ATS US Equity

ATS Corp /ATS

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Industrials · General Industrial Machinery & Equipment, NEC · CIK 1394832 · FYE 0331

$26.97

+0.38 (+1.43%)

USD · as of 2026-07-28 · marketstack

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Institutional ownership· 13F filers holding ATS · 2026-Q1 methodology → sources →

128 holders

% of shares outstanding held

87.9%

Shares held (13F)

85,180,533

Reporting holders

128

Top holders

largest 100 of 128 · Δ vs 2025-Q4

#	Holder	Shares	Value	% of shares out	Δ QoQ
1	MASON CAPITAL MANAGEMENT LLC	16,404,17016.4M	$463M	16.93%	ADD 5%
2	ROYAL BANK OF CANADA	7,761,8387.8M	$219M	8.01%	—
3	EdgePoint Investment Group Inc.	7,168,1127.2M	$202M	7.40%	ADD 4%
4	Beutel, Goodman & Co Ltd.	5,454,7495.5M	$153M	5.63%	TRIM -7%
5	TURTLE CREEK ASSET MANAGEMENT INC.	4,896,6694.9M	$138M	5.05%	TRIM -13%
6	BANK OF MONTREAL /CAN/	3,115,3603.1M	$88M	3.22%	ADD 3%
7	FAIRFAX FINANCIAL HOLDINGS LTD/ CAN	2,486,4002.5M	$69M	2.57%	—
8	VANGUARD CAPITAL MANAGEMENT LLC	2,366,7302.4M	$67M	2.44%	NEW†
9	JANUS HENDERSON GROUP PLC	2,297,2142.3M	$65M	2.37%	ADD 167%
10	FMR LLC	2,277,4722.3M	$64M	2.35%	ADD 8%
11	Connor, Clark & Lunn Investment Management Ltd.	2,264,7572.3M	$64M	2.34%	TRIM -9%
12	ACK Asset Management LLC	1,846,1961.8M	$52M	1.91%	—
13	FIL Ltd	1,778,1811.8M	$50M	1.84%	ADD 3219%
14	TD Waterhouse Canada Inc.	1,634,4491.6M	$47M	1.69%	ADD 69%
15	Hill City Capital, LP	1,649,8571.6M	$47M	1.70%	—
16	TD Asset Management Inc	1,422,4591.4M	$40M	1.47%	ADD 19%
17	Vinva Investment Management Ltd	2,088,9472.1M	$37M	2.16%	NEW†
18	VAN LANSCHOT KEMPEN INVESTMENT MANAGEMENT N.V.	863,486863,486	$34M	0.89%	ADD 6%
19	Scheer, Rowlett & Associates Investment Management Ltd.	1,181,9371.2M	$33M	1.22%	TRIM -4%
20	Clearbridge Investments, LLC	1,091,2911.1M	$31M	1.13%	—
21	Marathon Asset Management Ltd	1,093,9111.1M	$31M	1.13%	—
22	BANK OF AMERICA CORP /DE/	945,875945,875	$27M	0.98%	TRIM -14%
23	Alberta Investment Management Corp	940,191940,191	$27M	0.97%	TRIM -30%
24	MIRAE ASSET GLOBAL ETFS HOLDINGS Ltd.	758,313758,313	$21M	0.78%	TRIM -34%
25	MASSACHUSETTS FINANCIAL SERVICES CO /MA/	533,957533,957	$21M	0.55%	TRIM -4%
26	VANGUARD FIDUCIARY TRUST CO	728,058728,058	$21M	0.75%	NEW
27	NATIONAL BANK OF CANADA /FI/	648,282648,282	$18M	0.67%	ADD 55%
28	PRINCIPAL FINANCIAL GROUP INC	620,840620,840	$17M	0.64%	TRIM -29%
29	MACKENZIE FINANCIAL CORP	616,504616,504	$17M	0.64%	TRIM -19%
30	Legal & General Group Plc	611,689611,689	$17M	0.63%	ADD 13%
31	Van Berkom & Associates Inc.	514,720514,720	$14M	0.53%	ADD 91%
32	1832 Asset Management L.P.	401,696401,696	$11M	0.41%	TRIM -51%
33	Public Sector Pension Investment Board	356,837356,837	$10M	0.37%	ADD 24%
34	CIBC WORLD MARKET INC.	346,606346,606	$10M	0.36%	TRIM -2%
35	Invesco Ltd.	343,176343,176	$10M	0.35%	TRIM -73%
36	Front Street Capital Management, Inc.	261,088261,088	$7M	0.27%	TRIM -9%
37	Vanguard Global Advisers, LLC	258,998258,998	$7M	0.27%	NEW
38	FRANKLIN RESOURCES INC	247,467247,467	$7M	0.26%	ADD 875%
39	CHARLES SCHWAB INVESTMENT MANAGEMENT INC	238,654238,654	$7M	0.25%	—
40	UBS Group AG	227,628227,628	$6M	0.23%	—
41	Waratah Capital Advisors Ltd.	223,983223,983	$6M	0.23%	NEW
42	Dixon Mitchell Investment Counsel Inc.	211,025211,025	$6M	0.22%	—
43	SCOTIA CAPITAL INC.	192,530192,530	$5M	0.20%	—
44	Focus Partners Wealth	181,975181,975	$5M	0.19%	—
45	ROYCE & ASSOCIATES LP	179,500179,500	$5M	0.19%	ADD 9%
