,463 SH   SOLE 375,463 0 0
MGP INGREDIENTS INC NEW COM 55303J106 37,358 688,874 SH   SOLE 686,874 0 2,000
MICROSOFT CORP COM 594918104 377 5,719 SH   SOLE 4,159 0 1,560
MOBILE MINI INC COM 60740F105 21,135 692,955 SH   SOLE 670,930 0 22,025
NATIONAL RESH CORP CL A 637372202 7,892 400,620 SH   SOLE 399,495 0 1,125
NATIONAL RESH CORP CL B 637372301 8,035 204,724 SH   SOLE 204,162 0 562
NEOGEN CORP COM 640491106 48,773 744,063 SH   SOLE 728,211 0 15,852
NIC INC COM 62914B100 33,128 1,640,018 SH   SOLE 1,610,653 0 29,365
NVE CORP COM NEW 629445206 19,735 238,377 SH   SOLE 237,727 0 650
OMNICELL INC COM 68213N109 61,539 1,513,866 SH   SOLE 1,478,291 0 35,575
PFIZER INC COM 717081103 603 17,635 SH   SOLE 17,635 0 0
PNC FINL SVCS GROUP INC COM 693475105 222 1,850 SH   SOLE 1,850 0 0
POLARIS INDS INC COM 731068102 1,353 16,146 SH   SOLE 8,146 0 8,000
POOL CORPORATION COM 73278L105 913 7,650 SH   SOLE 2,500 0 5,150
PRAXAIR INC COM 74005P104 343 2,895 SH   SOLE 2,115 0 780
PROCTER AND GAMBLE CO COM 742718109 354 3,940 SH   SOLE 3,740 0 200
PROS HOLDINGS INC COM 74346Y103 34,062 1,408,121 SH   SOLE 1,404,146 0 3,975
PROTO LABS INC COM 743713109 21,489 420,533 SH   SOLE 413,738 0 6,795
REPLIGEN CORP COM 759916109 42,797 1,215,810 SH   SOLE 1,187,660 0 28,150
ROGERS CORP COM 775133101 23,390 272,383 SH   SOLE 271,583 0 800
ROLLINS INC COM 775711104 35,467 955,215 SH   SOLE 918,578 0 36,637
SIMPSON MANUFACTURING CO INC COM 829073105 43,312 1,005,160 SH   SOLE 988,085 0 17,075
SITEONE LANDSCAPE SUPPLY INC COM 82982L103 38,362 792,434 SH   SOLE 776,309 0 16,125
SMITH A O COM 831865209 1,275 24,915 SH   SOLE 12,840 0 12,075
SMUCKER J M CO COM NEW 832696405 642 4,894 SH   SOLE 4,214 0 680
SOTHEBYS COM 835898107 30,708 675,193 SH   SOLE 673,318 0 1,875
SPS COMM INC COM 78463M107 39,651 677,911 SH   SOLE 663,336 0 14,575
STAMPS COM INC COM NEW 852857200 48,699 411,487 SH   SOLE 402,312 0 9,175
SUN HYDRAULICS CORP COM 866942105 29,032 803,976 SH   SOLE 801,726 0 2,250
TELEFLEX INC COM 879369106 1,463 7,550 SH   SOLE 2,600 0 4,950
TRACTOR SUPPLY CO COM 892356106 457 6,625 SH   SOLE 5,625 0 1,000
TREX CO INC COM 89531P105 33,857 487,926 SH   SOLE 476,751 0 11,175
TRIMBLE INC COM 896239100 401 12,514 SH   SOLE 12,514 0 0
TYLER TECHNOLOGIES INC COM 902252105 32,969 213,308 SH   SOLE 205,583 0 7,725
ULTIMATE SOFTWARE GROUP INC COM 90385D107 1,118 5,725 SH   SOLE 2,250 0 3,475
UNIFI INC COM NEW 904677200 1,179 41,533 SH   SOLE 40,133 0 1,400
UNION PAC CORP COM 907818108 600 5,665 SH   SOLE 5,665 0 0
VERISK ANALYTICS INC COM 92345Y106 580 7,147 SH   SOLE 6,467 0 680
VERIZON COMMUNICATIONS INC COM 92343V104 218 4,462 SH   SOLE 4,462 0 0
WABTEC CORP COM 929740108 2,000 25,638 SH   SOLE 10,998 0 14,640
WAGEWORKS INC COM 930427109 44,541 616,064 SH   SOLE 600,189 0 15,875
WD-40 CO COM 929236107 16,907 155,185 SH   SOLE 154,685 0 500
WEST PHARMACEUTICAL SVSC INC COM 955306105 908 11,125 SH   SOLE 5,125 0 6,000
WESTWOOD HLDGS GROUP INC COM 961765104 28,063 525,426 SH   SOLE 523,926 0 1,500