AtsATS
13F holders, Q3 2025 (September 30)At the end of Q3 2025, 115 institutions reported holding Ats Corp. (ATS) in their 13F filings, down 16 from Q2 2025. 15 opened new positions and 29 sold out. The largest holders were Mason Capital Management LLC ($407.8M), Royal Bank of Canada ($188.7M) and Turtle Creek Asset Management Inc. ($182.7M). 4 famous investors held it, including Prem Watsa (3.1% of Fairfax Financial Holdings's portfolio), David E. Shaw (0.0% of D. E. Shaw & Co.'s portfolio) and Ken Griffin (0.0% of Citadel Advisors's portfolio).
- Company
- Ats Corp.
- CUSIP
- 00217Y104
- Latest filing quarter
- Q2 2026
History
Number of 13F holders
Total Exit/New Position Q2 2025 → Q3 2025
| Institutions | Total Value | |
|---|---|---|
| New Positions | 15 | $18.2M |
| Exits | 29 | $87.7M |
All 13F filers, Q2 2025 → Q3 2025: 4,154,295 shares bought and 6,388,913 shares sold, net −2,234,618 shares. Counts holders who added, trimmed, opened or closed a position; split-adjusted.
Ownership 115 holders
| Mason Capital Management LLC | 82.99% | No change | 15,563,568 | $407.8M |
| Royal Bank of Canada | 0.03% | Add +1.8% | 7,201,778 | $188.7M |
| Turtle Creek Asset Management Inc. | 5.51% | Reduce -8.1% | 6,973,010 | $182.7M |
| EdgePoint Investment Group Inc. | 1.25% | Reduce -0.8% | 6,381,294 | $166.9M |
| Beutel, Goodman & Co Ltd. | 1.00% | Reduce -7.4% | 6,330,688 | $165.7M |
| Vanguard Group Inc. | 0.00% | Add +2.1% | 3,341,435 | $87.4M |
| Fairfax Financial Holdings | 3.11% | No change | 2,486,400 | $64.1M |
| Connor, Clark & Lunn Investment Management Ltd. | 0.17% | Reduce -13.3% | 2,053,472 | $53.7M |
| Burgundy Asset Management Ltd. | 0.47% | Reduce -0.3% | 1,807,557 | $50.0M |
| ACK Asset Management LLC | 6.05% | No change | 1,846,196 | $48.4M |
| Hill City Capital, LP | 1.83% | Add +34.7% | 1,649,857 | $43.2M |
| TD Waterhouse Canada Inc. | 0.24% | Reduce -1.5% | 1,430,232 | $37.4M |
| FMR LLC | 0.00% | Reduce -2.1% | 1,375,587 | $36.0M |
| Alberta Investment Management Corp | 0.28% | Add +74.6% | 1,340,265 | $35.1M |
| Bank of America Corp. | 0.00% | Add +45.2% | 1,251,695 | $32.8M |
| Scheer, Rowlett & Associates Investment Management Ltd. | 1.90% | Add +53.6% | 1,217,184 | $31.8M |
| Invesco Ltd. | 0.01% | Add +0.7% | 1,196,732 | $31.4M |
| TD Asset Management Inc | 0.03% | Reduce -7.6% | 1,181,762 | $30.9M |
| Marathon Asset Management Ltd | 1.12% | Reduce -5.6% | 1,166,007 | $30.5M |
| Bank of Montreal | 0.01% | Add +4.0% | 1,142,653 | $29.9M |
| Mackenzie Financial Corp. | 0.04% | Reduce -19.3% | 1,138,559 | $29.8M |
| Van Lanschot Kempen Investment Management N.V. | 0.27% | Add +261.6% | 815,678 | $29.7M |
| Clearbridge Investments, LLC | 0.02% | Reduce -38.8% | 1,130,381 | $29.6M |
