Arkolith/Funds/Mackay Shields LLC

Mackay Shields LLC

CIK 61227
Holdings as of Jun 30, 2026·disclosed Jul 28, 2026·~28-day 13F lag·13F-HR
Active Filer

Mackay Shields LLC holds a diversified book of 108 stocks worth $3.0B as of Q2 2026 (disclosed Jul 28, 2026, a ~28-day 13F lag). This quarter they opened Alphabet Inc and trimmed Western Digital Corp. Their largest long position is Western Digital Corp at 5% of the equity book.

Opened
40
bought for the first time
  • Alphabet Inc
  • Merit Med Sys Inc
  • Revolution Medicines Inc
  • +37 more · largest first
Added to
16
already held, bought more
Trimmed
59
sold some, still holds it
Sold out
16
exited the position entirely

Concentration

Top-heavy: diversified book

Top 5 holdings
18%
Top 10 holdings
28%
Top 20 holdings
44%

Share of the disclosed book in its largest positions. A higher top-5 share means a more concentrated, higher-conviction portfolio.

Direct sector allocation

4% mapped to company sectors

ETF / fund or unclassified
96%
Energy
2%
Financials
1%
Communication Services
0%
Consumer Discretionary
0%
Consumer Staples
0%

Direct operating-company sectors from our SIC-based security master. ETF/fund and unclassified holdings stay visible separately; this is not ETF look-through exposure.

Biggest moves: latest quarter

Estimated $ traded · quarter-end prices, no cost basis

Bought
  • ALPHABET INC
    ▲New$122.6M
  • MERIT MED SYS INC
    ▲New$41.1M
  • REVOLUTION MEDICINES INC
    ▲New$38.1M
  • JAZZ INVESTMENTS I LTDJAZZ 3.125 09/15/30
    ▲New$34.7M
  • CYBERARK SOFTWARE LTD
    ▲New$31.6M
  • CLOUDFLARE INC
    ▲New$31.5M
Trimmed / exited
  • WESTERN DIGITAL CORPWDC 3 11/15/28
    ▼−42%$109.9M
  • ADVANCED ENERGY INDAEIS 2.5 09/15/28
    ▼−88%$95.0M
  • LUMENTUM HOLDINGS INCLITE 0.5 06/15/28
    ▼−52%$90.8M
  • MIRUM PHARMACEUTICALSMIRM 4 05/01/29
    ▼−92%$78.0M
  • ON SEMICONDUCTOR CORPON 0 05/01/27
    ▼−44%$31.4M
  • NUTANIX INCNTNX 0.5 12/15/29
    ▼−44%$12.9M

Funds with the most overlap

Other tracked managers holding the same core names as Mackay Shields LLC

Manager / fundShared namesTheir $ in those
BlackRock, Inc.65 / 80$10.3B
WELLS FARGO & COMPANY/MN65 / 80$1.6B
JPMORGAN CHASE & CO63 / 80$2.1B
SEI INVESTMENTS CO63 / 80$69.2M
MORGAN STANLEY61 / 80$3.7B
FMR LLC60 / 80$4.2B
Calamos Advisors LLC59 / 80$4.0B
SSI INVESTMENT MANAGEMENT LLC58 / 80$665.6M

Ranked by the share of each fund's own book sitting in the names it shares with Mackay Shields LLC: only funds sharing at least a tenth of the book qualify. Index giants, bank custody books and market makers are excluded. They hold everything, so their overlap says nothing.

Holdings: largest first

Bars show each stock's share of the portfolio. Click a row for its position history.

