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

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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 54,758 1,167,040 SH   SOLE   846,267 0 320,773
3M Company COM 88579Y101 26,081 125,275 SH   SOLE   123,255 0 2,020
Acuity Brands, Inc. COM 00508Y102 68,660 337,759 SH   SOLE   265,624 0 72,135
Advisory Board Company COM 00762W107 319 6,190 SH   SOLE   4,340 0 1,850
Alarm.com Holdings, Inc. COM 011642105 50,898 1,352,602 SH   SOLE   978,075 0 374,527
Alphabet, Inc. Class A COM 02079K305 19,864 21,367 SH   SOLE   19,561 0 1,806
Alphabet, Inc. Class C COM 02079K107 16,944 18,646 SH   SOLE   18,126 0 520
Amazon.com, Inc. COM 023135106 49,837 51,485 SH   SOLE   48,857 0 2,628
Analog Devices, Inc. COM 032654105 24,054 309,180 SH   SOLE   296,752 0 12,428
Ansys, Inc. COM 03662Q105 71,063 584,018 SH   SOLE   432,291 0 151,727
Apple Inc. COM 037833100 5,990 41,592 SH   SOLE   32,442 0 9,150
athenahealth, Inc. COM 04685W103 145,306 1,033,842 SH   SOLE   802,863 0 230,979
Beacon Roofing Supply, Inc. COM 073685109 83,893 1,712,097 SH   SOLE   1,361,865 0 350,232
Berkshire Hathaway Inc. Class COM 084670702 279 1,645 SH   SOLE   1,070 0 575
Bio-Techne Corporation COM 09073M104 68,798 585,517 SH   SOLE   409,649 0 175,868
Burberry Group ADR COM 12082W204 2,839 131,603 SH   SOLE   128,687 0 2,916
Cabot Microelectronics Corpora COM 12709P103 21,324 288,820 SH   SOLE   225,845 0 62,975
Calavo Growers, Inc. COM 128246105 38,658 559,857 SH   SOLE   445,099 0 114,758
Cardinal Health, Inc. COM 14149y108 1,549 19,873 SH   SOLE   19,757 0 116
Cass Information Systems, Inc. COM 14808P109 28,820 439,055 SH   SOLE   349,825 0 89,230
Cerner Corporation COM 156782104 21,652 325,741 SH   SOLE   310,475 0 15,266
ChannelAdvisor Corporation COM 159179100 18,667 1,616,232 SH   SOLE   1,129,149 0 487,083
Cheesecake Factory, Inc. COM 163072101 25,418 505,320 SH   SOLE   398,874 0 106,446
Chemed Corporation COM 16359R103 137,299 671,291 SH   SOLE   515,433 0 155,858
Cisco Systems, Inc. COM 17275R102 20,261 647,308 SH   SOLE   640,724 0 6,584
Cno Financial COM 12621E103 482 23,094 SH   SOLE   23,094 0 0
Coca Cola Co Com COM 191216100 260 5,786 SH   SOLE   4,704 0 1,082
Cognex Corporation COM 192422103 21,247 250,263 SH   SOLE   147,900 0 102,363
Colgate-Palmolive Company COM 194162103 2,815 37,976 SH   SOLE   37,772 0 204
CoStar Group, Inc. COM 22160N109 156,974 595,500 SH   SOLE   449,776 0 145,724
Cree, Inc. COM 225447101 1,062 43,077 SH   SOLE   21,032 0 22,045
Digi International, Inc. COM 253798102 15,327 1,510,048 SH   SOLE   1,196,142 0 313,906
Diplomat Pharmacy, Inc. COM 25456K101 20,912 1,412,945 SH   SOLE   972,241 0 440,704
Dorman Products, Inc. COM 258278100 65,537 791,795 SH   SOLE   552,387 0 239,408