| MIRAE ASSET GLOBAL ETFS HOLDINGS Ltd. | 0.05% | Reduce -0.3% | 1,109,230 | $29.0M |
| Janus Henderson Group PLC | 0.01% | Reduce -2.6% | 898,343 | $23.5M |
| Principal Financial Group Inc. | 0.01% | Add +11.6% | 874,140 | $22.9M |
| Healthcare of Ontario Pension Plan Trust Fund | 0.04% | Reduce -10.5% | 753,492 | $19.7M |
| 1832 Asset Management L.P. | 0.03% | Reduce -10.4% | 738,731 | $19.4M |
| Massachusetts Financial Services Co. | 0.00% | Reduce -9.7% | 569,674 | $14.9M |
| Goldman Sachs Group Inc. | 0.00% | Reduce -8.8% | 507,885 | $13.3M |
| Legal & General Group Plc | 0.00% | Add +12.8% | 494,609 | $13.0M |
| Agf Management Ltd. | 0.06% | No change | 489,956 | $12.8M |
| Galibier Capital Management Ltd. | 3.90% | Reduce -8.0% | 447,446 | $11.7M |
| National Bank of Canada | 0.01% | Reduce -4.3% | 420,025 | $10.8M |
| Foresight Group Ltd Liability Partnership | 1.52% | Add +1.9% | 388,892 | $10.2M |
| Cibc World Market Inc. | 0.02% | Reduce -0.1% | 369,513 | $9.7M |
| JARISLOWSKY, FRASER Ltd | 0.05% | Reduce -11.7% | 334,904 | $8.8M |
| Front Street Capital Management, Inc. | 1.17% | Reduce -1.4% | 289,772 | $7.6M |
| Montrusco Bolton Investments Inc. | 0.09% | Reduce -11.0% | 283,781 | $7.4M |
| Van Berkom & Associates Inc. | 0.20% | Add +0.3% | 269,994 | $7.1M |
| UBS Group AG | 0.00% | Reduce -10.0% | 231,595 | $6.1M |
| Charles Schwab Investment Management Inc. | 0.00% | Add +15.1% | 230,506 | $6.0M |
| Roubaix Capital, LLC | 2.73% | New | 223,532 | $5.9M |
| Dixon Mitchell Investment Counsel Inc. | 0.20% | Reduce -45.7% | 218,525 | $5.7M |
| D. E. Shaw & Co. | 0.00% | Add +272.0% | 217,900 | $5.7M |
| Louisbourg Investments Inc. | 1.23% | Add +112.1% | 215,295 | $5.6M |
| Granite Investment Partners, LLC | 0.31% | Add +34.5% | 205,847 | $5.4M |
| Scotia Capital Inc. | 0.02% | Add +2.6% | 209,018 | $5.4M |
| Federation des caisses Desjardins du Quebec | 0.02% | Reduce -26.9% | 195,234 | $5.0M |
| Focus Partners Wealth | 0.01% | New | 181,988 | $4.8M |
| Swiss National Bank | 0.00% | No change | 160,100 | $4.2M |
| First Trust Advisors LP | 0.00% | Add +23.8% | 148,712 | $3.9M |
| CIBC Asset Management Inc | 0.01% | Add +69.2% | 134,854 | $3.5M |
| Royce & Associates LP | 0.04% | Add +7.2% | 134,500 | $3.5M |
| Fiera Capital Corp | 0.01% | Reduce -29.6% | 93,159 | $2.4M |
| Zurcher Kantonalbank (Zurich Cantonalbank) | 0.01% | Add +235.8% | 91,611 | $2.4M |
| Dimensional Fund Advisors LP | 0.00% | Add +15.8% | 89,223 | $2.3M |
| Canoe Financial LP | 0.03% | Reduce -2.8% | 78,877 | $2.1M |
| Toronto Dominion Bank | 0.00% | Add +80.3% | 77,955 | $2.0M |
| Manufacturers Life Insurance Company, The | 0.00% | Add +21.1% | 76,460 | $2.0M |