46	ArrowMark Colorado Holdings LLC	174,000174,000	$5M	0.18%	NEW
47	Granite Investment Partners, LLC	173,031173,031	$5M	0.18%	TRIM -15%
48	MONTRUSCO BOLTON INVESTMENTS INC.	170,956170,956	$5M	0.18%	TRIM -33%
49	SEI INVESTMENTS CO	167,820167,820	$5M	0.17%	ADD 70%
50	Swiss National Bank	164,400164,400	$5M	0.17%	—
51	FIRST TRUST ADVISORS LP	154,403154,403	$4M	0.16%	TRIM -16%
52	Candelo Capital Management LP	151,688151,688	$4M	0.16%	ADD 514%
53	CIBC Asset Management Inc	134,186134,186	$4M	0.14%	ADD 2%
54	DIMENSIONAL FUND ADVISORS LP	122,456122,456	$3M	0.13%	ADD 11%
55	Federation des caisses Desjardins du Quebec	113,047113,047	$3M	0.12%	TRIM -3%
56	HARBOR CAPITAL ADVISORS, INC.	103,168103,168	$3M	0.11%	NEW
57	MORGAN STANLEY	100,390100,390	$3M	0.10%	ADD 367%
58	TORONTO DOMINION BANK	93,17593,175	$3M	0.10%	ADD 14%
59	Canoe Financial LP	87,43087,430	$2M	0.09%	ADD 8%
60	LOUISBOURG INVESTMENTS INC.	84,85584,855	$2M	0.09%	TRIM -59%
61	JANE STREET GROUP, LLC	82,64182,641	$2M	0.09%	ADD 275%
62	CITADEL ADVISORS LLC	81,23981,239	$2M	0.08%	TRIM -45%
63	MANUFACTURERS LIFE INSURANCE COMPANY, THE	74,13074,130	$2M	0.08%	TRIM -3%
64	BRITISH COLUMBIA INVESTMENT MANAGEMENT Corp	70,42270,422	$2M	0.07%	ADD 61%
65	GEODE CAPITAL MANAGEMENT, LLC	68,79868,798	$2M	0.07%	ADD 16%
66	LAZARD ASSET MANAGEMENT LLC	69,91269,912	$2M	0.07%	ADD 20%
67	VANGUARD ASSET MANAGEMENT, Ltd	66,83066,830	$2M	0.07%	NEW
68	Nuveen, LLC	62,58462,584	$2M	0.06%	—
69	Caldwell Investment Management Ltd.	60,80060,800	$2M	0.06%	—
70	INTACT INVESTMENT MANAGEMENT INC.	53,38953,389	$2M	0.06%	NEW
71	GOLDMAN SACHS GROUP INC	52,25152,251	$1M	0.05%	TRIM -82%
72	PCJ Investment Counsel Ltd.	50,00050,000	$1M	0.05%	NEW
73	GUARDIAN CAPITAL LP	46,95546,955	$1M	0.05%	—
74	Aviso Financial Inc.	45,76045,760	$1M	0.05%	TRIM -12%
75	BANK OF NOVA SCOTIA TRUST CO	34,33234,332	$968,163	0.04%	ADD 13%
76	Zurcher Kantonalbank (Zurich Cantonalbank)	31,45031,450	$883,635	0.03%	TRIM -51%
77	D. E. Shaw & Co., Inc.	30,20030,200	$850,982	0.03%	TRIM -72%
78	Purpose Unlimited Inc.	28,56728,567	$805,170	0.03%	—
79	Numerai GP LLC	27,53827,538	$776,572	0.03%	ADD 69%
80	PUBLIC EMPLOYEES RETIREMENT SYSTEM OF OHIO	27,33527,335	$767,824	0.03%	—
81	CITIGROUP INC	26,81626,816	$753,434	0.03%	ADD 7%
82	SIG North Trading, ULC	26,27526,275	$740,955	0.03%	TRIM -10%
83	Aberdeen Group plc	26,23726,237	$739,883	0.03%	ADD 31%
84	VAN ECK ASSOCIATES CORP	24,27124,271	$684,000	0.03%	ADD 79%
85	ExodusPoint Capital Management, LP	22,05022,050	$621,810	0.02%	NEW
86	PenderFund Capital Management Ltd.	20,00020,000	$563,727	0.02%	—
87	Vanguard Investments Australia, Ltd.	19,31519,315	$544,413	0.02%	NEW
88	Pictet Asset Management Holding SA	16,42316,423	$461,428	0.02%	ADD 3%
89	Mariner, LLC	16,23716,237	$457,860	0.02%	ADD 33%
90	Balyasny Asset Management L.P.	14,12414,124	$398,297	0.01%	NEW
91	Engineers Gate Manager LP	13,05213,052	$367,989	0.01%	NEW
92	Savant Capital, LLC	12,65712,657	$356,928	0.01%	ADD 11%
93	TRUE Private Wealth Advisors	12,08012,080	$340,656	0.01%	—
94	STIFEL FINANCIAL CORP	11,89111,891	$335,325	0.01%	TRIM -6%
95	Investment Management Corp of Ontario	11,71611,716	$330,391	0.01%	ADD 16%
96	Northwest & Ethical Investments L.P.	10,98310,983	$309,366	0.01%	ADD 4%
97	SkyView Investment Advisors, LLC	10,96610,966	$309,000	0.01%	—
98	DEUTSCHE BANK AG\	10,75210,752	$303,207	0.01%	ADD 5%
99	MARSHALL WACE, LLP	9,9209,920	$279,744	0.01%	NEW
100	ALLIANCEBERNSTEIN L.P.	8,9608,960	$246,758	0.01%	—