Ecolab, Inc. COM 278865100 52,411 394,811 SH   SOLE   376,195 0 18,616
Ellie Mae, Inc. COM 28849P100 79,258 721,119 SH   SOLE   519,643 0 201,476
Evolent Health, Inc. Class A COM 30050B101 58,878 2,322,594 SH   SOLE   1,809,811 0 512,783
ExlService Holdings, Inc. COM 302081104 55,009 989,732 SH   SOLE   694,253 0 295,479
Exponent, Inc. COM 30214u102 28,935 496,308 SH   SOLE   387,701 0 108,607
Fastenal Company COM 311900104 81,908 1,881,636 SH   SOLE   1,452,630 0 429,006
Financial Engines, Inc. COM 317485100 51,226 1,399,615 SH   SOLE   1,006,223 0 393,392
Fiserv, Inc. COM 337738108 62,447 510,442 SH   SOLE   487,037 0 23,405
Five Below, Inc. COM 33829M101 109,517 2,218,288 SH   SOLE   1,693,635 0 524,653
Freshpet, Inc. COM 358039105 34,301 2,066,316 SH   SOLE   1,617,526 0 448,790
General Electric Company COM 369604103 2,316 85,755 SH   SOLE   83,312 0 2,443
Gentex Corporation COM 371901109 88,800 4,681,052 SH   SOLE   3,767,958 0 913,094
Globant S.A. COM L44385109 43,179 994,002 SH   SOLE   762,449 0 231,553
Grand Canyon Education, Inc. COM 38526M106 194,395 2,479,209 SH   SOLE   1,931,376 0 547,833
Healthcare Services Group, Inc COM 421906108 138,700 2,961,768 SH   SOLE   2,277,047 0 684,721
Healthstream, Inc. COM 42222N103 54,691 2,077,924 SH   SOLE   1,488,300 0 589,624
HEICO Corporation COM 422806109 116,486 1,621,457 SH   SOLE   1,221,735 0 399,722
Henry Schein, Inc. COM 806407102 24,980 136,489 SH   SOLE   88,083 0 48,406
Heska Corporation COM 42805e306 23,907 234,217 SH   SOLE   182,839 0 51,378
Hormel Foods Corp. COM 440452100 335 9,808 SH   SOLE   9,808 0 0
IHS Markit Ltd. COM G47567105 73,436 1,667,493 SH   SOLE   1,297,431 0 370,062
Illinois Tool Works Inc. COM 452308109 2,795 19,513 SH   SOLE   19,337 0 176
InnerWorkings, Inc. COM 45773Y105 38,027 3,278,231 SH   SOLE   2,212,830 0 1,065,401
Inovalon Holdings, Inc. Class COM 45781D101 41,322 3,142,392 SH   SOLE   2,446,610 0 695,782
Intel Corporation COM 458140100 2,483 73,588 SH   SOLE   69,561 0 4,027
International Flavors & Fragra COM 459506101 44,488 329,543 SH   SOLE   256,362 0 73,181
Ishares Core S&P 500 Etf COM 464287200 1,098 4,510 SH   SOLE   4,510 0 0
Ishares Core US Growth ETF COM 464287671 273 5,657 SH   SOLE   1,263 0 4,394
iShares Russell Midcap ETF COM 464287499 269 1,398 SH   SOLE   1,398 0 0
Ishares Tr Russell 1000 COM 464287622 536 3,961 SH   SOLE   3,961 0 0
Ishares Tr Russell 1000 Growth COM 464287614 561 4,713 SH   SOLE   4,713 0 0
Ishares Tr Russell 2000 COM 464287655 859 6,097 SH   SOLE   6,097 0 0
Ishares Tr Russell 2000 Growth COM 464287648 299 1,769 SH   SOLE   228 0 1,541
Johnson & Johnson COM 478160104 3,785 28,615 SH   SOLE   27,800 0 815
