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
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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 48,089 1,212,524 SH   SOLE   864,925 0 347,599
3M Company COM 88579Y101 24,175 126,354 SH   SOLE   124,118 0 2,236
Acuity Brands, Inc. COM 00508Y102 69,212 339,275 SH   SOLE   267,454 0 71,821
Advisory Board Company COM 00762W107 314 6,707 SH   SOLE   4,782 0 1,925
Alphabet, Inc. Class A COM 02079K305 18,452 21,764 SH   SOLE   19,636 0 2,128
Alphabet, Inc. Class C COM 02079K107 15,556 18,752 SH   SOLE   18,217 0 535
Amazon.com, Inc. COM 023135106 45,801 51,663 SH   SOLE   48,490 0 3,173
Ansys, Inc. COM 03662Q105 62,741 587,075 SH   SOLE   436,685 0 150,390
Apple Inc. COM 037833100 5,989 41,692 SH   SOLE   32,542 0 9,150
athenahealth, Inc. COM 04685W103 119,129 1,057,142 SH   SOLE   813,272 0 243,870
Beacon Roofing Supply, Inc. COM 073685109 86,310 1,755,694 SH   SOLE   1,377,758 0 377,936
Berkshire Hathaway Inc. Class COM 084670702 274 1,645 SH   SOLE   1,070 0 575
Bio-Techne Corporation COM 09073M104 61,478 604,797 SH   SOLE   418,958 0 185,839
Burberry Group ADR COM 12082W204 13,526 627,437 SH   SOLE   618,552 0 8,885
Cabot Microelectronics Corpora COM 12709P103 23,296 304,091 SH   SOLE   230,455 0 73,636
Calavo Growers, Inc. COM 128246105 21,219 350,149 SH   SOLE   272,014 0 78,135
Cardinal Health, Inc. COM 14149y108 1,659 20,346 SH   SOLE   20,116 0 230
Cass Information Systems, Inc. COM 14808P109 30,514 461,636 SH   SOLE   356,299 0 105,337
Cerner Corporation COM 156782104 19,363 329,017 SH   SOLE   310,622 0 18,395
ChannelAdvisor Corporation COM 159179100 18,631 1,670,973 SH   SOLE   1,152,069 0 518,904
Cheesecake Factory, Inc. COM 163072101 33,712 532,070 SH   SOLE   406,290 0 125,780
Chemed Corporation COM 16359R103 134,654 737,064 SH   SOLE   557,766 0 179,298
Cisco Systems, Inc. COM 17275R102 21,919 648,505 SH   SOLE   640,842 0 7,663
Coca Cola Co Com COM 191216100 246 5,786 SH   SOLE   4,704 0 1,082
Cognex Corporation COM 192422103 80,115 954,322 SH   SOLE   661,145 0 293,177
Colgate-Palmolive Company COM 194162103 2,846 38,886 SH   SOLE   38,481 0 405
CoStar Group, Inc. COM 22160N109 138,815 669,890 SH   SOLE   502,876 0 167,014
Cree, Inc. COM 225447101 1,415 52,951 SH   SOLE   24,865 0 28,086
Digi International, Inc. COM 253798102 18,937 1,591,380 SH   SOLE   1,222,177 0 369,203
Diplomat Pharmacy, Inc. COM 25456K101 23,355 1,464,286 SH   SOLE   1,000,210 0 464,076
Dorman Products, Inc. COM 258278100 67,378 820,384 SH   SOLE   564,203 0 256,181
Ecolab, Inc. COM 278865100 49,910 398,197 SH   SOLE   375,665 0 22,532
Ellie Mae, Inc. COM 28849P100 75,106 749,035 SH   SOLE   531,224 0 217,811
ExlService Holdings, Inc. COM 302081104 48,034 1,014,237 SH   SOLE   709,968 0 304,269
Exponent, Inc. COM 30214u102 31,181 523,606 SH   SOLE   394,714 0 128,892
Exxon Mobil Corporation COM 30231G102 225 2,745 SH   SOLE   2,131 0 614
Fastenal Company COM 311900104 97,438 1,891,992 SH   SOLE   1,464,622 0 427,370
FedEx Corporation COM 31428X106 240 1,228 SH   SOLE   1,228 0 0
Financial Engines, Inc. COM 317485100 63,232 1,451,943 SH   SOLE   1,028,910 0 423,033
Fiserv, Inc. COM 337738108 59,452 515,581 SH   SOLE   487,234 0 28,347
Five Below, Inc. COM 33829M101 98,530 2,274,988 SH   SOLE   1,720,044 0 554,944
Freshpet, Inc. COM 358039105 24,078 2,188,905 SH   SOLE   1,659,743 0 529,162
General Electric Company COM 369604103 2,597 87,141 SH   SOLE   84,438 0 2,703
Gentex Corporation COM 371901109 102,661 4,812,976 SH   SOLE   3,823,531 0 989,445