† a filer this large appearing as NEW usually reflects a renamed or succeeded filing entity (the old name stops filing the same quarter) — not a brand-new position.

Rows rank by the value each filer reported — 13F filers price their own positions, so a holder with fewer shares can rank just above one with more.

Holder trends· top 15 holders · shares held over 6 quarters

green added · red trimmed

Holder

2024-Q4

2025-Q1

2025-Q2

2025-Q3

2025-Q4

2026-Q1

Latest value

MASON CAPITAL MANAGEMENT LLC

14.9M

15.6M

16.4M

$463M

ROYAL BANK OF CANADA

5.3M

6.5M

14.1M

7.2M

7.6M

7.8M

$219M

EdgePoint Investment Group Inc.

3.5M

5.0M

6.4M

6.9M

7.2M

$202M

Beutel, Goodman & Co Ltd.

6.5M

7.1M

6.8M

6.3M

5.8M

5.5M

$153M

TURTLE CREEK ASSET MANAGEMENT INC.

8.3M

7.6M

7.0M

5.6M

4.9M

$138M

BANK OF MONTREAL /CAN/

962K

1.0M

1.1M

3.0M

3.1M

$88M

FAIRFAX FINANCIAL HOLDINGS LTD/ CAN

2.5M

$69M

VANGUARD CAPITAL MANAGEMENT LLC

—

2.4M

$67M

JANUS HENDERSON GROUP PLC

923K

922K

898K

862K

2.3M

$65M

FMR LLC

2.1M

1.5M

1.4M

2.1M

2.3M

$64M

Connor, Clark & Lunn Investment Management Ltd.

