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 37,765 1,252,578 SH   SOLE   908,494 0 344,084
3M Company COM 88579Y101 22,959 128,572 SH   SOLE   126,340 0 2,232
Acuity Brands, Inc. COM 00508Y102 52,788 228,660 SH   SOLE   176,036 0 52,624
Advisory Board Company COM 00762W107 61,303 1,843,696 SH   SOLE   1,416,771 0 426,925
Alphabet, Inc. Class A COM 02079K305 17,387 21,941 SH   SOLE   19,810 0 2,131
Alphabet, Inc. Class C COM 02079K107 14,603 18,920 SH   SOLE   18,386 0 534
Amazon.com, Inc. COM 023135106 38,967 51,965 SH   SOLE   48,785 0 3,180
Ansys, Inc. COM 03662Q105 56,045 605,955 SH   SOLE   453,071 0 152,884
Apple Inc. COM 037833100 4,842 41,807 SH   SOLE   32,657 0 9,150
athenahealth, Inc. COM 04685W103 108,974 1,036,171 SH   SOLE   797,849 0 238,322
Beacon Roofing Supply, Inc. COM 073685109 83,534 1,813,208 SH   SOLE   1,430,326 0 382,882
Bio-Techne Corporation COM 09073M104 65,213 634,184 SH   SOLE   445,749 0 188,435
Brooklyn Bancorp Inc. COM 113809107 268 1,645 SH   SOLE   1,070 0 575
Burberry Group ADR COM 12082W204 11,107 600,464 SH   SOLE   591,614 0 8,850
Cabot Microelectronics Corpora COM 12709P103 20,161 319,149 SH   SOLE   243,225 0 75,924
Calavo Growers, Inc. COM 128246105 22,325 363,601 SH   SOLE   285,121 0 78,480
Cardinal Health, Inc. COM 14149y108 1,367 18,996 SH   SOLE   18,766 0 230
Cass Information Systems, Inc. COM 14808P109 35,413 481,351 SH   SOLE   375,375 0 105,976
Cerner Corporation COM 156782104 13,075 276,022 SH   SOLE   260,231 0 15,791
ChannelAdvisor Corporation COM 159179100 24,741 1,724,089 SH   SOLE   1,201,187 0 522,902
Cheesecake Factory, Inc. COM 163072101 33,245 555,196 SH   SOLE   428,625 0 126,571
Chemed Corporation COM 16359R103 122,561 764,047 SH   SOLE   582,551 0 181,496
Cisco Systems, Inc. COM 17275R102 19,863 657,271 SH   SOLE   649,621 0 7,650
Coca Cola Co Com COM 191216100 240 5,786 SH   SOLE   4,704 0 1,082
Cognex Corporation COM 192422103 63,524 998,493 SH   SOLE   700,855 0 297,638
Colgate-Palmolive Company COM 194162103 2,608 39,851 SH   SOLE   39,446 0 405
CoStar Group, Inc. COM 22160N109 130,613 692,942 SH   SOLE   524,037 0 168,905
Cree, Inc. COM 225447101 1,374 52,052 SH   SOLE   24,696 0 27,356
Digi International, Inc. COM 253798102 22,602 1,643,802 SH   SOLE   1,272,004 0 371,798
Diplomat Pharmacy, Inc. COM 25456K101 18,666 1,481,428 SH   SOLE   1,038,584 0 442,844
Dorman Products, Inc. COM 258278100 62,708 858,307 SH   SOLE   597,683 0 260,624
Ecolab, Inc. COM 278865100 46,988 400,854 SH   SOLE   378,340 0 22,514
Ellie Mae, Inc. COM 28849P100 65,308 780,446 SH   SOLE   559,903 0 220,543
ExlService Holdings, Inc. COM 302081104 53,620 1,063,045 SH   SOLE   749,031 0 314,014
Exponent, Inc. COM 30214u102 32,836 544,546 SH   SOLE   415,180 0 129,366
Exxon Mobil Corporation COM 30231G102 248 2,744 SH   SOLE   2,131 0 613
Fastenal Company COM 311900104 91,513 1,947,914 SH   SOLE   1,514,069 0 433,845
FedEx Corporation COM 31428X106 235 1,262 SH   SOLE   1,262 0 0
Financial Engines, Inc. COM 317485100 55,468 1,509,342 SH   SOLE   1,085,767 0 423,575
Fiserv, Inc. COM 337738108 55,700 524,084 SH   SOLE   495,832 0 28,252
Five Below, Inc. COM 33829M101 94,209 2,357,588 SH   SOLE   1,795,557 0 562,031
Freshpet, Inc. COM 358039105 23,157 2,281,518 SH   SOLE   1,748,057 0 533,461
General Electric Company COM 369604103 2,830 89,555 SH   SOLE   86,854 0 2,701
General Mls Inc Com COM 370334104 215 3,484 SH   SOLE   3,484 0 0
Gentex Corporation COM 371901109 130,762 6,641,055 SH   SOLE   5,106,448 0 1,534,607
