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
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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
2U, Inc. COM 90214J101 59,684 1,065,022 SH   SOLE   736,135 0 328,887
3M Company COM 88579Y101 26,114 124,411 SH   SOLE   122,658 0 1,753
Acuity Brands, Inc. COM 00508Y102 58,716 342,809 SH   SOLE   267,812 0 74,997
Advisory Board Company COM 00762W107 215 4,009 SH   SOLE   3,964 0 45
Agco Corp Com COM 001084102 255 3,457 SH   SOLE   3,457 0 0
Alarm.com Holdings, Inc. COM 011642105 56,248 1,244,983 SH   SOLE   859,034 0 385,949
Alphabet, Inc. Class A COM 02079K305 20,741 21,301 SH   SOLE   19,460 0 1,841
Alphabet, Inc. Class C COM 02079K107 17,804 18,563 SH   SOLE   18,046 0 517
Amazon.com, Inc. COM 023135106 49,110 51,084 SH   SOLE   48,439 0 2,645
Analog Devices, Inc. COM 032654105 28,963 336,112 SH   SOLE   322,357 0 13,755
Ansys, Inc. COM 03662Q105 72,445 590,278 SH   SOLE   430,968 0 159,310
Apple Inc. COM 037833100 6,410 41,592 SH   SOLE   32,442 0 9,150
AT&T Inc. COM 00206R102 218 5,556 SH   SOLE   4,400 0 1,156
athenahealth, Inc. COM 04685W103 122,089 981,741 SH   SOLE   744,151 0 237,590
Baidu, Inc. Sponsored ADR Clas COM 056752108 272 1,100 SH   SOLE   100 0 1,000
Beacon Roofing Supply, Inc. COM 073685109 83,274 1,624,850 SH   SOLE   1,265,524 0 359,326
Berkshire Hathaway Inc. Class COM 084670702 302 1,645 SH   SOLE   1,070 0 575
Bio-Techne Corporation COM 09073M104 65,942 545,471 SH   SOLE   364,434 0 181,037
Boeing Co Com COM 097023105 216 849 SH   SOLE   749 0 100
Burberry Group ADR COM 12082W204 273 11,390 SH   SOLE   11,390 0 0
Cabot Microelectronics Corpora COM 12709P103 20,014 250,394 SH   SOLE   187,541 0 62,853
Calavo Growers, Inc. COM 128246105 33,602 459,043 SH   SOLE   345,069 0 113,974
Cardinal Health, Inc. COM 14149y108 1,318 19,699 SH   SOLE   19,699 0 0
Cass Information Systems, Inc. COM 14808P109 22,586 356,023 SH   SOLE   267,908 0 88,115
Cerner Corporation COM 156782104 23,152 324,616 SH   SOLE   309,393 0 15,223
ChannelAdvisor Corporation COM 159179100 17,413 1,514,202 SH   SOLE   1,013,979 0 500,223
Cheesecake Factory, Inc. COM 163072101 18,508 439,414 SH   SOLE   333,497 0 105,917
Chemed Corporation COM 16359R103 114,249 565,450 SH   SOLE   420,225 0 145,225
Cisco Systems, Inc. COM 17275R102 21,609 642,546 SH   SOLE   636,876 0 5,670
Coca-Cola Company COM 191216100 260 5,787 SH   SOLE   4,704 0 1,083
Cognex Corporation COM 192422103 28,353 257,098 SH   SOLE   149,143 0 107,955
Colgate-Palmolive Company COM 194162103 2,748 37,722 SH   SOLE   37,722 0 0
CoStar Group, Inc. COM 22160N109 153,667 572,852 SH   SOLE   422,446 0 150,406
Cree, Inc. COM 225447101 1,332 47,261 SH   SOLE   24,659 0 22,602