Grand Canyon Education, Inc. COM 38526M106 197,687 2,760,608 SH   SOLE   2,121,459 0 639,149
Healthcare Services Group, Inc COM 421906108 130,858 3,036,864 SH   SOLE   2,312,890 0 723,974
Healthstream, Inc. COM 42222N103 51,996 2,145,925 SH   SOLE   1,524,215 0 621,710
HEICO Corporation COM 422806109 116,102 1,331,443 SH   SOLE   992,813 0 338,630
Henry Schein, Inc. COM 806407102 19,383 114,036 SH   SOLE   68,048 0 45,988
Heska Corporation COM 42805e306 25,618 244,031 SH   SOLE   184,941 0 59,090
Hormel Foods Corp. COM 440452100 203 5,855 SH   SOLE   5,855 0 0
IHS Markit Ltd. COM G47567105 70,520 1,681,043 SH   SOLE   1,309,824 0 371,219
Illinois Tool Works Inc. COM 452308109 2,650 20,004 SH   SOLE   19,654 0 350
InnerWorkings, Inc. COM 45773Y105 33,610 3,374,489 SH   SOLE   2,276,523 0 1,097,966
Inovalon Holdings, Inc. Class COM 45781D101 40,539 3,217,399 SH   SOLE   2,478,755 0 738,644
Intel Corporation COM 458140100 2,720 75,419 SH   SOLE   71,023 0 4,396
International Flavors & Fragra COM 459506101 43,779 330,336 SH   SOLE   257,526 0 72,810
Ishares Core S&P 500 Etf COM 464287200 777 3,276 SH   SOLE   3,276 0 0
iShares Russell Midcap ETF COM 464287499 312 1,666 SH   SOLE   1,666 0 0
Ishares Tr Russell 1000 COM 464287622 553 4,212 SH   SOLE   4,212 0 0
Ishares Tr Russell 1000 Growth COM 464287614 536 4,713 SH   SOLE   4,713 0 0
Ishares Tr Russell 2000 COM 464287655 1,503 10,933 SH   SOLE   6,333 0 4,600
Ishares Tr Russell 2000 Growth COM 464287648 596 3,686 SH   SOLE   228 0 3,458
Johnson & Johnson COM 478160104 3,651 29,312 SH   SOLE   28,359 0 953
JPMorgan Chase & Co. COM 46625H100 929 10,575 SH   SOLE   9,465 0 1,110
Knight Transportation, Inc. COM 499064103 30,001 956,956 SH   SOLE   727,224 0 229,732
LKQ Corporation COM 501889208 47,181 1,611,933 SH   SOLE   1,200,601 0 411,332
MAXIMUS, Inc. COM 577933104 74,563 1,198,759 SH   SOLE   840,343 0 358,416
Mednax, Inc. COM 58502B106 62,466 900,352 SH   SOLE   706,377 0 193,975
Medtronic plc COM G5960L103 19,744 245,079 SH   SOLE   86,534 0 158,545
Microsoft Corporation COM 594918104 61,432 932,760 SH   SOLE   884,136 0 48,624
Middleby Corporation COM 596278101 33,478 245,348 SH   SOLE   144,171 0 101,177
Mobile Mini, Inc. COM 60740F105 27,780 910,832 SH   SOLE   703,417 0 207,415
National Instruments Corporati COM 636518102 185,952 5,711,068 SH   SOLE   4,424,578 0 1,286,490
Neogen Corporation COM 640491106 80,651 1,230,369 SH   SOLE   941,596 0 288,773
NextEra Energy, Inc. COM 65339F101 243 1,892 SH   SOLE   1,142 0 750
Novadaq Technologies, Inc. COM 66987G102 25,469 3,269,494 SH   SOLE   2,294,431 0 975,063
Oracle Corporation COM 68389X105 223 5,000 SH   SOLE   5,000 0 0
Paccar Inc. COM 693718108 386 5,743 SH   SOLE   5,743 0 0
Patterson Companies, Inc. COM 703395103 35,450 783,777 SH   SOLE   594,778 0 188,999
Paychex, Inc. COM 704326107 2,359 40,059 SH   SOLE   39,609 0 450
Paylocity Holding Corp. COM 70438v106 33,299 862,003 SH   SOLE   653,463 0 208,540
Pegasystems, Inc. COM 705573103 56,071 1,278,690 SH   SOLE   968,170 0 310,520
PepsiCo, Inc. COM 713448108 3,268 29,214 SH   SOLE   28,948 0 266
Power Integrations, Inc. COM 739276103 38,166 580,474 SH   SOLE   428,297 0 152,177
PRA Group, Inc. COM 69354N106 101,963 3,075,807 SH   SOLE   2,333,875 0 741,932
Praxair, Inc. COM 74005P104 21,743 183,331 SH   SOLE   174,768 0 8,563
Procter & Gamble Company COM 742718109 2,195 24,425 SH   SOLE   24,155 0 270
Pros Holdings, Inc. COM 74346Y103 54,107 2,236,754 SH   SOLE   1,549,216 0 687,538
Proto Labs, Inc. COM 743713109 103,306 2,021,642 SH   SOLE   1,572,223 0 449,419