Grand Canyon Education, Inc. COM 38526M106 167,138 2,859,508 SH   SOLE   2,213,158 0 646,350
Healthcare Services Group, Inc COM 421906108 123,576 3,154,852 SH   SOLE   2,421,189 0 733,663
Healthstream, Inc. COM 42222N103 56,072 2,238,414 SH   SOLE   1,605,434 0 632,980
HEICO Corporation COM 422806109 106,464 1,379,958 SH   SOLE   1,037,248 0 342,710
Henry Schein, Inc. COM 806407102 17,882 117,867 SH   SOLE   71,344 0 46,523
Heska Corporation COM 42805e306 4,894 68,357 SH   SOLE   52,123 0 16,234
Hormel Foods Corp. COM 440452100 239 6,857 SH   SOLE   6,857 0 0
IHS Markit Ltd. COM G47567105 61,154 1,727,017 SH   SOLE   1,351,490 0 375,527
Illinois Tool Works, Inc. COM 452308109 4,244 34,660 SH   SOLE   34,310 0 350
InnerWorkings, Inc. COM 45773Y105 34,693 3,522,150 SH   SOLE   2,409,702 0 1,112,448
Inovalon Holdings, Inc. Class COM 45781D101 31,788 3,086,223 SH   SOLE   2,385,325 0 700,898
Intel Corporation COM 458140100 2,839 78,278 SH   SOLE   73,882 0 4,396
International Flavors & Fragra COM 459506101 39,864 338,317 SH   SOLE   264,443 0 73,874
Ishares Core S&P 500 Etf COM 464287200 28,290 125,737 SH   SOLE   125,737 0 0
Ishares Core US Growth ETF COM 464287671 1,680 39,147 SH   SOLE   1,166 0 37,981
iShares Russell Midcap ETF COM 464287499 300 1,679 SH   SOLE   1,679 0 0
Ishares Tr Russell 1000 COM 464287622 514 4,126 SH   SOLE   4,126 0 0
Ishares Tr Russell 1000 Growth COM 464287614 531 5,058 SH   SOLE   5,058 0 0
Ishares Tr Russell 2000 COM 464287655 10,269 76,148 SH   SOLE   72,548 0 3,600
Ishares Tr Russell 2000 Growth COM 464287648 4,442 28,858 SH   SOLE   6,482 0 22,376
Johnson & Johnson COM 478160104 3,443 29,882 SH   SOLE   28,930 0 952
JPMorgan Chase & Co. COM 46625H100 913 10,575 SH   SOLE   9,465 0 1,110
Linear Technology Corporation COM 535678106 809 12,977 SH   SOLE   12,867 0 110
LKQ Corporation COM 501889208 51,023 1,664,684 SH   SOLE   1,246,134 0 418,550
MAXIMUS, Inc. COM 577933104 69,818 1,251,449 SH   SOLE   889,837 0 361,612
Mednax, Inc. COM 58502B106 61,588 923,911 SH   SOLE   727,067 0 196,844
Medtronic plc COM G5960L103 17,368 243,831 SH   SOLE   85,286 0 158,545
Microsoft Corporation COM 594918104 58,905 947,937 SH   SOLE   899,237 0 48,700
Middleby Corporation COM 596278101 33,038 256,488 SH   SOLE   153,540 0 102,948
Mobile Mini, Inc. COM 60740F105 28,634 946,592 SH   SOLE   739,111 0 207,481
National Instruments Corporati COM 636518102 181,923 5,902,746 SH   SOLE   4,604,149 0 1,298,597
Neogen Corporation COM 640491106 83,887 1,271,010 SH   SOLE   977,928 0 293,082
Nextera Energy Inc. COM 65339F101 226 1,892 SH   SOLE   1,142 0 750
Novadaq Technologies, Inc. COM 66987G102 23,357 3,294,361 SH   SOLE   2,359,668 0 934,693
Paccar Inc. COM 693718108 367 5,743 SH   SOLE   5,743 0 0
Patterson Companies, Inc. COM 703395103 32,794 799,275 SH   SOLE   608,310 0 190,965
Paychex, Inc. COM 704326107 2,546 41,812 SH   SOLE   41,362 0 450
Paylocity Holding Corp. COM 70438v106 26,709 890,015 SH   SOLE   684,784 0 205,231
Pegasystems, Inc. COM 705573103 48,012 1,333,672 SH   SOLE   1,021,367 0 312,305
PepsiCo, Inc. COM 713448108 3,154 30,146 SH   SOLE   29,885 0 261
Power Integrations, Inc. COM 739276103 41,051 605,033 SH   SOLE   452,144 0 152,889
PRA Group, Inc. COM 69354N106 123,537 3,159,517 SH   SOLE   2,413,264 0 746,253
Praxair, Inc. COM 74005P104 21,707 185,229 SH   SOLE   176,662 0 8,567
Procter & Gamble Company COM 742718109 2,119 25,200 SH   SOLE   24,930 0 270