1.7M

2.0M

2.4M

2.1M

2.5M

2.3M

$64M

ACK Asset Management LLC

2.1M

2.0M

1.8M

$52M

FIL Ltd

1.9M

816K

35K

—

54K

1.8M

$50M

TD Waterhouse Canada Inc.

1.6M

1.7M

1.5M

1.4M

966K

1.6M

$47M

Hill City Capital, LP

—

1.3M

1.2M

1.6M

$47M

Shares reported each quarter by the largest current holders. Green = added vs the prior filing, red = trimmed, grey = roughly held; a dash is a quarter with no 13F on file (a gap is skipped, not read as an exit). 13F is filed up to 45 days after quarter-end. Up to 40 quarters (10 years) available — use the selector above.

Institutional footprint by quarter

Line breaks are honest gaps — quarters with no 13F record, or a suppressed % — never interpolated. % of shares outstanding uses today's share count for every quarter (the only count stored).

Quarter	Holders	Shares held	% shares out	Value held
2026-Q1	128	85,180,533	87.9%	$2.4B
2025-Q4	121	83,011,700	85.7%	$2.3B
2025-Q3	115	83,528,045	86.2%	$2.2B
2025-Q2	131	93,893,403	96.9%	$3.0B
2025-Q1	122	87,355,519	90.2%	$2.2B
2024-Q4	129	88,090,999	90.9%	$2.7B
2024-Q3	130	81,071,545	83.7%	$2.4B
2024-Q2	132	81,866,679	84.5%	$2.6B
2024-Q1	136	77,550,301	80.0%	$2.8B
2023-Q4	132	76,294,712	78.7%	$3.3B
2023-Q3	127	74,953,905	77.4%	$3.2B
2023-Q2	130	76,176,214	78.6%	$3.5B

Short interest has its own tab now — open SI →

Source: SEC Form 13F — every institution manager (≥ $100M in 13F securities) reporting a long US-listed position, across ~10,250 filers over 10 years of history. 13F is long-only, US-listed, filed up to 45 days after quarter-end.

Institutional ownership· 13F filers holding ATS · 2026-Q1 methodology → sources →

128 holders

% of shares outstanding held

87.9%

Shares held (13F)

