ATS Corp /ATS - ATS

Detailed investor-level table based on 13F positions.

Shareholders (13F)

Quarter: Q1 2026 · Compare: Q4 2025
13D/13G major owners: Ownership tab.
Methodology: Market value and % of portfolio use SEC reported VALUE ($000). For PUT/CALL positions this reflects reported underlying exposure, not premium cash paid/received. Details.
Rows: 0
Investor History Status Shares held Market value ($000) % of portfolio Previous % Rank Change in shares % change in shares Source Date reported
MASON CAPITAL MANAGEMENT LLC History Added to 16,404,170 462,597 75.48% 76.32% 1 +840,602 5.4% Q1 2026 May 15, 2026
ROYAL BANK OF CANADA History Added to 7,761,838 218,884 0.04% 0.03% 2 +117,291 1.53% Q1 2026 May 15, 2026
EdgePoint Investment Group Inc. History Added to 7,168,112 202,081 1.62% 1.56% 3 +279,327 4.05% Q1 2026 May 15, 2026
Beutel, Goodman & Co Ltd. History Reduced 5,454,749 153,259 1.04% 0.99% 4 -382,389 -6.55% Q1 2026 May 15, 2026
Turtle Creek Asset Management Inc. History Reduced 4,896,669 138,086 5.17% 6.84% 5 -745,383 -13.21% Q1 2026 May 19, 2026
VANGUARD GROUP INC History No change 3,397,166 93,581 0.0% 0.0% 6 0 0.0% Q4 2025 Jan 29, 2026
BANK OF MONTREAL /CAN/ History Added to 3,115,360 87,827 0.03% 0.03% 7 +92,667 3.07% Q1 2026 May 13, 2026
FAIRFAX FINANCIAL HOLDINGS LTD/ CAN History No change 2,486,400 69,352 3.57% 3.28% 8 0 0.0% Q1 2026 May 15, 2026
VANGUARD CAPITAL MANAGEMENT LLC History New 2,366,730 66,708 0.0% 9 +2,366,730 New Q1 2026 May 15, 2026
JANUS HENDERSON GROUP PLC History Added to 2,297,214 64,543 0.03% 0.01% 10 +1,435,375 166.55% Q1 2026 May 18, 2026
FMR LLC History Added to 2,277,472 64,193 0.0% 0.0% 11 +159,706 7.54% Q1 2026 May 15, 2026
Connor, Clark & Lunn Investment Management Ltd. History Reduced 2,264,757 63,847 0.15% 0.18% 12 -220,881 -8.89% Q1 2026 May 11, 2026
ACK Asset Management LLC History No change 1,846,196 52,062 6.5% 6.38% 13 0 0.0% Q1 2026 May 15, 2026
FIL Ltd History Added to 1,778,181 50,088 0.04% 0.0% 14 +1,724,612 3219.42% Q1 2026 May 15, 2026
TD Waterhouse Canada Inc. History Added to 1,634,449 46,872 0.14% 0.16% 15 +668,100 69.14% Q1 2026 May 12, 2026
Hill City Capital, LP History No change 1,649,857 46,525 1.66% 1.72% 16 0 0.0% Q1 2026 May 15, 2026
TD ASSET MANAGEMENT INC History Added to 1,422,459 39,966 0.03% 0.03% 17 +229,251 19.21% Q1 2026 May 11, 2026
Vinva Investment Management Ltd History New 2,088,947 36,514 0.45% 18 +2,088,947 New Q1 2026 May 13, 2026
VAN LANSCHOT KEMPEN INVESTMENT MANAGEMENT N.V. History Added to 863,486 33,857 0.3% 0.26% 19 +48,455 5.95% Q1 2026 May 15, 2026
Scheer, Rowlett & Associates Investment Management Ltd. History Reduced 1,181,937 33,320 2.4% 2.32% 20 -44,513 -3.63% Q1 2026 May 11, 2026
Clearbridge Investments, LLC History Reduced 1,091,291 30,774 0.03% 0.02% 21 -20,194 -1.82% Q1 2026 May 13, 2026
Marathon Asset Management Ltd History Reduced 1,093,911 30,733 1.18% 1.16% 22 -3,800 -0.35% Q1 2026 Apr 24, 2026
NORGES BANK History No change 1,079,090 29,726 0.0% 0.0% 23 0 0.0% Q4 2025 Feb 10, 2026
