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
3D SYSTEMS CORP COM 88554D205 111,537 1,865,174 SH   SOLE   1,865,174 0 0
3M CO COM 88579Y101 611 4,265 SH   SOLE   4,265 0 0
ABBOTT LABORATORIES COM 002824100 481 11,750 SH   SOLE   11,750 0 0
ABBVIE INC COM 00287Y109 529 9,366 SH   SOLE   9,366 0 0
ACTUANT CORP A COM 00508X203 1,499 43,370 SH   SOLE   43,370 0 0
ALTERA CORP COM 021441100 338 9,718 SH   SOLE   9,718 0 0
AMBER ROAD INC COM 02318y108 911 56,451 SH   SOLE   56,451 0 0
AMERICAN TOWER CORP COM 03027X100 85,758 953,074 SH   SOLE   953,074 0 0
ANADARKO PETROLEUM CORP COM 032511107 580 5,300 SH   SOLE   5,300 0 0
ANSYS INC COM 03662Q105 174,267 2,298,431 SH   SOLE   2,298,431 0 0
APACHE CORP COM 037411105 238 2,361 SH   SOLE   2,361 0 0
APPLE COMPUTER INC COM 037833100 1,066 11,473 SH   SOLE   11,473 0 0
APPLIED MINERALS COM 03823m100 134 157,600 SH   SOLE   157,600 0 0
ARCH COAL INC COM 039380100 55 15,000 SH   SOLE   15,000 0 0
ATRION CORP COM 049904105 1,747 5,360 SH   SOLE   5,360 0 0
AUTOMATIC DATA PROCESSING COM 053015103 2,527 31,875 SH   SOLE   31,875 0 0
BECTON DICKINSON & CO COM 075887109 260 2,200 SH   SOLE   2,200 0 0
BERKSHIRE HATHAWAY INC COM 084670108 1,329 7 SH   SOLE   7 0 0
BERKSHIRE HATHAWAY INC. DEL CL COM 084670702 3,070 24,260 SH   SOLE   24,260 0 0
CANADIAN NATIONAL RAILROAD CO COM 136375102 1,300 20,000 SH   SOLE   20,000 0 0
CAPITAL ONE FINANCIAL COM 14040H105 2,225 26,938 SH   SOLE   26,938 0 0
CAREFUSION CORPORATION COM 14170T101 45,360 1,022,780 SH   SOLE   1,022,780 0 0
CARMAX INC COM 143130102 58,467 1,124,156 SH   SOLE   1,124,156 0 0
CATERPILLAR INC COM 149123101 245 2,256 SH   SOLE   2,256 0 0
CELGENE CORP COM 151020104 115,883 1,349,360 SH   SOLE   1,349,360 0 0
CHEVRON CORP COM 166764100 1,466 11,231 SH   SOLE   11,231 0 0
CISCO SYSTEMS INC COM 17275R102 2,062 82,991 SH   SOLE   82,991 0 0
COCA COLA CO COM 191216100 1,151 27,162 SH   SOLE   27,162 0 0
COLFAX CORP COM 194014106 224 3,000 SH   SOLE   3,000 0 0
COLGATE-PALMOLIVE COM 194162103 682 10,000 SH   SOLE   10,000 0 0
COMCAST CORP - A COM 20030N101 678 12,625 SH   SOLE   12,625 0 0
COMCAST CORP - A - SPL COM 20030N200 4,237 79,447 SH   SOLE   79,447 0 0
CONCHO RESOURCES INC COM 20605P101 97,652 675,791 SH   SOLE   675,791 0 0
CONCUR TECHNOLOGIES, INC. COM 206708109 83,782 897,601 SH   SOLE   897,601 0 0
CORE LABORATORIES NV COM N22717107 58,620 350,890 SH   SOLE   350,890 0 0
COSTAR GROUP INC. COM 22160n109 81,689 516,466 SH   SOLE   516,466 0 0
CROWN CASTLE INTL CORP COM 228227104 4,151 55,899 SH   SOLE   55,899 0 0
DEALERTRACK TECHNOLOGIES INC COM 242309102 78,323 1,727,466 SH   SOLE   1,727,466 0 0
DEERE & CO COM 244199105 242 2,673 SH   SOLE   2,673 0 0
DENTSPLY INTL COM 249030107 281 5,933 SH   SOLE   5,933 0 0
DISCOVER FINANCIAL SERVICES COM 254709108 102,394 1,652,043 SH   SOLE   1,652,043 0 0
DONALDSON INC COM 257651109 4,122 97,405 SH   SOLE   97,405 0 0
DORMAN PRODUCTS INC COM 258278100 12,701 257,516 SH   SOLE   257,516 0 0