Digi International, Inc. COM 253798102 13,871 1,308,613 SH   SOLE   994,941 0 313,672
Diplomat Pharmacy, Inc. COM 25456K101 27,643 1,334,784 SH   SOLE   878,574 0 456,210
Dorman Products, Inc. COM 258278100 52,876 738,279 SH   SOLE   491,998 0 246,281
Ecolab, Inc. COM 278865100 50,504 392,691 SH   SOLE   374,212 0 18,479
Ellie Mae, Inc. COM 28849P100 54,184 659,738 SH   SOLE   453,623 0 206,115
Evolent Health, Inc. Class A COM 30050B101 38,426 2,158,788 SH   SOLE   1,644,076 0 514,712
ExlService Holdings, Inc. COM 302081104 53,849 923,340 SH   SOLE   618,733 0 304,607
Exponent, Inc. COM 30214u102 32,323 437,387 SH   SOLE   328,633 0 108,754
Fastenal Company COM 311900104 88,035 1,931,436 SH   SOLE   1,484,118 0 447,318
Financial Engines, Inc. COM 317485100 44,489 1,280,272 SH   SOLE   881,335 0 398,937
Fiserv, Inc. COM 337738108 65,323 506,540 SH   SOLE   483,411 0 23,129
Five Below, Inc. COM 33829M101 114,811 2,092,038 SH   SOLE   1,552,280 0 539,758
Freshpet, Inc. COM 358039105 27,896 1,782,504 SH   SOLE   1,334,614 0 447,890
General Electric Company COM 369604103 289 11,939 SH   SOLE   9,956 0 1,983
General Mls Inc Com COM 370334104 224 4,324 SH   SOLE   4,324 0 0
Gentex Corporation COM 371901109 104,407 5,273,063 SH   SOLE   3,980,867 0 1,292,196
Globant S.A. COM L44385109 65,117 1,625,091 SH   SOLE   1,235,492 0 389,599
Grand Canyon Education, Inc. COM 38526M106 212,254 2,337,088 SH   SOLE   1,775,323 0 561,765
Healthcare Services Group, Inc COM 421906108 151,317 2,803,728 SH   SOLE   2,100,039 0 703,689
Healthstream, Inc. COM 42222N103 44,680 1,911,845 SH   SOLE   1,309,973 0 601,872
HEICO Corporation COM 422806109 138,429 1,541,357 SH   SOLE   1,129,154 0 412,203
Henry Schein, Inc. COM 806407102 37,579 458,340 SH   SOLE   345,996 0 112,344
Heska Corporation COM 42805e306 18,047 204,874 SH   SOLE   153,401 0 51,473
IHS Markit Ltd. COM G47567105 74,238 1,684,163 SH   SOLE   1,296,695 0 387,468
Illinois Tool Works Inc. COM 452308109 2,792 18,870 SH   SOLE   18,870 0 0
InnerWorkings, Inc. COM 45773Y105 35,181 3,127,213 SH   SOLE   2,023,712 0 1,103,501
Inovalon Holdings, Inc. Class COM 45781D101 51,183 3,001,920 SH   SOLE   2,284,178 0 717,742
Intel Corporation COM 458140100 2,791 73,281 SH   SOLE   69,625 0 3,656
International Flavors & Fragra COM 459506101 48,504 339,399 SH   SOLE   262,600 0 76,799
Ishares Core S&P 500 Etf COM 464287200 6,816 26,949 SH   SOLE   26,949 0 0
iShares Russell Midcap ETF COM 464287499 276 1,398 SH   SOLE   1,398 0 0
Ishares Tr Russell 1000 COM 464287622 553 3,954 SH   SOLE   3,954 0 0
Ishares Tr Russell 1000 Growth COM 464287614 589 4,713 SH   SOLE   4,713 0 0
Ishares Tr Russell 2000 COM 464287655 907 6,124 SH   SOLE   6,124 0 0