Pros Holdings, Inc. COM 74346Y103 49,918 2,319,600 SH   SOLE   1,630,225 0 689,375
Proto Labs, Inc. COM 743713109 102,542 1,996,928 SH   SOLE   1,558,425 0 438,503
Qualcomm, Inc. COM 747525103 21,833 334,858 SH   SOLE   312,000 0 22,858
Reckitt Benckiser Group ADR COM 756255204 16,569 973,674 SH   SOLE   958,558 0 15,116
Ritchie Bros. Auctioneers, Inc COM 767744105 108,321 3,185,913 SH   SOLE   2,495,753 0 690,160
Roche Holding Ltd. ADR COM 771195104 23,683 827,877 SH   SOLE   787,120 0 40,757
Rollins, Inc. COM 775711104 61,981 1,834,847 SH   SOLE   1,488,457 0 346,390
Roper Technologies, Inc. COM 776696106 284 1,549 SH   SOLE   1,544 0 5
Rydex ETF Trust Gug S&p500 Pu COM 78355W403 585 6,996 SH   SOLE   6,996 0 0
Salesforce.com, Inc. COM 79466L302 23,180 338,589 SH   SOLE   316,006 0 22,583
Schlumberger NV COM 806857108 3,386 40,329 SH   SOLE   39,872 0 457
Spdr S&P 500 Etf COM 78462F103 3,536 15,821 SH   SOLE   15,821 0 0
SPS Commerce, Inc. COM 78463M107 59,016 844,413 SH   SOLE   647,820 0 196,593
Starbucks Corporation COM 855244109 48,430 872,304 SH   SOLE   822,334 0 49,970
Stericycle, Inc. COM 858912108 40,723 528,594 SH   SOLE   409,582 0 119,012
Stratasys Ltd. COM M85548101 29,543 1,786,175 SH   SOLE   1,358,457 0 427,718
Stryker Corp Com COM 863667101 228 1,900 SH   SOLE   1,900 0 0
Target Corporation COM 87612E106 3,841 53,175 SH   SOLE   52,688 0 487
Tile Shop Holdings, Inc. COM 88677Q109 31,865 1,629,924 SH   SOLE   1,249,996 0 379,928
U.S. Physical Therapy, Inc. COM 90337L108 30,322 431,931 SH   SOLE   334,038 0 97,893
Ultimate Software Group, Inc. COM 90385D107 140,113 768,377 SH   SOLE   575,402 0 192,975
United Natural Foods, Inc. COM 911163103 118,700 2,487,418 SH   SOLE   1,875,004 0 612,414
UnitedHealth Group, Inc. COM 91324P102 35,768 223,492 SH   SOLE   208,218 0 15,274
US Bancorp Del Com COM 902973304 2,391 46,539 SH   SOLE   46,539 0 0
VANGUARD INDEX FDS EXTEND MKT COM 922908652 3,825 39,881 SH   SOLE   0 0 39,881
Veeva Systems, Inc. Class A COM 922475108 86,889 2,134,872 SH   SOLE   1,600,553 0 534,319
Verint Systems, Inc. COM 92343X100 57,647 1,635,385 SH   SOLE   1,207,158 0 428,227
Verisk Analytics, Inc. COM 92345Y106 55,958 689,388 SH   SOLE   516,477 0 172,911
WABCO Holdings, Inc. COM 92927K102 19,855 187,049 SH   SOLE   115,578 0 71,471
WageWorks, Inc. COM 930427109 32,722 451,341 SH   SOLE   345,840 0 105,501
Wal-Mart Stores, Inc. COM 931142103 2,221 32,130 SH   SOLE   31,815 0 315
Walgreens Boots Alliance, Inc. COM 931427108 42,999 519,565 SH   SOLE   497,954 0 21,611
Wells Fargo & Company COM 949746101 389 7,066 SH   SOLE   4,375 0 2,691
Whole Foods Market, Inc. COM 966837106 10,851 352,758 SH   SOLE   320,995 0 31,763
ZELTIQ Aesthetics, Inc. COM 98933Q108 57,466 1,320,440 SH   SOLE   944,667 0 375,773
Alger Fds Ii Alger Spctra I COM 015566300 299 17,775 SH   SOLE   17,775 0 0
Dodge & Cox Stk Fd Com COM 256219106 512 2,780 SH   SOLE   1,171 0 1,609
Fidelity Concord Str T Sp 500 COM 315911701 2,035 25,970 SH   SOLE   10,243 0 15,727
Growth Fd Amer Inc Com COM 399874106 696 16,548 SH   SOLE   16,548 0 0
RB All Cap Growth Fund Investo COM 46141P305 451 31,590 SH   SOLE   31,590 0 0
Riverbridge Growth Fund - Inst COM 46141P404 4,537 314,644 SH   SOLE   314,644 0 0
Third Ave Tr Real Estate Fd COM 884116401 210 7,024 SH   SOLE   7,024 0 0
Vanguard Index Tr 500 Index Ad COM 922908710 6,850 33,159 SH   SOLE   0 0 33,159
Vanguard Index Trust 500 Index COM 922908108 7,076 34,253 SH   SOLE   22,708 0 11,545