85,180,533

Reporting holders

128

Top holders

largest 100 of 128 · Δ vs 2025-Q4

#	Holder	Shares	Value	% of shares out	Δ QoQ
1	MASON CAPITAL MANAGEMENT LLC	16,404,17016.4M	$463M	16.93%	ADD 5%
2	ROYAL BANK OF CANADA	7,761,8387.8M	$219M	8.01%	—
3	EdgePoint Investment Group Inc.	7,168,1127.2M	$202M	7.40%	ADD 4%
4	Beutel, Goodman & Co Ltd.	5,454,7495.5M	$153M	5.63%	TRIM -7%
5	TURTLE CREEK ASSET MANAGEMENT INC.	4,896,6694.9M	$138M	5.05%	TRIM -13%
6	BANK OF MONTREAL /CAN/	3,115,3603.1M	$88M	3.22%	ADD 3%
7	FAIRFAX FINANCIAL HOLDINGS LTD/ CAN	2,486,4002.5M	$69M	2.57%	—
8	VANGUARD CAPITAL MANAGEMENT LLC	2,366,7302.4M	$67M	2.44%	NEW†
9	JANUS HENDERSON GROUP PLC	2,297,2142.3M	$65M	2.37%	ADD 167%
10	FMR LLC	2,277,4722.3M	$64M	2.35%	ADD 8%
11	Connor, Clark & Lunn Investment Management Ltd.	2,264,7572.3M	$64M	2.34%	TRIM -9%
12	ACK Asset Management LLC	1,846,1961.8M	$52M	1.91%	—
13	FIL Ltd	1,778,1811.8M	$50M	1.84%	ADD 3219%
14	TD Waterhouse Canada Inc.	1,634,4491.6M	$47M	1.69%	ADD 69%
15	Hill City Capital, LP	1,649,8571.6M	$47M	1.70%	—
16	TD Asset Management Inc	1,422,4591.4M	$40M	1.47%	ADD 19%
17	Vinva Investment Management Ltd	2,088,9472.1M	$37M	2.16%	NEW†
18	VAN LANSCHOT KEMPEN INVESTMENT MANAGEMENT N.V.	863,486863,486	$34M	0.89%	ADD 6%
19	Scheer, Rowlett & Associates Investment Management Ltd.	1,181,9371.2M	$33M	1.22%	TRIM -4%
20	Clearbridge Investments, LLC	1,091,2911.1M	$31M	1.13%	—
21	Marathon Asset Management Ltd	1,093,9111.1M	$31M	1.13%	—
22	BANK OF AMERICA CORP /DE/	945,875945,875	$27M	0.98%	TRIM -14%
23	Alberta Investment Management Corp	940,191940,191	$27M	0.97%	TRIM -30%
24	MIRAE ASSET GLOBAL ETFS HOLDINGS Ltd.	758,313758,313	$21M	0.78%	TRIM -34%
25	MASSACHUSETTS FINANCIAL SERVICES CO /MA/	533,957533,957	$21M	0.55%	TRIM -4%
26	VANGUARD FIDUCIARY TRUST CO	728,058728,058	$21M	0.75%	NEW
27	NATIONAL BANK OF CANADA /FI/	648,282648,282	$18M	0.67%	ADD 55%
28	PRINCIPAL FINANCIAL GROUP INC	620,840620,840	$17M	0.64%	TRIM -29%
29	MACKENZIE FINANCIAL CORP	616,504616,504	$17M	0.64%	TRIM -19%
30	Legal & General Group Plc	611,689611,689	$17M	0.63%	ADD 13%
31	Van Berkom & Associates Inc.	514,720514,720	$14M	0.53%	ADD 91%
32	1832 Asset Management L.P.	401,696401,696	$11M	0.41%	TRIM -51%
33	Public Sector Pension Investment Board	356,837356,837	$10M	0.37%	ADD 24%
34	CIBC WORLD MARKET INC.	346,606346,606	$10M	0.36%	TRIM -2%
35	Invesco Ltd.	343,176343,176	$10M	0.35%	TRIM -73%
36	Front Street Capital Management, Inc.	261,088261,088	$7M	0.27%	TRIM -9%
37	Vanguard Global Advisers, LLC	258,998258,998	$7M	0.27%	NEW
38	FRANKLIN RESOURCES INC	247,467247,467	$7M	0.26%	ADD 875%
39	CHARLES SCHWAB INVESTMENT MANAGEMENT INC	238,654238,654	$7M	0.25%	—
40	UBS Group AG	227,628227,628	$6M	0.23%	—
41	Waratah Capital Advisors Ltd.	223,983223,983	$6M	0.23%	NEW
42	Dixon Mitchell Investment Counsel Inc.	211,025211,025	$6M	0.22%	—
43	SCOTIA CAPITAL INC.	192,530192,530	$5M	0.20%	—
44	Focus Partners Wealth	181,975181,975	$5M	0.19%	—
45	ROYCE & ASSOCIATES LP	179,500179,500	$5M	0.19%	ADD 9%
46	ArrowMark Colorado Holdings LLC	174,000174,000	$5M	0.18%	NEW
47	Granite Investment Partners, LLC	173,031173,031	$5M	0.18%	TRIM -15%
48	MONTRUSCO BOLTON INVESTMENTS INC.	170,956170,956	$5M	0.18%	TRIM -33%