Ishares Tr Russell 2000 Growth COM 464287648 322 1,802 SH   SOLE   228 0 1,574
Johnson & Johnson COM 478160104 3,688 28,368 SH   SOLE   27,693 0 675
JPMorgan Chase & Co. COM 46625H100 1,010 10,575 SH   SOLE   9,465 0 1,110
Knight-Swift Transportation Ho COM 499049104 32,919 792,280 SH   SOLE   594,230 0 198,050
LKQ Corporation COM 501889208 58,255 1,618,654 SH   SOLE   1,180,481 0 438,173
MAXIMUS, Inc. COM 577933104 68,465 1,061,467 SH   SOLE   721,385 0 340,082
Mednax, Inc. COM 58502B106 38,203 885,978 SH   SOLE   688,225 0 197,753
Medtronic plc COM G5960L103 18,987 244,142 SH   SOLE   88,539 0 155,603
Microsoft Corporation COM 594918104 68,128 914,586 SH   SOLE   875,095 0 39,491
Middleby Corporation COM 596278101 31,784 247,985 SH   SOLE   141,522 0 106,463
Mobile Mini, Inc. COM 60740F105 45,823 1,330,145 SH   SOLE   1,009,442 0 320,703
National Instruments Corporati COM 636518102 147,544 3,498,799 SH   SOLE   2,698,005 0 800,794
Neogen Corporation COM 640491106 61,259 790,851 SH   SOLE   596,254 0 194,597
Oracle Corporation COM 68389X105 242 5,000 SH   SOLE   5,000 0 0
Paccar Inc. COM 693718108 415 5,743 SH   SOLE   5,743 0 0
Patterson Companies, Inc. COM 703395103 798 20,646 SH   SOLE   20,646 0 0
Paychex, Inc. COM 704326107 2,374 39,597 SH   SOLE   39,597 0 0
Paylocity Holding Corp. COM 70438v106 34,469 706,052 SH   SOLE   528,760 0 177,292
Pegasystems, Inc. COM 705573103 60,255 1,045,191 SH   SOLE   783,057 0 262,134
PepsiCo, Inc. COM 713448108 3,063 27,489 SH   SOLE   27,489 0 0
Power Integrations, Inc. COM 739276103 34,932 477,216 SH   SOLE   349,134 0 128,082
PRA Group, Inc. COM 69354N106 80,273 2,801,854 SH   SOLE   2,091,692 0 710,162
Praxair, Inc. COM 74005P104 25,156 180,022 SH   SOLE   173,269 0 6,753
Procter & Gamble Company COM 742718109 2,414 26,534 SH   SOLE   26,534 0 0
Pros Holdings, Inc. COM 74346Y103 62,889 2,606,271 SH   SOLE   1,746,047 0 860,224
Proto Labs, Inc. COM 743713109 148,629 1,850,924 SH   SOLE   1,423,840 0 427,084
Reckitt Benckiser Group ADR COM 756255204 19,418 1,062,165 SH   SOLE   1,051,006 0 11,159
Ritchie Bros. Auctioneers, Inc COM 767744105 108,642 3,435,861 SH   SOLE   2,629,968 0 805,893
Roche Holding Ltd. ADR COM 771195104 27,337 856,021 SH   SOLE   817,263 0 38,758
Rollins, Inc. COM 775711104 82,631 1,790,872 SH   SOLE   1,425,547 0 365,325
Rydex ETF Trust Gug S&p500 Pu COM 78355W403 700 6,996 SH   SOLE   6,996 0 0
Salesforce.com, Inc. COM 79466L302 36,364 389,248 SH   SOLE   368,753 0 20,495
Schlumberger NV COM 806857108 2,731 39,153 SH   SOLE   39,153 0 0
Snap-on, Inc. COM 833034101 33,521 224,957 SH   SOLE   178,318 0 46,639
Spdr S&P 500 Etf COM 78462F103 2,494 9,926 SH   SOLE   9,926 0 0
SPS Commerce, Inc. COM 78463M107 37,461 660,580 SH   SOLE   494,813 0 165,767