BANK OF AMERICA CORP /DE/ History Reduced 945,875 26,673 0.0% 0.0% 24 -154,506 -14.04% Q1 2026 May 15, 2026
Alberta Investment Management Corp History Reduced 940,191 26,505 0.16% 0.22% 25 -400,074 -29.85% Q1 2026 Apr 28, 2026
MIRAE ASSET GLOBAL ETFS HOLDINGS Ltd. History Reduced 758,313 21,305 0.03% 0.05% 26 -383,522 -33.59% Q1 2026 May 15, 2026
MASSACHUSETTS FINANCIAL SERVICES CO /MA/ History Reduced 533,957 20,936 0.01% 0.0% 27 -24,718 -4.42% Q1 2026 May 14, 2026
VANGUARD FIDUCIARY TRUST CO History New 728,058 20,521 0.01% 28 +728,058 New Q1 2026 May 08, 2026
NATIONAL BANK OF CANADA /FI/ History Added to 648,282 18,112 0.02% 0.01% 29 +229,950 54.97% Q1 2026 May 14, 2026
PRINCIPAL FINANCIAL GROUP INC History Reduced 620,840 17,443 0.01% 0.01% 30 -257,400 -29.31% Q1 2026 May 04, 2026
MACKENZIE FINANCIAL CORP History Reduced 616,504 17,374 0.02% 0.02% 31 -142,476 -18.77% Q1 2026 May 13, 2026
Legal & General Group Plc History Added to 611,689 17,239 0.0% 0.0% 32 +69,666 12.85% Q1 2026 May 08, 2026
1832 Asset Management L.P. History Reduced 401,696 11,327 0.01% 0.02% 33 -416,863 -50.93% Q1 2026 May 14, 2026
PUBLIC SECTOR PENSION INVESTMENT BOARD History Added to 356,837 10,059 0.03% 0.03% 34 +69,008 23.98% Q1 2026 May 13, 2026
CIBC WORLD MARKET INC. History Reduced 346,606 9,767 0.02% 0.02% 35 -7,463 -2.11% Q1 2026 May 14, 2026
Invesco Ltd. History Reduced 343,176 9,677 0.0% 0.01% 36 -929,046 -73.03% Q1 2026 May 12, 2026
Front Street Capital Management, Inc. History Reduced 261,088 7,363 0.98% 1.12% 37 -25,906 -9.03% Q1 2026 May 21, 2026
Vanguard Global Advisers, LLC History New 258,998 7,300 0.0% 38 +258,998 New Q1 2026 May 08, 2026
Van Berkom & Associates Inc. History Reduced 257,360 7,239 0.24% 0.21% 39 -11,776 -4.38% Q1 2026 May 07, 2026
FRANKLIN RESOURCES INC History Added to 247,467 6,976 0.0% 0.0% 40 +222,081 874.82% Q1 2026 May 13, 2026
CHARLES SCHWAB INVESTMENT MANAGEMENT INC History Added to 238,654 6,705 0.0% 0.0% 41 +2,322 0.98% Q1 2026 May 15, 2026
UBS Group AG History Reduced 227,628 6,419 0.0% 0.0% 42 -1,146 -0.5% Q1 2026 May 05, 2026
Waratah Capital Advisors Ltd. History New 223,983 6,316 0.24% 43 +223,983 New Q1 2026 May 11, 2026
Dixon Mitchell Investment Counsel Inc. History No change 211,025 5,929 0.21% 0.19% 44 0 0.0% Q1 2026 May 14, 2026
SCOTIA CAPITAL INC. History Reduced 192,530 5,379 0.02% 0.02% 45 -2,489 -1.28% Q1 2026 May 13, 2026
Focus Partners Wealth History No change 181,975 5,131 0.01% 0.01% 46 0 0.0% Q1 2026 May 14, 2026
ROYCE & ASSOCIATES LP History Added to 179,500 5,059 0.05% 0.05% 47 +15,000 9.12% Q1 2026 May 12, 2026
ArrowMark Colorado Holdings LLC History New 174,000 4,906 0.13% 48 +174,000 New Q1 2026 May 15, 2026
Granite Investment Partners, LLC History Reduced 173,031 4,879 0.3% 0.33% 49 -30,845 -15.13% Q1 2026 Apr 30, 2026
MONTRUSCO BOLTON INVESTMENTS INC. History Reduced 170,956 4,803 0.07% 0.09% 50 -83,725 -32.87% Q1 2026 Apr 28, 2026
SEI INVESTMENTS CO History Added to 167,820 4,732 0.0% 0.0% 51 +69,078 69.96% Q1 2026 May 13, 2026