49	SEI INVESTMENTS CO	167,820167,820	$5M	0.17%	ADD 70%
50	Swiss National Bank	164,400164,400	$5M	0.17%	—
51	FIRST TRUST ADVISORS LP	154,403154,403	$4M	0.16%	TRIM -16%
52	Candelo Capital Management LP	151,688151,688	$4M	0.16%	ADD 514%
53	CIBC Asset Management Inc	134,186134,186	$4M	0.14%	ADD 2%
54	DIMENSIONAL FUND ADVISORS LP	122,456122,456	$3M	0.13%	ADD 11%
55	Federation des caisses Desjardins du Quebec	113,047113,047	$3M	0.12%	TRIM -3%
56	HARBOR CAPITAL ADVISORS, INC.	103,168103,168	$3M	0.11%	NEW
57	MORGAN STANLEY	100,390100,390	$3M	0.10%	ADD 367%
58	TORONTO DOMINION BANK	93,17593,175	$3M	0.10%	ADD 14%
59	Canoe Financial LP	87,43087,430	$2M	0.09%	ADD 8%
60	LOUISBOURG INVESTMENTS INC.	84,85584,855	$2M	0.09%	TRIM -59%
61	JANE STREET GROUP, LLC	82,64182,641	$2M	0.09%	ADD 275%
62	CITADEL ADVISORS LLC	81,23981,239	$2M	0.08%	TRIM -45%
63	MANUFACTURERS LIFE INSURANCE COMPANY, THE	74,13074,130	$2M	0.08%	TRIM -3%
64	BRITISH COLUMBIA INVESTMENT MANAGEMENT Corp	70,42270,422	$2M	0.07%	ADD 61%
65	GEODE CAPITAL MANAGEMENT, LLC	68,79868,798	$2M	0.07%	ADD 16%
66	LAZARD ASSET MANAGEMENT LLC	69,91269,912	$2M	0.07%	ADD 20%
67	VANGUARD ASSET MANAGEMENT, Ltd	66,83066,830	$2M	0.07%	NEW
68	Nuveen, LLC	62,58462,584	$2M	0.06%	—
69	Caldwell Investment Management Ltd.	60,80060,800	$2M	0.06%	—
70	INTACT INVESTMENT MANAGEMENT INC.	53,38953,389	$2M	0.06%	NEW
71	GOLDMAN SACHS GROUP INC	52,25152,251	$1M	0.05%	TRIM -82%
72	PCJ Investment Counsel Ltd.	50,00050,000	$1M	0.05%	NEW
73	GUARDIAN CAPITAL LP	46,95546,955	$1M	0.05%	—
74	Aviso Financial Inc.	45,76045,760	$1M	0.05%	TRIM -12%
75	BANK OF NOVA SCOTIA TRUST CO	34,33234,332	$968,163	0.04%	ADD 13%
76	Zurcher Kantonalbank (Zurich Cantonalbank)	31,45031,450	$883,635	0.03%	TRIM -51%
77	D. E. Shaw & Co., Inc.	30,20030,200	$850,982	0.03%	TRIM -72%
78	Purpose Unlimited Inc.	28,56728,567	$805,170	0.03%	—
79	Numerai GP LLC	27,53827,538	$776,572	0.03%	ADD 69%
80	PUBLIC EMPLOYEES RETIREMENT SYSTEM OF OHIO	27,33527,335	$767,824	0.03%	—
81	CITIGROUP INC	26,81626,816	$753,434	0.03%	ADD 7%
82	SIG North Trading, ULC	26,27526,275	$740,955	0.03%	TRIM -10%
83	Aberdeen Group plc	26,23726,237	$739,883	0.03%	ADD 31%
84	VAN ECK ASSOCIATES CORP	24,27124,271	$684,000	0.03%	ADD 79%
85	ExodusPoint Capital Management, LP	22,05022,050	$621,810	0.02%	NEW
86	PenderFund Capital Management Ltd.	20,00020,000	$563,727	0.02%	—
87	Vanguard Investments Australia, Ltd.	19,31519,315	$544,413	0.02%	NEW
88	Pictet Asset Management Holding SA	16,42316,423	$461,428	0.02%	ADD 3%
89	Mariner, LLC	16,23716,237	$457,860	0.02%	ADD 33%
90	Balyasny Asset Management L.P.	14,12414,124	$398,297	0.01%	NEW
91	Engineers Gate Manager LP	13,05213,052	$367,989	0.01%	NEW
92	Savant Capital, LLC	12,65712,657	$356,928	0.01%	ADD 11%
93	TRUE Private Wealth Advisors	12,08012,080	$340,656	0.01%	—
94	STIFEL FINANCIAL CORP	11,89111,891	$335,325	0.01%	TRIM -6%
95	Investment Management Corp of Ontario	11,71611,716	$330,391	0.01%	ADD 16%
96	Northwest & Ethical Investments L.P.	10,98310,983	$309,366	0.01%	ADD 4%
97	SkyView Investment Advisors, LLC	10,96610,966	$309,000	0.01%	—
98	DEUTSCHE BANK AG\	10,75210,752	$303,207	0.01%	ADD 5%
99	MARSHALL WACE, LLP	9,9209,920	$279,744	0.01%	NEW
100	ALLIANCEBERNSTEIN L.P.	8,9608,960	$246,758	0.01%	—

