ATS Corp /ATS - ATS

Detailed investor-level table based on 13F positions.

Shareholders (13F)

Quarter: Q4 2025 · Compare: Q3 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 No change 15,563,568 428,620 76.32% 82.99% 1 0 0.0% Q4 2025 Feb 17, 2026
ROYAL BANK OF CANADA History New 7,644,547 210,529 0.03% 2 +7,644,547 New Q4 2025 Feb 17, 2026
EdgePoint Investment Group Inc. History Added to 6,888,785 189,771 1.56% 1.25% 3 +507,491 7.95% Q4 2025 Feb 17, 2026
Beutel, Goodman & Co Ltd. History Reduced 5,837,138 161,008 0.99% 1.0% 4 -493,550 -7.8% Q4 2025 Feb 13, 2026
Turtle Creek Asset Management Inc. History Reduced 5,642,052 155,382 6.84% 5.51% 5 -1,330,958 -19.09% Q4 2025 Feb 13, 2026
VANGUARD GROUP INC History Added to 3,397,166 93,581 0.0% 0.0% 6 +55,731 1.67% Q4 2025 Jan 29, 2026
BANK OF MONTREAL /CAN/ History Added to 3,022,693 83,268 0.03% 0.01% 7 +1,790,040 145.22% Q4 2025 Feb 12, 2026
Connor, Clark & Lunn Investment Management Ltd. History Added to 2,485,638 68,473 0.18% 0.17% 8 +432,166 21.05% Q4 2025 Feb 10, 2026
FAIRFAX FINANCIAL HOLDINGS LTD/ CAN History No change 2,486,400 68,282 3.28% 3.11% 9 0 0.0% Q4 2025 Feb 17, 2026
FMR LLC History Added to 2,117,766 58,338 0.0% 0.0% 10 +742,179 53.95% Q4 2025 Feb 17, 2026
ACK Asset Management LLC History No change 1,846,196 50,844 6.38% 6.05% 11 0 0.0% Q4 2025 Feb 13, 2026
Hill City Capital, LP History No change 1,649,857 45,437 1.72% 1.83% 12 0 0.0% Q4 2025 Feb 13, 2026
Alberta Investment Management Corp History No change 1,340,265 36,918 0.22% 0.25% 13 0 0.0% Q4 2025 Feb 19, 2026
Invesco Ltd. History Added to 1,272,222 35,036 0.01% 0.0% 14 +75,490 6.31% Q4 2025 Feb 19, 2026
Scheer, Rowlett & Associates Investment Management Ltd. History Added to 1,226,450 33,786 2.32% 1.9% 15 +9,266 0.76% Q4 2025 Feb 10, 2026
TD ASSET MANAGEMENT INC History Added to 1,193,208 32,912 0.03% 0.03% 16 +11,446 0.97% Q4 2025 Feb 10, 2026
MIRAE ASSET GLOBAL ETFS HOLDINGS Ltd. History Added to 1,141,835 31,495 0.05% 0.05% 17 +32,605 2.94% Q4 2025 Feb 17, 2026
VAN LANSCHOT KEMPEN INVESTMENT MANAGEMENT N.V. History Reduced 815,031 30,816 0.26% 0.27% 18 -647 -0.08% Q4 2025 Feb 13, 2026
Clearbridge Investments, LLC History Reduced 1,111,485 30,610 0.02% 0.02% 19 -18,896 -1.67% Q4 2025 Feb 11, 2026
BANK OF AMERICA CORP /DE/ History Reduced 1,100,381 30,304 0.0% 0.0% 20 -151,314 -12.09% Q4 2025 Feb 17, 2026
Marathon Asset Management Ltd History Reduced 1,097,711 30,277 1.16% 1.12% 21 -68,296 -5.86% Q4 2025 Feb 06, 2026
NORGES BANK History New 1,079,090 29,726 0.0% 22 +1,079,090 New Q4 2025 Feb 10, 2026
TD Waterhouse Canada Inc. History Reduced 966,349 26,496 0.16% 0.24% 23 -463,883 -32.43% Q4 2025 Jan 27, 2026
PRINCIPAL FINANCIAL GROUP INC History Added to 878,240 24,224 0.01% 0.01% 24 +4,100 0.47% Q4 2025 Feb 02, 2026