Swiss National Bank History No change 164,400 4,627 0.0% 0.0% 52 0 0.0% Q1 2026 May 07, 2026
FIRST TRUST ADVISORS LP History Reduced 154,403 4,352 0.0% 0.0% 53 -29,725 -16.14% Q1 2026 May 13, 2026
Candelo Capital Management LP History Added to 151,688 4,274 3.53% 0.61% 54 +126,988 514.12% Q1 2026 May 15, 2026
CIBC Asset Management Inc History Added to 134,186 3,770 0.01% 0.01% 55 +2,686 2.04% Q1 2026 May 12, 2026
DIMENSIONAL FUND ADVISORS LP History Added to 122,456 3,451 0.0% 0.0% 56 +12,114 10.98% Q1 2026 May 07, 2026
Federation des caisses Desjardins du Quebec History Reduced 113,047 3,158 0.01% 0.01% 57 -3,357 -2.88% Q1 2026 May 13, 2026
HARBOR CAPITAL ADVISORS, INC. History New 103,168 2,909 0.24% 58 +103,168 New Q1 2026 Apr 28, 2026
MORGAN STANLEY History Added to 100,390 2,831 0.0% 0.0% 59 +78,899 367.13% Q1 2026 May 15, 2026
TORONTO DOMINION BANK History Added to 93,175 2,627 0.0% 0.0% 60 +11,265 13.75% Q1 2026 May 15, 2026
Canoe Financial LP History Added to 87,430 2,463 0.03% 0.03% 61 +6,830 8.47% Q1 2026 Apr 22, 2026
LOUISBOURG INVESTMENTS INC. History Reduced 84,855 2,386 0.45% 1.14% 62 -122,275 -59.03% Q1 2026 Apr 22, 2026
JANE STREET GROUP, LLC History Added to 82,641 2,328 0.0% 0.0% 63 +60,578 274.57% Q1 2026 May 12, 2026
CITADEL ADVISORS LLC History Reduced 81,239 2,290 0.0% 0.0% 64 -67,601 -45.42% Q1 2026 May 15, 2026
MANUFACTURERS LIFE INSURANCE COMPANY, THE History Reduced 74,130 2,087 0.0% 0.0% 65 -2,296 -3.0% Q1 2026 May 15, 2026
BRITISH COLUMBIA INVESTMENT MANAGEMENT Corp History Added to 70,422 1,985 0.01% 0.01% 66 +26,669 60.95% Q1 2026 May 13, 2026
GEODE CAPITAL MANAGEMENT, LLC History Added to 68,798 1,972 0.0% 0.0% 67 +9,543 16.1% Q1 2026 May 15, 2026
LAZARD ASSET MANAGEMENT LLC History Added to 69,912 1,971 0.0% 0.0% 68 +11,486 19.66% Q1 2026 May 15, 2026
SIG North Trading, ULC History Added to 69,675 1,964 0.04% 0.03% 69 +14,033 25.22% Q1 2026 May 15, 2026
VANGUARD ASSET MANAGEMENT, Ltd History New 66,830 1,883 0.0% 70 +66,830 New Q1 2026 May 08, 2026
Nuveen, LLC History No change 62,584 1,758 0.0% 0.0% 71 0 0.0% Q1 2026 Apr 30, 2026
Caldwell Investment Management Ltd. History No change 60,800 1,648 0.65% 1.04% 72 0 0.0% Q1 2026 May 14, 2026
INTACT INVESTMENT MANAGEMENT INC. History New 53,389 1,504 0.04% 73 +53,389 New Q1 2026 May 08, 2026
GOLDMAN SACHS GROUP INC History Reduced 52,251 1,473 0.0% 0.0% 74 -233,126 -81.69% Q1 2026 May 15, 2026
PCJ Investment Counsel Ltd. History New 50,000 1,409 0.4% 75 +50,000 New Q1 2026 May 11, 2026
GUARDIAN CAPITAL LP History Reduced 46,955 1,319 0.03% 0.04% 76 -108 -0.23% Q1 2026 May 15, 2026
Aviso Financial Inc. History Reduced 45,760 1,288 0.05% 0.05% 77 -5,965 -11.53% Q1 2026 May 13, 2026
BANK OF NOVA SCOTIA TRUST CO History Added to 34,332 968 0.08% 0.07% 78 +3,818 12.51% Q1 2026 May 13, 2026
Zurcher Kantonalbank (Zurich Cantonalbank) History Reduced 31,450 883 0.0% 0.0% 79 -33,189 -51.35% Q1 2026 May 15, 2026
D. E. Shaw & Co., Inc. History Reduced 30,200 850 0.0% 0.0% 80 -77,900 -72.06% Q1 2026 May 15, 2026
Purpose Unlimited Inc. History Reduced 28,567 805 0.03% 0.04% 81 -235 -0.82% Q1 2026 May 15, 2026