DOUGLAS DYNAMICS INC COM 25960R105 711 40,324 SH   SOLE   40,324 0 0
DUKE REALTY CORP COM 264411505 282 15,550 SH   SOLE   15,550 0 0
EAST WEST BANCORP INC COM 27579R104 535 15,300 SH   SOLE   15,300 0 0
ECOLAB INC COM 278865100 121,500 1,091,250 SH   SOLE   1,091,250 0 0
EINSTEIN NOAH RESTAURANT GP IN COM 28257u104 555 34,575 SH   SOLE   34,575 0 0
ELI LILLY & CO COM 532457108 594 9,554 SH   SOLE   9,554 0 0
ELLIE MAE INC COM 28849P100 1,840 59,100 SH   SOLE   59,100 0 0
EMERSON COM 291011104 508 7,651 SH   SOLE   7,651 0 0
ENTERPRISE PRODUCTS PARTNERS L COM 293792107 654 8,350 SH   SOLE   8,350 0 0
ENVESTNET INC COM 29404K106 1,102 22,536 SH   SOLE   22,536 0 0
EQT CORPORATION COM 26884L109 5,659 52,936 SH   SOLE   52,936 0 0
EQUITY RESIDENTIAL PROPERTYS I COM 29476l107 394 6,248 SH   SOLE   6,248 0 0
EXAMWORKS GROUP INC. COM 30066a105 62,650 1,974,465 SH   SOLE   1,974,465 0 0
EXPEDITORS INTERNATIONAL COM 302130109 68,841 1,558,900 SH   SOLE   1,558,900 0 0
EXPONENT INC. COM 30214U102 40,635 548,303 SH   SOLE   548,303 0 0
EXPRESS SCRIPTS INC COM 30219G108 1,351 19,487 SH   SOLE   19,487 0 0
EXXON MOBIL CORP COM 30231G102 2,020 20,060 SH   SOLE   20,060 0 0
FASTENAL CO COM 311900104 268,441 5,424,147 SH   SOLE   5,424,147 0 0
FINANCIAL ENGINES INC COM 317485100 36,702 810,549 SH   SOLE   810,549 0 0
FISERV INC COM 337738108 4,180 69,298 SH   SOLE   69,298 0 0
FORTINET INC COM 34959e109 1,236 49,189 SH   SOLE   49,189 0 0
FREEPORT MCMORAN COPPER & GOLD COM 35671D857 647 17,714 SH   SOLE   17,714 0 0
GENERAL ELECTRIC COM 369604103 3,372 128,306 SH   SOLE   128,306 0 0
GENUINE PARTS COMPANY COM 372460105 263 2,999 SH   SOLE   2,999 0 0
GILEAD SCIENCES INC. COM 375558103 577 6,960 SH   SOLE   6,960 0 0
GOOGLE INC CL C COM 38259P706 259 450 SH   SOLE   450 0 0
GOOGLE INC CLASS A COM 38259P508 263 450 SH   SOLE   450 0 0
HCP INC COM 40414L109 4,417 106,746 SH   SOLE   106,746 0 0
HEALTHCARE SERVICES GROUP INC COM 421906108 66,705 2,265,779 SH   SOLE   2,265,779 0 0
HESS CORPORATION COM 42809h107 346 3,502 SH   SOLE   3,502 0 0
HIBBETT SPORTS INC COM 428567101 548 10,113 SH   SOLE   10,113 0 0
HOME DEPOT COM 437076102 243 2,999 SH   SOLE   2,999 0 0
HOVNANIAN ENTERPRISES INC COM 442487203 232 45,000 SH   SOLE   45,000 0 0
ILLINOIS TOOL WORKS COM 452308109 210 2,400 SH   SOLE   2,400 0 0
ILLUMINA INC COM 452327109 34,974 195,889 SH   SOLE   195,889 0 0
IMAX CORP COM 45245E109 76,858 2,698,664 SH   SOLE   2,698,664 0 0
INTEL CORP COM 458140100 14,310 463,118 SH   SOLE   463,118 0 0
INTERMAP TECHNOLOGIES CORP COM 458977204 17 75,000 SH   SOLE   75,000 0 0
INTL BUSINESS MACH CORP COM 459200101 2,262 12,477 SH   SOLE   12,477 0 0
INTUITIVE SURGICAL INC COM 46120e602 47,293 114,845 SH   SOLE   114,845 0 0
INVENTURE FOODS INC COM 461212102 209 18,536 SH   SOLE   18,536 0 0
J P MORGAN CHASE & CO COM 46625H100 298 5,169 SH   SOLE   5,169 0 0
JACOBS ENGINEERING CP INC COM 469814107 78,771 1,478,438 SH   SOLE   1,478,438 0 0
JAMBA, INC. COM 47023A101 181 15,000 SH   SOLE   15,000 0 0