† a filer this large appearing as NEW usually reflects a renamed or succeeded filing entity (the old name stops filing the same quarter) — not a brand-new position.

Rows rank by the value each filer reported — 13F filers price their own positions, so a holder with fewer shares can rank just above one with more.

Holder trends· top 15 holders · shares held over 6 quarters

green added · red trimmed

Holder

2024-Q4

2025-Q1

2025-Q2

2025-Q3

2025-Q4

2026-Q1

Latest value

MASON CAPITAL MANAGEMENT LLC

14.9M

15.6M

16.4M

$463M

ROYAL BANK OF CANADA

5.3M

6.5M

14.1M

7.2M

7.6M

7.8M

$219M

EdgePoint Investment Group Inc.

3.5M

5.0M

6.4M

6.9M

7.2M

$202M

Beutel, Goodman & Co Ltd.

6.5M

7.1M

6.8M

6.3M

5.8M

5.5M

$153M

TURTLE CREEK ASSET MANAGEMENT INC.

8.3M

7.6M

7.0M

5.6M

4.9M

$138M

BANK OF MONTREAL /CAN/

962K

1.0M

1.1M

3.0M

3.1M

$88M

FAIRFAX FINANCIAL HOLDINGS LTD/ CAN

2.5M

$69M

VANGUARD CAPITAL MANAGEMENT LLC

—

2.4M

$67M

JANUS HENDERSON GROUP PLC

923K

922K

898K

862K

2.3M

$65M

FMR LLC

2.1M

1.5M

1.4M

2.1M

2.3M

$64M

Connor, Clark & Lunn Investment Management Ltd.

1.7M

2.0M

2.4M

2.1M

2.5M

2.3M

$64M

ACK Asset Management LLC

2.1M

2.0M

1.8M

$52M

FIL Ltd

1.9M

816K

35K

—

54K

1.8M

$50M

TD Waterhouse Canada Inc.

1.6M

1.7M

1.5M

1.4M

966K

1.6M

$47M

Hill City Capital, LP

—

1.3M

1.2M

1.6M

$47M

Institutional footprint by quarter

Line breaks are honest gaps — quarters with no 13F record, or a suppressed % — never interpolated. % of shares outstanding uses today's share count for every quarter (the only count stored).

Quarter	Holders	Shares held	% shares out	Value held
2026-Q1	128	85,180,533	87.9%	$2.4B
2025-Q4	121	83,011,700	85.7%	$2.3B
2025-Q3	115	83,528,045	86.2%	$2.2B
2025-Q2	131	93,893,403	96.9%	$3.0B
2025-Q1	122	87,355,519	90.2%	$2.2B
2024-Q4	129	88,090,999	90.9%	$2.7B
2024-Q3	130	81,071,545	83.7%	$2.4B
2024-Q2	132	81,866,679	84.5%	$2.6B
2024-Q1	136	77,550,301	80.0%	$2.8B
2023-Q4	132	76,294,712	78.7%	$3.3B
2023-Q3	127	74,953,905	77.4%	$3.2B
2023-Q2	130	76,176,214	78.6%	$3.5B

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Institutional ownership· 13F filers holding ATS · 2026-Q1 methodology → sources →

Top holders

Holder trends· top 15 holders · shares held over 6 quarters

Institutional footprint by quarter

Institutional ownership· 13F filers holding ATS · 2026-Q1 methodology → sources →

Top holders

Holder trends· top 15 holders · shares held over 6 quarters

Institutional footprint by quarter

ATS US Equity