JANUS HENDERSON GROUP PLC History Reduced 861,839 23,772 0.01% 0.01% 25 -36,504 -4.06% Q4 2025 Feb 17, 2026
1832 Asset Management L.P. History Added to 818,559 22,543 0.02% 0.02% 26 +79,828 10.81% Q4 2025 Feb 13, 2026
MACKENZIE FINANCIAL CORP History Reduced 758,980 21,053 0.02% 0.04% 27 -379,579 -33.34% Q4 2025 Feb 18, 2026
HEALTHCARE OF ONTARIO PENSION PLAN TRUST FUND History No change 753,492 20,758 0.03% 0.04% 28 0 0.0% Q4 2025 Feb 13, 2026
MASSACHUSETTS FINANCIAL SERVICES CO /MA/ History Reduced 558,675 15,385 0.0% 0.0% 29 -10,999 -1.93% Q4 2025 Jan 22, 2026
Legal & General Group Plc History Added to 542,023 14,930 0.0% 0.0% 30 +47,414 9.59% Q4 2025 Feb 09, 2026
NATIONAL BANK OF CANADA /FI/ History Reduced 418,332 11,468 0.01% 0.01% 31 -1,693 -0.4% Q4 2025 Feb 17, 2026
AGF MANAGEMENT LTD History Reduced 400,140 11,022 0.05% 0.06% 32 -89,816 -18.33% Q4 2025 Feb 17, 2026
CIBC WORLD MARKET INC. History Reduced 354,069 9,754 0.02% 0.02% 33 -15,444 -4.18% Q4 2025 Feb 10, 2026
PUBLIC SECTOR PENSION INVESTMENT BOARD History Added to 287,829 7,929 0.03% 0.01% 34 +225,923 364.95% Q4 2025 Feb 13, 2026
Front Street Capital Management, Inc. History Reduced 286,994 7,904 1.12% 1.17% 35 -2,778 -0.96% Q4 2025 Feb 18, 2026
GOLDMAN SACHS GROUP INC History Reduced 285,377 7,859 0.0% 0.0% 36 -222,508 -43.81% Q4 2025 Mar 25, 2026
Van Berkom & Associates Inc. History Reduced 269,136 7,425 0.21% 0.2% 37 -858 -0.32% Q4 2025 Feb 02, 2026
MONTRUSCO BOLTON INVESTMENTS INC. History Reduced 254,681 7,024 0.09% 0.09% 38 -29,100 -10.25% Q4 2025 Jan 29, 2026
CHARLES SCHWAB INVESTMENT MANAGEMENT INC History Added to 236,332 6,518 0.0% 0.0% 39 +5,826 2.53% Q4 2025 Feb 13, 2026
UBS Group AG History Reduced 228,774 6,300 0.0% 0.0% 40 -2,821 -1.22% Q4 2025 Jan 29, 2026
Dixon Mitchell Investment Counsel Inc. History Reduced 211,025 5,820 0.19% 0.2% 41 -7,500 -3.43% Q4 2025 Feb 13, 2026
LOUISBOURG INVESTMENTS INC. History Reduced 207,130 5,713 1.14% 1.23% 42 -8,165 -3.79% Q4 2025 Jan 16, 2026
Granite Investment Partners, LLC History Reduced 203,876 5,614 0.33% 0.31% 43 -1,971 -0.96% Q4 2025 Feb 12, 2026
SCOTIA CAPITAL INC. History Reduced 195,019 5,346 0.02% 0.02% 44 -13,999 -6.7% Q4 2025 Feb 12, 2026
FIRST TRUST ADVISORS LP History Added to 184,128 5,072 0.0% 0.0% 45 +35,416 23.82% Q4 2025 Feb 13, 2026
Focus Partners Wealth History Reduced 181,975 5,011 0.01% 0.01% 46 -13 -0.01% Q4 2025 Feb 13, 2026
Polar Asset Management Partners Inc. History New 180,000 4,959 0.06% 47 +180,000 New Q4 2025 Feb 17, 2026
Swiss National Bank History Added to 164,400 4,538 0.0% 0.0% 48 +4,300 2.69% Q4 2025 Feb 12, 2026
ROYCE & ASSOCIATES LP History Added to 164,500 4,531 0.05% 0.04% 49 +30,000 22.3% Q4 2025 Feb 09, 2026