JOHNSON & JOHNSON COM 478160104 10,693 102,205 SH   SOLE   102,205 0 0
LABORATORY CORP OF AMERICA HOL COM 50540R409 4,140 40,427 SH   SOLE   40,427 0 0
LAKE SHORE GOLD CORP COM 510728108 23 25,000 SH   SOLE   25,000 0 0
LANDAUER, INC. COM 51476k103 251 5,987 SH   SOLE   5,987 0 0
LINCOLN NATL CORP COM 534187109 285 5,536 SH   SOLE   5,536 0 0
LKQ CORP COM 501889208 135,120 5,062,555 SH   SOLE   5,062,555 0 0
LYNAS CORP LTD COM Q5683J103 16 135,000 SH   SOLE   135,000 0 0
M&T BANK CORP COM 55261F104 389 3,138 SH   SOLE   3,138 0 0
MACY'S, INC. COM 55616P104 340 5,863 SH   SOLE   5,863 0 0
MAG SILVER CORP COM 55903Q104 851 90,000 SH   SOLE   90,000 0 0
MAGELLAN MIDSTREAM PARTNERS LP COM 559080106 336 4,000 SH   SOLE   4,000 0 0
MARKEL CORP COM 570535104 152,053 231,915 SH   SOLE   231,915 0 0
MASTERCARD INC CL A COM 57636Q104 1,848 25,150 SH   SOLE   25,150 0 0
McCORMICK & CO COM 579780206 1,032 14,420 SH   SOLE   14,420 0 0
MCEWEN MINING INC COM 58039P107 242 84,000 SH   SOLE   84,000 0 0
MERCK & CO COM 58933Y105 1,143 19,753 SH   SOLE   19,753 0 0
MERIDIAN BIOSCIENCE INC. COM 589584101 264 12,800 SH   SOLE   12,800 0 0
MICROSOFT CORP COM 594918104 2,469 59,201 SH   SOLE   59,201 0 0
MIDDLEBY CORP COM 596278101 1,672 20,208 SH   SOLE   20,208 0 0
MONRO MUFFLER BRAKE COM 610236101 493 9,268 SH   SOLE   9,268 0 0
MOODYS CORP COM 615369105 121,783 1,389,262 SH   SOLE   1,389,262 0 0
NANOSPHERE INC COM 63009f105 71 45,000 SH   SOLE   45,000 0 0
NATIONAL AMERICAN UNIV HOLDING COM 63245Q105 46 15,000 SH   SOLE   15,000 0 0
NATIONAL INFORMATION CONSORTIU COM 62914b100 1,071 67,597 SH   SOLE   67,597 0 0
NEOGEN CORP COM 640491106 397 9,800 SH   SOLE   9,800 0 0
NESTLE S.A. COM 641069406 261 3,375 SH   SOLE   3,375 0 0
NYMOX PHARMACEUTICAL CORP COM 67076p102 111 22,500 SH   SOLE   22,500 0 0
O REILLY AUTOMOTIVE INC COM 67103H107 16,531 109,766 SH   SOLE   109,766 0 0
ONEBEACON INSURANCE GP COM G67742109 407 26,163 SH   SOLE   26,163 0 0
PANERA BREAD CO COM 69840W108 22,425 149,667 SH   SOLE   149,667 0 0
PAYCHEX COM 704326107 4,466 107,462 SH   SOLE   107,462 0 0
PEPSICO INC COM 713448108 373 4,173 SH   SOLE   4,173 0 0
PFIZER INC COM 717081103 1,196 40,299 SH   SOLE   40,299 0 0
PHILIP MORRIS INTL COM 718172109 487 5,776 SH   SOLE   5,776 0 0
PINNACLE WEST CAPITOL CORP COM 723484101 254 4,400 SH   SOLE   4,400 0 0
PNC FINANCIAL SVCS INC COM 693475105 2,341 26,290 SH   SOLE   26,290 0 0
POTASH CORP OF SASKATCHEWAN COM 73755L107 29,903 787,745 SH   SOLE   787,745 0 0
PRECISION CASTPARTS CORP COM 740189105 454 1,800 SH   SOLE   1,800 0 0
PRICE SMART INC COM 741511109 40,026 459,857 SH   SOLE   459,857 0 0
PROCTER & GAMBLE CO COM 742718109 21,133 268,906 SH   SOLE   268,906 0 0
QUALCOMM INC COM 747525103 143,235 1,808,523 SH   SOLE   1,808,523 0 0
QUANTA SERVICES INC COM 74762e102 2,963 85,691 SH   SOLE   85,691 0 0
RANGE RESOURCES CORP COM 75281A109 58,245 669,867 SH   SOLE   669,867 0 0
RAVEN INDUSTRIES, INC. COM 754212108 319 9,629 SH   SOLE   9,629 0 0