Starbucks Corporation COM 855244109 47,953 892,814 SH   SOLE   851,495 0 41,319
Stericycle, Inc. COM 858912108 294 4,108 SH   SOLE   4,108 0 0
Stratasys Ltd. COM M85548101 20,143 871,258 SH   SOLE   652,797 0 218,461
Stryker Corp Com COM 863667101 270 1,900 SH   SOLE   1,900 0 0
Target Corporation COM 87612E106 1,057 17,911 SH   SOLE   17,795 0 116
Teladoc, Inc. COM 87918A105 19,759 596,059 SH   SOLE   451,035 0 145,024
Tile Shop Holdings, Inc. COM 88677Q109 16,184 1,274,330 SH   SOLE   954,921 0 319,409
Tyler Technologies, Inc. COM 902252105 44,160 253,326 SH   SOLE   192,617 0 60,709
U.S. Bancorp COM 902973304 2,340 43,670 SH   SOLE   43,670 0 0
U.S. Physical Therapy, Inc. COM 90337L108 21,211 345,182 SH   SOLE   262,265 0 82,917
Ultimate Software Group, Inc. COM 90385D107 132,359 698,099 SH   SOLE   509,590 0 188,509
United Natural Foods, Inc. COM 911163103 82,404 1,981,330 SH   SOLE   1,485,333 0 495,997
UnitedHealth Group, Inc. COM 91324P102 42,211 215,528 SH   SOLE   203,152 0 12,376
VANGUARD INDEX FDS EXTEND MKT COM 922908652 2,386 22,272 SH   SOLE   0 0 22,272
Veeva Systems, Inc. Class A COM 922475108 88,390 1,566,914 SH   SOLE   1,136,823 0 430,091
Verint Systems, Inc. COM 92343X100 62,580 1,495,351 SH   SOLE   1,074,509 0 420,842
Verisk Analytics, Inc. COM 92345Y106 80,440 966,938 SH   SOLE   722,175 0 244,763
Visa, Inc. COM 92826C839 22,924 217,827 SH   SOLE   206,833 0 10,994
WABCO Holdings, Inc. COM 92927K102 27,118 183,229 SH   SOLE   106,296 0 76,933
WageWorks, Inc. COM 930427109 47,838 788,112 SH   SOLE   541,980 0 246,132
Wal-Mart Stores, Inc. COM 931142103 2,273 29,084 SH   SOLE   29,084 0 0
Walgreens Boots Alliance, Inc. COM 931427108 39,301 508,945 SH   SOLE   490,378 0 18,567
Watsco, Inc. COM 942622200 26,265 163,063 SH   SOLE   102,097 0 60,966
Wells Fargo & Company COM 949746101 379 6,881 SH   SOLE   4,190 0 2,691
West Pharmaceutical Services, COM 955306105 50,229 521,804 SH   SOLE   396,692 0 125,112
Alger Fds Ii Alger Spctra I COM 015566300 367 17,775 SH   SOLE   17,775 0 0
Dodge & Cox Stk Fd Com COM 256219106 561 2,798 SH   SOLE   1,188 0 1,611
Fidelity Concord Str T Sp 500 COM 315911701 1,905 21,518 SH   SOLE   14,746 0 6,772
Growth Fd Amer Inc Com COM 399874106 515 10,380 SH   SOLE   10,380 0 0
JPMORGAN TR II LARGE CAP GR A COM 4812C0506 229 5,680 SH   SOLE   5,680 0 0
RB All Cap Growth Fund Investo COM 46141P305 248 14,980 SH   SOLE   14,980 0 0
Riverbridge Growth Fund - Inst COM 46141P404 6,992 417,444 SH   SOLE   417,444 0 0
Third Ave Tr Real Estate Fd COM 884116401 240 7,009 SH   SOLE   7,009 0 0
Vanguard Index Tr 500 Index Ad COM 922908710 6,691 28,769 SH   SOLE   0 0 28,769
Vanguard Index Trust 500 Index COM 922908108 6,846 29,435 SH   SOLE   20,506 0 8,929