CITADEL ADVISORS LLC History Added to 148,840 4,099 0.0% 0.0% 50 +64,520 76.52% Q4 2025 Feb 17, 2026
CIBC Asset Management Inc History Reduced 131,500 3,624 0.01% 0.01% 51 -3,354 -2.49% Q4 2025 Feb 10, 2026
Federation des caisses Desjardins du Quebec History Reduced 116,404 3,198 0.01% 0.02% 52 -78,830 -40.38% Q4 2025 Feb 12, 2026
DIMENSIONAL FUND ADVISORS LP History Added to 110,342 3,039 0.0% 0.0% 53 +21,119 23.67% Q4 2025 Feb 12, 2026
D. E. Shaw & Co., Inc. History Reduced 108,100 2,978 0.0% 0.0% 54 -109,800 -50.39% Q4 2025 Feb 17, 2026
SEI INVESTMENTS CO History New 98,742 2,719 0.0% 55 +98,742 New Q4 2025 Feb 13, 2026
TORONTO DOMINION BANK History Reduced 81,910 2,257 0.0% 0.0% 56 -545 -0.66% Q4 2025 Feb 17, 2026
Canoe Financial LP History Added to 80,600 2,220 0.03% 0.03% 57 +1,723 2.18% Q4 2025 Jan 14, 2026
MANUFACTURERS LIFE INSURANCE COMPANY, THE History New 76,426 2,109 0.0% 58 +76,426 New Q4 2025 Feb 13, 2026
MILLENNIUM MANAGEMENT LLC History Added to 75,879 2,089 0.0% 0.0% 59 +32,058 73.16% Q4 2025 Feb 17, 2026
AYAL Capital Advisors Ltd History New 72,200 1,988 0.69% 60 +72,200 New Q4 2025 Feb 17, 2026
Fiera Capital Corp History Reduced 71,007 1,956 0.01% 0.01% 61 -22,152 -23.78% Q4 2025 Feb 11, 2026
Zurcher Kantonalbank (Zurich Cantonalbank) History Reduced 64,639 1,782 0.0% 0.01% 62 -26,972 -29.44% Q4 2025 Jan 27, 2026
Nuveen, LLC History No change 62,584 1,726 0.0% 0.0% 63 0 0.0% Q4 2025 Feb 12, 2026
Caldwell Investment Management Ltd. History No change 60,800 1,688 1.04% 1.05% 64 0 0.0% Q4 2025 Feb 11, 2026
GEODE CAPITAL MANAGEMENT, LLC History Added to 59,255 1,665 0.0% 0.0% 65 +9,023 17.96% Q4 2025 Feb 09, 2026
LAZARD ASSET MANAGEMENT LLC History New 58,426 1,609 0.0% 66 +58,426 New Q4 2025 Feb 17, 2026
SIG North Trading, ULC History Added to 55,642 1,532 0.03% 0.02% 67 +19,642 54.56% Q4 2025 Feb 17, 2026
FIL Ltd History New 53,569 1,474 0.0% 68 +53,569 New Q4 2025 Feb 17, 2026
Aviso Financial Inc. History Reduced 51,725 1,424 0.05% 0.06% 69 -518 -0.99% Q4 2025 Feb 13, 2026
GUARDIAN CAPITAL LP History New 47,063 1,298 0.04% 70 +47,063 New Q4 2025 Feb 18, 2026
BRITISH COLUMBIA INVESTMENT MANAGEMENT Corp History Reduced 43,753 1,205 0.01% 0.01% 71 -4,053 -8.48% Q4 2025 Feb 13, 2026
BANK OF NOVA SCOTIA TRUST CO History Added to 30,514 840 0.07% 0.06% 72 +5,439 21.69% Q4 2025 Feb 12, 2026
Main Management ETF Advisors, LLC History Added to 29,754 819 0.03% 0.03% 73 +304 1.03% Q4 2025 Feb 10, 2026
Purpose Unlimited Inc. History New 28,802 793 0.04% 74 +28,802 New Q4 2025 Mar 20, 2026
PUBLIC EMPLOYEES RETIREMENT SYSTEM OF OHIO History Added to 27,215 750 0.0% 0.0% 75 +10 0.04% Q4 2025 Feb 17, 2026
FRANKLIN RESOURCES INC History Added to 25,386 699 0.0% 0.0% 76 +9,556 60.37% Q4 2025 Feb 11, 2026