| Bastion Asset Management Inc. | 1.10% | New | 72,655 | $1.9M |
| Citadel Advisors | 0.00% | Add +167.6% | 69,820 | $1.8M |
| Morgan Stanley | 0.00% | Reduce -46.8% | 69,639 | $1.8M |
| Nuveen, LLC | 0.00% | No change | 62,584 | $1.6M |
| Public Sector Pension Investment Board | 0.01% | New | 61,906 | $1.6M |
| Caldwell Investment Management Ltd. | 1.05% | No change | 60,800 | $1.6M |
| Aviso Financial Inc. | 0.06% | Add +3.1% | 52,243 | $1.4M |
| Geode Capital Management, LLC | 0.00% | Add +9.6% | 50,232 | $1.3M |
| Blackstone Inc. | 0.01% | New | 49,501 | $1.3M |
| BRITISH COLUMBIA INVESTMENT MANAGEMENT Corp | 0.01% | Reduce -5.4% | 47,806 | $1.3M |
| Millennium Management | 0.00% | New | 43,821 | $1.1M |
| Russell Investments Group, Ltd. | 0.00% | Add +10.8% | 33,085 | $866K |
| Main Management ETF Advisors, LLC | 0.03% | New | 29,450 | $772K |
| Lombard Odier Asset Management (Switzerland) SA | 0.04% | Reduce -45.6% | 21,515 | $771K |
| Rockefeller Capital Management L.P. | 0.00% | Reduce -0.5% | 28,731 | $752K |
| Amundi | 0.00% | No change | 27,180 | $727K |
| Public Employees Retirement System of Ohio | 0.00% | Add +0.2% | 27,205 | $712K |
| Bank of Nova Scotia Trust Co. | 0.06% | Add +15.0% | 25,075 | $657K |
| PenderFund Capital Management Ltd. | 0.20% | New | 20,000 | $523K |
| Aberdeen Group plc | 0.00% | Add +14.8% | 18,595 | $489K |
| Envestnet Asset Management Inc. | 0.00% | Reduce -21.9% | 17,794 | $466K |
| Citigroup Inc. | 0.00% | Add +30.4% | 16,442 | $430K |
| Franklin Resources Inc. | 0.00% | Reduce -7.5% | 15,830 | $414K |
| Pictet Asset Management Holding SA | 0.00% | Add +12.0% | 15,538 | $407K |
| XTX Topco Ltd | 0.02% | Add +24.5% | 13,621 | $357K |
| Stifel Financial Corp. | 0.00% | Add +29.4% | 12,126 | $318K |
| TRUE Private Wealth Advisors | 0.03% | No change | 12,080 | $316K |
| Deutsche Bank AG | 0.00% | Add +9.3% | 10,888 | $285K |
| Boothbay Fund Management, LLC | 0.01% | Add +52.4% | 10,170 | $266K |
| Alliancebernstein L.P. | 0.00% | Reduce -29.9% | 9,820 | $257K |
| Mariner, LLC | 0.00% | Reduce -42.3% | 9,024 | $236K |
| Northwest & Ethical Investments L.P. | 0.01% | Reduce -70.8% | 8,613 | $225K |
| Van Eck Associates Corp. | 0.00% | Add +17.2% | 6,012 | $158K |
| Quantbot Technologies LP | 0.00% | New | 4,665 | $122K |
| Barclays PLC | 0.00% | Reduce -79.2% | 4,508 | $118K |
| State of Wyoming | 0.01% | New | 4,262 | $112K |
| Shell Asset Management Co. | 0.00% | Reduce -69.9% | 1,302 | $34K |
| Quarry LP | 0.01% | New | 1,238 | $32K |
| Tower Research Capital LLC (TRC) | 0.00% | Reduce -88.7% | 1,000 | $26K |
| JPMorgan Chase & Co. | 0.00% | Add +101.7% | 714 | $19K |
"% of holder's portfolio" is ATS's weight in each manager's 13F, not the share of Ats Corp. the manager owns.