JPMorgan Chase & Co. COM 46625H100 967 10,575 SH   SOLE   9,465 0 1,110
Knight Transportation, Inc. COM 499064103 33,800 912,292 SH   SOLE   714,044 0 198,248
LKQ Corporation COM 501889208 52,779 1,601,794 SH   SOLE   1,185,364 0 416,430
MAXIMUS, Inc. COM 577933104 72,228 1,153,253 SH   SOLE   821,781 0 331,472
Mednax, Inc. COM 58502B106 53,887 892,612 SH   SOLE   701,274 0 191,338
Medtronic plc COM G5960L103 21,678 244,259 SH   SOLE   86,534 0 157,725
Microsoft Corporation COM 594918104 63,593 922,574 SH   SOLE   882,432 0 40,142
Middleby Corporation COM 596278101 29,497 242,754 SH   SOLE   141,274 0 101,480
Mobile Mini, Inc. COM 60740F105 25,845 865,813 SH   SOLE   690,366 0 175,447
National Instruments Corporati COM 636518102 223,868 5,566,077 SH   SOLE   4,367,285 0 1,198,792
Neogen Corporation COM 640491106 58,253 842,899 SH   SOLE   652,711 0 190,188
Novadaq Technologies, Inc. COM 66987G102 37,089 3,164,568 SH   SOLE   2,240,024 0 924,544
Oracle Corporation COM 68389X105 251 5,000 SH   SOLE   5,000 0 0
Paccar Inc. COM 693718108 379 5,743 SH   SOLE   5,743 0 0
Patterson Companies, Inc. COM 703395103 19,512 415,591 SH   SOLE   324,161 0 91,430
Paychex, Inc. COM 704326107 2,258 39,654 SH   SOLE   39,429 0 225
Paylocity Holding Corp. COM 70438v106 36,905 816,851 SH   SOLE   639,190 0 177,661
Pegasystems, Inc. COM 705573103 70,760 1,212,680 SH   SOLE   949,112 0 263,568
PepsiCo, Inc. COM 713448108 3,206 27,758 SH   SOLE   27,622 0 136
Power Integrations, Inc. COM 739276103 39,941 547,894 SH   SOLE   419,687 0 128,207
PRA Group, Inc. COM 69354N106 113,481 2,994,231 SH   SOLE   2,295,884 0 698,347
Praxair, Inc. COM 74005P104 24,019 181,209 SH   SOLE   174,307 0 6,902
Procter & Gamble Company COM 742718109 2,063 23,677 SH   SOLE   23,541 0 136
Pros Holdings, Inc. COM 74346Y103 59,402 2,168,749 SH   SOLE   1,514,048 0 654,701
Proto Labs, Inc. COM 743713109 132,339 1,967,865 SH   SOLE   1,550,857 0 417,008
Qualcomm, Inc. COM 747525103 764 13,828 SH   SOLE   12,574 0 1,254
Reckitt Benckiser Group ADR COM 756255204 21,492 1,062,791 SH   SOLE   1,049,489 0 13,302
Ritchie Bros. Auctioneers, Inc COM 767744105 104,618 3,640,160 SH   SOLE   2,852,781 0 787,379
Roche Holding Ltd. ADR COM 771195104 27,599 865,858 SH   SOLE   827,265 0 38,593
Rollins, Inc. COM 775711104 72,495 1,780,762 SH   SOLE   1,431,831 0 348,931
Roper Technologies, Inc. COM 776696106 286 1,234 SH   SOLE   1,234 0 0
Rydex ETF Trust Gug S&p500 Pu COM 78355W403 659 6,996 SH   SOLE   6,996 0 0
Salesforce.com, Inc. COM 79466L302 33,880 391,219 SH   SOLE   370,673 0 20,546
Schlumberger NV COM 806857108 2,596 39,429 SH   SOLE   39,199 0 230
Snap-on, Inc. COM 833034101 34,248 216,758 SH   SOLE   172,801 0 43,957
Spdr S&P 500 Etf COM 78462F103 2,400 9,926 SH   SOLE   9,926 0 0