CITIGROUP INC History Added to 25,149 693 0.0% 0.0% 77 +8,707 52.96% Q4 2025 Feb 13, 2026
Candelo Capital Management LP History New 24,700 680 0.61% 78 +24,700 New Q4 2025 Feb 17, 2026
JANE STREET GROUP, LLC History New 22,063 607 0.0% 79 +22,063 New Q4 2025 Feb 12, 2026
MORGAN STANLEY History Reduced 21,491 591 0.0% 0.0% 80 -48,148 -69.14% Q4 2025 Feb 13, 2026
Aberdeen Group plc History Added to 20,007 550 0.0% 0.0% 82 +1,412 7.59% Q4 2025 Jan 16, 2026
PenderFund Capital Management Ltd. History No change 20,000 550 0.09% 0.09% 81 0 0.0% Q4 2025 Feb 17, 2026
Numerai GP LLC History New 16,305 449 0.05% 83 +16,305 New Q4 2025 Feb 17, 2026
Pictet Asset Management Holding SA History Added to 16,006 441 0.0% 0.0% 84 +468 3.01% Q4 2025 Jan 29, 2026
VAN ECK ASSOCIATES CORP History Added to 13,571 374 0.0% 0.0% 85 +7,559 125.73% Q4 2025 Feb 13, 2026
STIFEL FINANCIAL CORP History Added to 12,593 346 0.0% 0.0% 86 +467 3.85% Q4 2025 Feb 13, 2026
Third View Private Wealth, LLC History New 12,264 337 0.05% 87 +12,264 New Q4 2025 Jan 23, 2026
Mariner, LLC History Added to 12,167 335 0.0% 0.0% 88 +3,143 34.83% Q4 2025 Feb 13, 2026
TRUE Private Wealth Advisors History No change 12,080 332 0.03% 0.03% 89 0 0.0% Q4 2025 Feb 13, 2026
Savant Capital, LLC History New 11,372 313 0.0% 90 +11,372 New Q4 2025 Feb 10, 2026
SkyView Investment Advisors, LLC History New 10,966 302 0.04% 91 +10,966 New Q4 2025 Feb 18, 2026
XTX Topco Ltd History Reduced 10,640 293 0.01% 0.02% 92 -2,981 -21.89% Q4 2025 Feb 17, 2026
Northwest & Ethical Investments L.P. History Added to 10,553 290 0.01% 0.01% 93 +1,940 22.52% Q4 2025 Feb 17, 2026
DEUTSCHE BANK AG\ History Reduced 10,261 282 0.0% 0.0% 94 -627 -5.76% Q4 2025 Feb 11, 2026
Investment Management Corp of Ontario History New 10,116 278 0.0% 95 +10,116 New Q4 2025 Feb 17, 2026
Rockefeller Capital Management L.P. History Reduced 9,790 270 0.0% 0.0% 96 -18,941 -65.93% Q4 2025 Mar 16, 2026
Verition Fund Management LLC History New 9,192 253 0.0% 97 +9,192 New Q4 2025 Feb 13, 2026
ALLIANCEBERNSTEIN L.P. History Reduced 8,960 246 0.0% 0.0% 98 -860 -8.76% Q4 2025 Feb 17, 2026
Campbell & CO Investment Adviser LLC History New 8,805 242 0.01% 99 +8,805 New Q4 2025 Feb 12, 2026
Russell Investments Group, Ltd. History Reduced 8,529 235 0.0% 0.0% 100 -24,556 -74.22% Q4 2025 Feb 17, 2026
ENVESTNET ASSET MANAGEMENT INC History Reduced 7,634 210 0.0% 0.0% 101 -10,160 -57.1% Q4 2025 Feb 10, 2026
BARCLAYS PLC History Added to 5,264 144 0.0% 0.0% 102 +756 16.77% Q4 2025 Feb 13, 2026
WOLVERINE ASSET MANAGEMENT LLC History Reduced 3,000 82 0.0% 0.0% 103 -300 -9.09% Q4 2025 Feb 02, 2026
Smartleaf Asset Management LLC History New 1,052 29 0.0% 104 +1,052 New Q4 2025 Feb 13, 2026