RED HAT INC. COM 756577102 121,255 2,193,873 SH   SOLE   2,193,873 0 0
RENAISSANCE RE HOLDINGS LTD COM G7496G103 786 7,350 SH   SOLE   7,350 0 0
ROPER INDUSTRIES, INC COM 776696106 103,939 711,861 SH   SOLE   711,861 0 0
SBA COMMUNICATIONS CORP COM 78388J106 1,562 15,271 SH   SOLE   15,271 0 0
SCHLUMBERGER LTD COM 806857108 135,882 1,152,030 SH   SOLE   1,152,030 0 0
SEI INVESTMENTS CO COM 784117103 117,604 3,588,764 SH   SOLE   3,588,764 0 0
SIGNET JEWELERS LTD COM g81276100 84,644 765,390 SH   SOLE   765,390 0 0
SILVER WHEATON CORP COM 828336107 512 19,500 SH   SOLE   19,500 0 0
SMITH & NEPHEW PLC COM 83175M205 268 3,000 SH   SOLE   3,000 0 0
SOTHERLY HOTELS, INC COM 55302L102 107 13,625 SH   SOLE   13,625 0 0
SOUTHWESTERN ENERGY CO COM 845467109 73,557 1,616,989 SH   SOLE   1,616,989 0 0
STERICYCLE INC COM 858912108 127,751 1,078,798 SH   SOLE   1,078,798 0 0
STRYKER CORP COM 863667101 319 3,784 SH   SOLE   3,784 0 0
T ROWE PRICE GROUP INC COM 74144T108 19,059 225,788 SH   SOLE   225,788 0 0
TANGOE INC COM 87582Y108 19,706 1,308,496 SH   SOLE   1,308,496 0 0
TECHNE CORP COM 878377100 10,751 116,144 SH   SOLE   116,144 0 0
TELEFLEX INC COM 879369106 290 2,750 SH   SOLE   2,750 0 0
TESLA MOTORS INC COM 88160R101 210 875 SH   SOLE   875 0 0
TRIMBLE NAVIGATION LTD COM 896239100 149,745 4,052,634 SH   SOLE   4,052,634 0 0
TYLER TECHNOLOGIES INC COM 902252105 48,207 528,532 SH   SOLE   528,532 0 0
U.S. BANCORP COM 902973304 1,234 28,486 SH   SOLE   28,486 0 0
ULTIMATE SOFTWARE INC COM 90385d107 222 1,610 SH   SOLE   1,610 0 0
UNDER ARMOUR, INC COM 904311107 506 8,500 SH   SOLE   8,500 0 0
UNION PACIFIC CORP COM 907818108 204 2,050 SH   SOLE   2,050 0 0
UNITED TECHNOLOGIES CORP COM 913017109 470 4,071 SH   SOLE   4,071 0 0
VENTAS INC COM 92276f100 2,490 38,853 SH   SOLE   38,853 0 0
VERISK ANALYTICS COM 92345Y106 81,711 1,361,399 SH   SOLE   1,361,399 0 0
VERIZON COMMUNICATIONS COM 92343V104 270 5,513 SH   SOLE   5,513 0 0
VF CORP COM 918204108 252 4,000 SH   SOLE   4,000 0 0
VISA INC COM 92826C839 109,786 521,027 SH   SOLE   521,027 0 0
WAGEWORKS INC COM 930427109 98,682 2,046,922 SH   SOLE   2,046,922 0 0
WALT DISNEY CO COM 254687106 765 8,919 SH   SOLE   8,919 0 0
WASTE CONNECTIONS INC COM 941053100 122,053 2,513,968 SH   SOLE   2,513,968 0 0
WELLS FARGO & CO COM 949746101 371 7,055 SH   SOLE   7,055 0 0
WHOLE FOODS MARKET COM 966837106 610 15,800 SH   SOLE   15,800 0 0
WR BERKLEY CORP COM 084423102 3,224 69,628 SH   SOLE   69,628 0 0
ZOE'S KITCHEN INC COM 98979J109 365 10,618 SH   SOLE   10,618 0 0
ISHARES TR MSCI EAFE INDEX FD ETFS 464287465 368 5,389 SH   SOLE   5,389 0 0
VANGUARD DIVIDEND ETFS 921908844 879 11,275 SH   SOLE   11,275 0 0
VANGUARD FTSE ALL-WORLD EX-US ETFS 922042775 2,838 54,272 SH   SOLE   54,272 0 0
VANGUARD FTSE EMERGING MARKETS ETFS 922042858 557 12,925 SH   SOLE   12,925 0 0
VANGUARD HIGH DIVIDEND YIELD E ETFS 921946406 317 4,775 SH   SOLE   4,775 0 0
VANGUARD INDEX REIT ETF ETFS 922908553 423 5,655 SH   SOLE   5,655 0 0