Numerai GP LLC History Added to 27,538 776 0.08% 0.05% 82 +11,233 68.89% Q1 2026 May 15, 2026
PUBLIC EMPLOYEES RETIREMENT SYSTEM OF OHIO History Added to 27,335 767 0.0% 0.0% 83 +120 0.44% Q1 2026 May 14, 2026
CITIGROUP INC History Added to 26,816 753 0.0% 0.0% 84 +1,667 6.63% Q1 2026 May 11, 2026
Aberdeen Group plc History Added to 26,237 739 0.0% 0.0% 85 +6,230 31.14% Q1 2026 Apr 29, 2026
VAN ECK ASSOCIATES CORP History Added to 24,271 684 0.0% 0.0% 86 +10,700 78.84% Q1 2026 May 15, 2026
ExodusPoint Capital Management, LP History New 22,050 621 0.01% 87 +22,050 New Q1 2026 May 14, 2026
PenderFund Capital Management Ltd. History No change 20,000 563 0.09% 0.09% 88 0 0.0% Q1 2026 May 15, 2026
Vanguard Investments Australia, Ltd. History New 19,315 544 0.0% 89 +19,315 New Q1 2026 May 08, 2026
Pictet Asset Management Holding SA History Added to 16,423 461 0.0% 0.0% 90 +417 2.61% Q1 2026 Apr 22, 2026
Mariner, LLC History Added to 16,237 457 0.0% 0.0% 91 +4,070 33.45% Q1 2026 May 13, 2026
BALYASNY ASSET MANAGEMENT L.P. History New 14,124 398 0.0% 92 +14,124 New Q1 2026 May 15, 2026
Engineers Gate Manager LP History New 13,052 367 0.0% 93 +13,052 New Q1 2026 May 15, 2026
Savant Capital, LLC History Added to 12,657 356 0.0% 0.0% 94 +1,285 11.3% Q1 2026 May 04, 2026
TRUE Private Wealth Advisors History No change 12,080 340 0.03% 0.03% 95 0 0.0% Q1 2026 May 15, 2026
STIFEL FINANCIAL CORP History Reduced 11,891 335 0.0% 0.0% 96 -702 -5.57% Q1 2026 May 12, 2026
Investment Management Corp of Ontario History Added to 11,716 330 0.0% 0.0% 97 +1,600 15.82% Q1 2026 May 15, 2026
Northwest & Ethical Investments L.P. History Added to 10,983 309 0.01% 0.01% 99 +430 4.07% Q1 2026 May 13, 2026
SkyView Investment Advisors, LLC History No change 10,966 309 0.04% 0.04% 98 0 0.0% Q1 2026 May 14, 2026
DEUTSCHE BANK AG\ History Added to 10,752 303 0.0% 0.0% 100 +491 4.79% Q1 2026 May 06, 2026
MARSHALL WACE, LLP History New 9,920 279 0.0% 101 +9,920 New Q1 2026 May 14, 2026
ALLIANCEBERNSTEIN L.P. History No change 8,960 246 0.0% 0.0% 102 0 0.0% Q1 2026 May 15, 2026
Brevan Howard Capital Management LP History New 8,424 237 0.0% 104 +8,424 New Q1 2026 May 15, 2026
Campbell & CO Investment Adviser LLC History Reduced 8,427 237 0.01% 0.01% 103 -378 -4.29% Q1 2026 May 15, 2026
Orion Porfolio Solutions, LLC History New 7,994 225 0.0% 105 +7,994 New Q1 2026 May 13, 2026
Tower Research Capital LLC (TRC) History New 7,900 222 0.01% 106 +7,900 New Q1 2026 May 15, 2026
Gotham Asset Management, LLC History New 7,671 216 0.0% 107 +7,671 New Q1 2026 May 15, 2026
ACADIAN ASSET MANAGEMENT LLC History New 5,400 151 0.0% 108 +5,400 New Q1 2026 May 13, 2026
BARCLAYS PLC History Reduced 2,978 83 0.0% 0.0% 109 -2,286 -43.43% Q1 2026 May 14, 2026
Russell Investments Group, Ltd. History Reduced 2,828 79 0.0% 0.0% 110 -5,701 -66.84% Q1 2026 May 08, 2026
HANTZ FINANCIAL SERVICES, INC. History Added to 2,717 77 0.0% 0.0% 111 +2,544 1470.52% Q1 2026 May 01, 2026
WELLS FARGO & COMPANY/MN History Added to 1,507 42 0.0% 0.0% 112 +796 111.95% Q1 2026 May 11, 2026