Blue Trust, Inc. History New 733 20 0.0% 105 +733 New Q4 2025 Jan 16, 2026
WELLS FARGO & COMPANY/MN History Added to 711 19 0.0% 0.0% 106 +79 12.5% Q4 2025 Feb 13, 2026
Hillsdale Investment Management Inc. History New 600 16 0.0% 107 +600 New Q4 2025 Feb 10, 2026
JPMORGAN CHASE & CO History Reduced 553 15 0.0% 0.0% 108 -161 -22.55% Q4 2025 Feb 11, 2026
Banque Cantonale Vaudoise History Reduced 261 7 0.0% 0.0% 109 -99 -27.5% Q4 2025 Feb 06, 2026
Farther Finance Advisors, LLC History Added to 263 7 0.0% 0.0% 110 +20 8.23% Q4 2025 Jan 23, 2026
HANTZ FINANCIAL SERVICES, INC. History No change 173 5 0.0% 0.0% 111 0 0.0% Q4 2025 Feb 09, 2026
Bank of Jackson Hole Trust History New 137 3 0.0% 114 +137 New Q4 2025 Feb 12, 2026
Larson Financial Group LLC History Added to 121 3 0.0% 113 +108 830.77% Q4 2025 Feb 06, 2026
Pacer Advisors, Inc. History Added to 137 3 0.0% 0.0% 112 +38 38.38% Q4 2025 Feb 24, 2026
WealthCollab, LLC History No change 89 2 0.0% 0.0% 115 0 0.0% Q4 2025 Jan 27, 2026
BlackRock, Inc. History New 58 1 0.0% 118 +58 New Q4 2025 Feb 12, 2026
EverSource Wealth Advisors, LLC History Added to 69 1 0.0% 116 +49 245.0% Q4 2025 Feb 06, 2026
Root Financial Partners, LLC History No change 40 1 0.0% 0.0% 117 0 0.0% Q4 2025 Feb 10, 2026
Foresight Group Ltd Liability Partnership History Closed out 0 0 1.52% -388,892 -100.0% Q3 2025 Nov 06, 2025
Roubaix Capital, LLC History Closed out 0 0 2.73% -223,532 -100.0% Q3 2025 Nov 12, 2025
Bastion Asset Management Inc. History Closed out 0 0 1.1% -72,655 -100.0% Q3 2025 Nov 07, 2025
Blackstone Inc. History Closed out 0 0 0.01% -49,501 -100.0% Q3 2025 Nov 14, 2025
Amundi History Closed out 0 0 0.0% -27,180 -100.0% Q3 2025 Nov 14, 2025
Lombard Odier Asset Management (Switzerland) SA History Closed out 0 0 0.03% -21,515 -100.0% Q3 2025 Nov 14, 2025
BOOTHBAY FUND MANAGEMENT, LLC History Closed out 0 0 0.0% -10,170 -100.0% Q3 2025 Nov 14, 2025
Quantbot Technologies LP History Closed out 0 0 0.0% -4,665 -100.0% Q3 2025 Nov 12, 2025
State of Wyoming History Closed out 0 0 0.01% -4,262 -100.0% Q3 2025 Nov 04, 2025
Quarry LP History Closed out 0 0 0.01% -1,238 -100.0% Q3 2025 Nov 14, 2025
Tower Research Capital LLC (TRC) History Closed out 0 0 0.0% -1,000 -100.0% Q3 2025 Nov 14, 2025
OSAIC HOLDINGS, INC. History Reduced 30 0 0.0% -591 -95.17% Q4 2025 Feb 17, 2026
Caitong International Asset Management Co., Ltd History Closed out 0 0 0.0% -143 -100.0% Q3 2025 Nov 19, 2025
SIMPLEX TRADING, LLC History Closed out 0 0 0.0% -67 -100.0% Q3 2025 Nov 12, 2025
JONES FINANCIAL COMPANIES LLLP History Reduced 36 0 0.0% -13 -26.53% Q4 2025 Feb 17, 2026
Leonteq Securities AG History No change 4 0 0 0.0% Q4 2025 Feb 06, 2026
Bell Investment Advisors, Inc History No change 20 0 0 0.0% Q4 2025 Feb 24, 2026