MACKAY SHIELDS LLC

Filed: 10/27/2025ACC: 0000061227-25-000004

📋 What this filing means

MACKAY SHIELDS LLC filed this quarterly 13F‑HR report disclosing 136 equity positions with a total reported market value of $2.94B. This filing provides a transparent view of the manager's long equity holdings as of the quarter end.

136

Positions

$2.94B

Total AUM (reported)

1.87B

Total Shares

Allocation by class

COM$249.60M8.5%

NOTE 3.500% 6/0$73.68M2.5%

5.50 DEP PFD$65.49M2.2%

DBCV 2.250% 8/1$63.49M2.2%

NOTE 0.875%12/0$63.29M2.2%

NOTE 4.000% 5/0$63.09M2.1%

NOTE 2.500% 9/1$62.74M2.1%

Portfolio Concentration

Top 3$202.66M6.9%

4–10$429.32M14.6%

11–25$706.76M24.0%

Rest$1.60B54.5%

Top 3 weight

6.9%

Top 10 weight

21.5%

Voting Authority Distribution

Total shares with voting rights: 1.87B

Sole

Full voting authority

339.09M

% of voting shares18.1%

Shared

Joint voting authority

1.53B

% of voting shares81.9%

None

No voting authority

0.00

% of voting shares0.0%

Investment Discretion (by position count)

Sole54

Shared0

Other82

Dominant voting typeShared · 81.9% of voting shares

Institutional Holdings136

Rows:

SEAGATE HDD CAYMAN

OTR

NOTE 3.500% 6/0

Shares25.57M

TypePRN

Market value$73.68M

2.51%

Sole

1.39M

Shared

24.18M

None

0.00

QXO INC

DFND

5.50 DEP PFD

Shares1.19M

TypeSH

Market value$65.49M

2.23%

Sole

168.66K

Shared

1.02M

None

0.00

TETRA TECH INC NEW

OTR

DBCV 2.250% 8/1

Shares58.60M

TypePRN

Market value$63.49M

2.16%

Sole

7.06M

Shared

51.54M

None

0.00

UBER TECHNOLOGIES INC

OTR

NOTE 0.875%12/0

Shares42.99M

TypePRN

Market value$63.29M

2.15%

Sole

6.72M

Shared

36.27M

None

0.00

MIRUM PHARMACEUTICALS INC

OTR

NOTE 4.000% 5/0

Shares26.22M

TypePRN

Market value$63.09M

2.15%

Sole

2.96M

Shared

23.26M

None

0.00

ADVANCED ENERGY INDS

OTR

NOTE 2.500% 9/1

Shares45.17M

TypePRN

Market value$62.74M

2.13%

Sole

6.82M

Shared

38.35M

None

0.00

WESTERN DIGITAL CORP

OTR

NOTE 3.000%11/1

Shares19.23M

TypePRN

Market value$61.71M

2.10%

Sole

4.84M

Shared

14.38M

None

0.00

PG&E CORP

SOLE

NOTE 4.250%12/0

Shares60.44M

TypePRN

Market value$61.26M

2.08%

Sole

7.51M

Shared

52.93M

None

0.00

LANTHEUS HLDGS INC

OTR

NOTE 2.625%12/1

Shares55.67M

TypePRN

Market value$58.68M

2.00%

Sole

6.43M

Shared

49.25M

None

0.00

BOEING CO

OTR

DEP CONV PFD A

Shares841.98K

TypeSH

Market value$58.55M

1.99%

Sole

152.86K

Shared

689.12K

None

0.00

HALOZYME THERAPEUTICS INC

DFND

NOTE 0.250% 3/0

Shares50.50M

TypePRN

Market value$57.99M

1.97%

Sole

7.70M

Shared

42.80M

None

0.00

CABLE ONE INC

OTR

NOTE 1.125% 3/1

Shares67.42M

TypePRN

Market value$57.71M

1.96%

Sole

24.99M

Shared

42.43M

None

0.00

POST HLDGS INC

OTR

NOTE 2.500% 8/1

Shares50.12M

TypePRN

Market value$56.35M

1.92%

Sole

6.78M

Shared

43.34M

None

0.00

NUTANIX INC

DFND

NOTE 0.250%10/0

Shares40.67M

TypePRN

Market value$56.05M

1.91%

Sole

6.31M

Shared

34.36M

None

0.00

APOLLO GLOBAL MGMT INC

DFND

SER A MAND CNV

Shares721.85K

TypeSH

Market value$50.99M

1.73%

Sole

121.49K

Shared

600.36K

None

0.00

OSI SYSTEMS INC

OTR

NOTE 2.250% 8/0

Shares32.54M

TypePRN

Market value$47.27M

1.61%

Sole

5.96M

Shared

26.57M

None

0.00

LIBERTY MEDIA CORP DEL

OTR

NOTE 2.250% 8/1

Shares34.43M

TypePRN

Market value$45.73M

1.56%

Sole

6.25M

Shared

28.18M

None

0.00

ON SEMICONDUCTOR CORP

DFND

NOTE 5/0

Shares39.98M

TypePRN

Market value$45.58M

1.55%

Sole

7.09M

Shared

32.89M

None

0.00

IRHYTHM TECHNOLOGIES INC

SOLE

NOTE 1.500% 9/0

Shares30.86M

TypePRN

Market value$42.49M

1.45%

Sole

1.34M

Shared

29.52M

None

0.00

LUMENTUM HLDGS INC

SOLE

NOTE 0.500% 6/1

Shares30.45M

TypePRN

Market value$42.47M

1.44%

Sole

1.96M

Shared

28.48M

None

0.00

AKAMAI TECHNOLOGIES INC

OTR

NOTE 0.375% 9/0

Shares43.44M

TypePRN

Market value$41.65M

1.42%

Sole

7.16M

Shared

36.28M

None

0.00

HEWLETT PACKARD ENTERPRISE C

OTR

7.625 MAND CONV

Shares605.18K

TypeSH

Market value$41.25M

1.40%

Sole

109.72K

Shared

495.46K

None

0.00

MKS INC.

SOLE

NOTE 1.250% 6/0

Shares37.19M

TypePRN

Market value$40.80M

1.39%

Sole

4.92M

Shared

32.27M

None

0.00

NCL CORP LTD

OTR

NOTE 1.125% 2/1

Shares39.31M

TypePRN

Market value$40.33M

1.37%

Sole

1.71M

Shared

37.60M

None

0.00

SNOWFLAKE INC

OTR

NOTE 10/0

Shares26.38M

TypePRN

Market value$40.09M

1.36%

Sole

1.38M

Shared

25.01M

None

0.00

Issuer	Class	Shares	Type	Value / Portfolio %	Voting — Sole	Shared
SEAGATE HDD CAYMANOTR	NOTE 3.500% 6/0	25.57M	PRN	$73.68M 2.51%	1.39M	24.18M
QXO INCDFND	5.50 DEP PFD	1.19M	SH	$65.49M 2.23%	168.66K	1.02M
TETRA TECH INC NEWOTR	DBCV 2.250% 8/1	58.60M	PRN	$63.49M 2.16%	7.06M	51.54M
UBER TECHNOLOGIES INCOTR	NOTE 0.875%12/0	42.99M	PRN	$63.29M 2.15%	6.72M	36.27M
MIRUM PHARMACEUTICALS INCOTR	NOTE 4.000% 5/0	26.22M	PRN	$63.09M 2.15%	2.96M	23.26M
ADVANCED ENERGY INDSOTR	NOTE 2.500% 9/1	45.17M	PRN	$62.74M 2.13%	6.82M	38.35M
WESTERN DIGITAL CORPOTR	NOTE 3.000%11/1	19.23M	PRN	$61.71M 2.10%	4.84M	14.38M
PG&E CORPSOLE	NOTE 4.250%12/0	60.44M	PRN	$61.26M 2.08%	7.51M	52.93M
LANTHEUS HLDGS INCOTR	NOTE 2.625%12/1	55.67M	PRN	$58.68M 2.00%	6.43M	49.25M
BOEING COOTR	DEP CONV PFD A	841.98K	SH	$58.55M 1.99%	152.86K	689.12K
HALOZYME THERAPEUTICS INCDFND	NOTE 0.250% 3/0	50.50M	PRN	$57.99M 1.97%	7.70M	42.80M
CABLE ONE INCOTR	NOTE 1.125% 3/1	67.42M	PRN	$57.71M 1.96%	24.99M	42.43M
POST HLDGS INCOTR	NOTE 2.500% 8/1	50.12M	PRN	$56.35M 1.92%	6.78M	43.34M
NUTANIX INCDFND	NOTE 0.250%10/0	40.67M	PRN	$56.05M 1.91%	6.31M	34.36M
APOLLO GLOBAL MGMT INCDFND	SER A MAND CNV	721.85K	SH	$50.99M 1.73%	121.49K	600.36K
OSI SYSTEMS INCOTR	NOTE 2.250% 8/0	32.54M	PRN	$47.27M 1.61%	5.96M	26.57M
LIBERTY MEDIA CORP DELOTR	NOTE 2.250% 8/1	34.43M	PRN	$45.73M 1.56%	6.25M	28.18M
ON SEMICONDUCTOR CORPDFND	NOTE 5/0	39.98M	PRN	$45.58M 1.55%	7.09M	32.89M
IRHYTHM TECHNOLOGIES INCSOLE	NOTE 1.500% 9/0	30.86M	PRN	$42.49M 1.45%	1.34M	29.52M
LUMENTUM HLDGS INCSOLE	NOTE 0.500% 6/1	30.45M	PRN	$42.47M 1.44%	1.96M	28.48M
AKAMAI TECHNOLOGIES INCOTR	NOTE 0.375% 9/0	43.44M	PRN	$41.65M 1.42%	7.16M	36.28M
HEWLETT PACKARD ENTERPRISE COTR	7.625 MAND CONV	605.18K	SH	$41.25M 1.40%	109.72K	495.46K
MKS INC.SOLE	NOTE 1.250% 6/0	37.19M	PRN	$40.80M 1.39%	4.92M	32.27M
NCL CORP LTDOTR	NOTE 1.125% 2/1	39.31M	PRN	$40.33M 1.37%	1.71M	37.60M
SNOWFLAKE INCOTR	NOTE 10/0	26.38M	PRN	$40.09M 1.36%	1.38M	25.01M

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