State of Wyoming History New 1,215 34 0.0% 113 +1,215 New Q1 2026 May 13, 2026
Smartleaf Asset Management LLC History No change 1,052 28 0.0% 0.0% 114 0 0.0% Q1 2026 May 15, 2026
JPMORGAN CHASE & CO History Added to 963 26 0.0% 0.0% 115 +410 74.14% Q1 2026 May 13, 2026
Blue Trust, Inc. History No change 733 20 0.0% 0.0% 116 0 0.0% Q1 2026 Apr 20, 2026
Hillsdale Investment Management Inc. History No change 600 16 0.0% 0.0% 117 0 0.0% Q1 2026 May 04, 2026
OSAIC HOLDINGS, INC. History Added to 354 9 0.0% 118 +324 1080.0% Q1 2026 May 15, 2026
Farther Finance Advisors, LLC History No change 263 7 0.0% 0.0% 119 0 0.0% Q1 2026 Apr 07, 2026
Western Wealth Management, LLC History New 236 6 0.0% 120 +236 New Q1 2026 May 19, 2026
Larson Financial Group LLC History Added to 198 5 0.0% 0.0% 121 +77 63.64% Q1 2026 May 15, 2026
Bank of Jackson Hole Trust History Reduced 113 3 0.0% 0.0% 122 -24 -17.52% Q1 2026 May 12, 2026
WealthCollab, LLC History No change 89 2 0.0% 0.0% 123 0 0.0% Q1 2026 May 13, 2026
EverSource Wealth Advisors, LLC History Reduced 56 1 0.0% 0.0% 125 -13 -18.84% Q1 2026 May 15, 2026
JONES FINANCIAL COMPANIES LLLP History No change 36 1 0.0% 124 0 0.0% Q1 2026 May 15, 2026
Root Financial Partners, LLC History No change 40 1 0.0% 0.0% 126 0 0.0% Q1 2026 Apr 24, 2026
BlackRock, Inc. History No change 58 1 0.0% 0.0% 127 0 0.0% Q1 2026 May 13, 2026
HEALTHCARE OF ONTARIO PENSION PLAN TRUST FUND History Closed out 0 0 0.03% -753,492 -100.0% Q1 2026 May 14, 2026
AGF MANAGEMENT LTD History Closed out 0 0 0.05% -400,140 -100.0% Q1 2026 May 07, 2026
Polar Asset Management Partners Inc. History Closed out 0 0 0.06% -180,000 -100.0% Q1 2026 May 15, 2026
MILLENNIUM MANAGEMENT LLC History Closed out 0 0 0.0% -75,879 -100.0% Q1 2026 May 15, 2026
AYAL Capital Advisors Ltd History Closed out 0 0 0.69% -72,200 -100.0% Q1 2026 May 15, 2026
Fiera Capital Corp History Closed out 0 0 0.01% -71,007 -100.0% Q1 2026 May 12, 2026
Main Management ETF Advisors, LLC History Closed out 0 0 0.03% -29,754 -100.0% Q1 2026 May 14, 2026
Third View Private Wealth, LLC History Closed out 0 0 0.05% -12,264 -100.0% Q1 2026 Apr 15, 2026
XTX Topco Ltd History Closed out 0 0 0.01% -10,640 -100.0% Q1 2026 May 15, 2026
Rockefeller Capital Management L.P. History Closed out 0 0 0.0% -9,790 -100.0% Q1 2026 May 14, 2026
Verition Fund Management LLC History Closed out 0 0 0.0% -9,192 -100.0% Q1 2026 May 15, 2026
ENVESTNET ASSET MANAGEMENT INC History Closed out 0 0 0.0% -7,634 -100.0% Q1 2026 May 04, 2026
WOLVERINE ASSET MANAGEMENT LLC History Closed out 0 0 0.0% -3,000 -100.0% Q1 2026 May 04, 2026
Banque Cantonale Vaudoise History Closed out 0 0 0.0% -261 -100.0% Q1 2026 Apr 20, 2026
Pacer Advisors, Inc. History Closed out 0 0 0.0% -137 -100.0% Q1 2026 May 06, 2026
Caitong International Asset Management Co., Ltd History New 17 0 +17 New Q1 2026 May 11, 2026
Leonteq Securities AG History No change 4 0 0 0.0% Q1 2026 Apr 27, 2026
Bell Investment Advisors, Inc History No change 20 0 0 0.0% Q1 2026 Apr 17, 2026