SPS Commerce, Inc. COM 78463M107 48,795 765,290 SH   SOLE   599,297 0 165,993
Starbucks Corporation COM 855244109 49,731 852,879 SH   SOLE   810,970 0 41,909
Stericycle, Inc. COM 858912108 992 13,004 SH   SOLE   13,004 0 0
Stratasys Ltd. COM M85548101 33,947 1,456,339 SH   SOLE   1,133,039 0 323,300
Stryker Corp Com COM 863667101 264 1,900 SH   SOLE   1,900 0 0
Target Corporation COM 87612E106 1,314 25,134 SH   SOLE   24,832 0 302
Teladoc, Inc. COM 87918A105 23,392 674,125 SH   SOLE   529,129 0 144,996
Tile Shop Holdings, Inc. COM 88677Q109 30,518 1,477,869 SH   SOLE   1,156,836 0 321,033
Tyler Technologies, Inc. COM 902252105 19,154 109,034 SH   SOLE   79,333 0 29,701
U.S. Bancorp COM 902973304 2,241 43,170 SH   SOLE   43,170 0 0
U.S. Physical Therapy, Inc. COM 90337L108 23,840 394,694 SH   SOLE   313,317 0 81,377
Ultimate Software Group, Inc. COM 90385D107 152,745 727,149 SH   SOLE   544,853 0 182,296
United Natural Foods, Inc. COM 911163103 78,143 2,129,232 SH   SOLE   1,643,485 0 485,747
UnitedHealth Group, Inc. COM 91324P102 40,298 217,333 SH   SOLE   204,831 0 12,502
Veeva Systems, Inc. Class A COM 922475108 99,524 1,623,293 SH   SOLE   1,208,665 0 414,628
Verint Systems, Inc. COM 92343X100 64,553 1,586,078 SH   SOLE   1,178,155 0 407,923
Verisk Analytics, Inc. COM 92345Y106 80,671 956,153 SH   SOLE   723,361 0 232,792
WABCO Holdings, Inc. COM 92927K102 22,774 178,606 SH   SOLE   105,847 0 72,759
WageWorks, Inc. COM 930427109 46,638 694,024 SH   SOLE   491,370 0 202,654
Wal-Mart Stores, Inc. COM 931142103 2,220 29,332 SH   SOLE   29,174 0 158
Walgreens Boots Alliance, Inc. COM 931427108 40,545 517,747 SH   SOLE   498,891 0 18,856
Watsco, Inc. COM 942622200 14,930 96,823 SH   SOLE   64,830 0 31,993
Wells Fargo & Company COM 949746101 381 6,881 SH   SOLE   4,190 0 2,691
West Pharmaceutical Services, COM 955306105 48,340 511,423 SH   SOLE   395,842 0 115,581
Whole Foods Market, Inc. COM 966837106 562 13,353 SH   SOLE   12,078 0 1,275
Alger Fds Ii Alger Spctra I COM 015566300 348 17,775 SH   SOLE   17,775 0 0
Dodge & Cox Stk Fd Com COM 256219106 539 2,798 SH   SOLE   1,188 0 1,611
Fidelity Concord Str T Sp 500 COM 315911701 1,954 22,947 SH   SOLE   10,259 0 12,687
Growth Fd Amer Inc Com COM 399874106 738 15,635 SH   SOLE   15,635 0 0
JPMORGAN TR II LARGE CAP GR A COM 4812C0506 217 5,680 SH   SOLE   5,680 0 0
RB All Cap Growth Fund Investo COM 46141P305 203 12,495 SH   SOLE   12,495 0 0
Riverbridge Growth Fund - Inst COM 46141P404 6,523 396,541 SH   SOLE   396,541 0 0
Third Ave Tr Real Estate Fd COM 884116401 231 7,009 SH   SOLE   7,009 0 0
Vanguard Index Tr 500 Index Ad COM 922908710 6,437 28,769 SH   SOLE   0 0 28,769
Vanguard Index Trust 500 Index COM 922908108 6,611 29,549 SH   SOLE   19,814 0 9,734