Qualcomm, Inc. COM 747525103 19,262 335,924 SH   SOLE   313,005 0 22,919
Reckitt Benckiser Group ADR COM 756255204 19,363 1,062,620 SH   SOLE   1,047,439 0 15,181
Ritchie Bros. Auctioneers, Inc COM 767744105 101,163 3,074,870 SH   SOLE   2,390,577 0 684,293
Roche Holding Ltd. ADR COM 771195104 28,037 877,688 SH   SOLE   829,659 0 48,029
Rollins, Inc. COM 775711104 66,097 1,780,138 SH   SOLE   1,440,280 0 339,858
Roper Technologies, Inc. COM 776696106 313 1,514 SH   SOLE   1,509 0 5
Rydex ETF Trust Gug S&p500 Pu COM 78355W403 627 6,996 SH   SOLE   6,996 0 0
Salesforce.com, Inc. COM 79466L302 32,527 394,314 SH   SOLE   369,483 0 24,831
Schlumberger NV COM 806857108 3,144 40,254 SH   SOLE   39,797 0 457
Snap-on, Inc. COM 833034101 36,373 215,647 SH   SOLE   172,510 0 43,137
Spdr S&P 500 Etf COM 78462F103 3,264 13,846 SH   SOLE   13,846 0 0
SPS Commerce, Inc. COM 78463M107 47,267 808,114 SH   SOLE   613,565 0 194,549
Starbucks Corporation COM 855244109 50,303 861,508 SH   SOLE   811,445 0 50,063
Stericycle, Inc. COM 858912108 43,509 524,901 SH   SOLE   400,551 0 124,350
Stratasys Ltd. COM M85548101 37,813 1,845,424 SH   SOLE   1,396,516 0 448,908
Stryker Corp Com COM 863667101 250 1,900 SH   SOLE   1,900 0 0
Target Corporation COM 87612E106 2,810 50,912 SH   SOLE   50,424 0 488
Tile Shop Holdings, Inc. COM 88677Q109 30,093 1,563,269 SH   SOLE   1,185,858 0 377,411
U.S. Bancorp COM 902973304 2,309 44,843 SH   SOLE   44,843 0 0
U.S. Physical Therapy, Inc. COM 90337L108 27,345 418,764 SH   SOLE   320,758 0 98,006
Ultimate Software Group, Inc. COM 90385D107 145,156 743,591 SH   SOLE   552,998 0 190,593
United Natural Foods, Inc. COM 911163103 103,980 2,405,270 SH   SOLE   1,798,478 0 606,792
UnitedHealth Group, Inc. COM 91324P102 36,352 221,648 SH   SOLE   206,373 0 15,275
Valspar Corporation COM 920355104 271 2,441 SH   SOLE   2,441 0 0
VANGUARD INDEX FDS EXTEND MKT COM 922908652 1,140 11,408 SH   SOLE   0 0 11,408
Veeva Systems, Inc. Class A COM 922475108 105,554 2,058,387 SH   SOLE   1,531,386 0 527,001
Verint Systems, Inc. COM 92343X100 70,593 1,627,510 SH   SOLE   1,196,761 0 430,749
Verisk Analytics, Inc. COM 92345Y106 54,308 669,309 SH   SOLE   499,442 0 169,867
WABCO Holdings, Inc. COM 92927K102 20,978 178,657 SH   SOLE   108,148 0 70,509
WageWorks, Inc. COM 930427109 31,259 432,357 SH   SOLE   327,926 0 104,431
Wal-Mart Stores, Inc. COM 931142103 2,160 29,970 SH   SOLE   29,655 0 315
Walgreens Boots Alliance, Inc. COM 931427108 43,120 519,202 SH   SOLE   497,679 0 21,523
Wells Fargo & Company COM 949746101 383 6,881 SH   SOLE   4,190 0 2,691
Whole Foods Market, Inc. COM 966837106 10,849 365,035 SH   SOLE   332,071 0 32,964
ZELTIQ Aesthetics, Inc. COM 98933Q108 70,106 1,260,664 SH   SOLE   889,095 0 371,569
Alger Fds Ii Alger Spctra I COM 015566300 332 17,775 SH   SOLE   17,775 0 0
Dodge & Cox Stk Fd Com COM 256219106 532 2,798 SH   SOLE   1,188 0 1,611
Fidelity Concord Str T Sp 500 COM 315911701 2,158 25,970 SH   SOLE   10,243 0 15,727
Growth Fd Amer Inc Com COM 399874106 711 15,635 SH   SOLE   15,635 0 0
JPMORGAN TR II LARGE CAP GR A COM 4812C0506 208 5,905 SH   SOLE   5,905 0 0
RB All Cap Growth Fund Investo COM 46141P305 160 10,418 SH   SOLE   10,418 0 0
Riverbridge Growth Fund - Inst COM 46141P404 5,727 369,718 SH   SOLE   369,718 0 0
Third Ave Tr Real Estate Fd COM 884116401 227 7,024 SH   SOLE   7,024 0 0
Vanguard Index Tr 500 Index Ad COM 922908710 6,273 28,769 SH   SOLE   0 0 28,769
Vanguard Index Trust 500 Index COM 922908108 6,694 30,698 SH   SOLE   19,800 0 10,897