108 positions
#SecurityValueShares% PortLast moveHistory
1Western Digital Corp
NOTE 3.000%11/1
$150.8M8.95M
5.1%
▼−42%
Reduced · −6.5M sh
2Alphabet Inc
DEP SHS RP1/20 A
$122.6M2.43M
4.1%
▲New
New position
3MKS Inc.
NOTE 1.250% 6/0
$107.5M36.47M
3.6%
▼−0.1%
Reduced · −40K sh
4Lumentum Hldgs Inc
NOTE 0.500% 6/1
$84.1M12.88M
2.8%
▼−52%
Reduced · −13.9M sh
5Lantheus Hldgs Inc
NOTE 2.625%12/1
$74.0M50.86M
2.5%
▼−0.1%
Reduced · −35K sh
6Hewlett Packard Enterprise C
7.625 MAND CONV
$70.2M601.3K
2.4%
▼−0.1%
Reduced · −593 sh
7Cable One Inc
NOTE 1.125% 3/1
$58.8M89.89M
2.0%
▲+16%
Added · +12.5M sh
8Qxo Inc
5.50 DEP PFD
$57.4M1.17M
1.9%
▼−0.1%
Reduced · −873 sh
9Boeing Co
DEP CONV PFD A
$56.2M828.7K
1.9%
▼−0.1%
Reduced · −740 sh
10Tetra Tech Inc New
DBCV 2.250% 8/1
$55.3M52.45M
1.9%
▼−3.8%
Reduced · −2.1M sh
11Uber Technologies Inc
NOTE 0.875%12/0
$54.3M45.36M
1.8%
▲~0%
Added · +12K sh
12Snowflake Inc
NOTE 10/0
$54.2M32.54M
1.8%
▼−0.1%
Reduced · −29K sh
13Chefs Whse Inc
NOTE 2.375%12/1
$53.0M23.71M
1.8%
▼−0.2%
Reduced · −39K sh
14Etsy Inc
NOTE 0.125%10/0
$50.9M49.89M
1.7%
▲+52%
Added · +17.1M sh
15NextEra Energy Inc
UNIT 06/01/2027
$50.5M941.0K
1.7%
▲+99%
Added · +468K sh
16PG&E Corp
NOTE 4.250%12/0
$47.5M46.45M
1.6%
▲+0.1%
Added · +69K sh
17Microchip Technology Inc.
DEP SHS REPSTG
$46.5M603.5K
1.6%
▲+0.4%
Added · +2K sh
18BlackRock Mun Target Term TR
COM SHS BEN IN
$44.8M1.97M
1.5%
▲+26%
Added · +402K sh
19Integer Hldgs Corp
DBCV 1.875% 3/1
$43.9M45.24M
1.5%
▲+0.2%
Added · +84K sh
20Apollo Global Mgmt Inc
SER A MAND CNV
$43.5M713.2K
1.5%
▼−0.1%
Reduced · −656 sh
21Liberty Media Corp Del
NOTE 2.250% 8/1
$42.1M33.89M
1.4%
▼−0.2%
Reduced · −78K sh
22Post Hldgs Inc
NOTE 2.500% 8/1
$41.7M40.16M
1.4%
▼−0.2%
Reduced · −67K sh
23Merit Med Sys Inc
NOTE 3.000% 2/0
$41.1M38.07M
1.4%
▲New
New position
24Akamai Technologies Inc
NOTE 0.375% 9/0
$40.8M34.02M
1.4%
▲+0.6%
Added · +205K sh
25On Semiconductor Corp
NOTE 5/0
$40.0M21.95M
1.3%
▼−44%
Reduced · −17.2M sh
26Nine Energy Service Inc
COMMON STOCK
$39.2M3.01M
1.3%
▼−1.8%
Reduced · −55K sh
27Datadog Inc
NOTE 12/0
$39.1M27.44M
1.3%
▼−19%
Reduced · −6.4M sh
28Revolution Medicines Inc
NOTE 0.500% 5/0
$38.1M30.34M
1.3%
▲New
New position
29Freshpet Inc
NOTE 3.000% 4/0
$37.0M31.80M
1.2%
▲~0%
Added · +9K sh
30Bridgebio Pharma Inc
NOTE 2.250% 2/0
$36.9M33.26M
1.2%
▼−0.2%
Reduced · −56K sh
31Irhythm Holdings Inc
NOTE 1.500% 9/0
$35.9M32.60M
1.2%
▼−0.1%
Reduced · −33K sh
32Live Nation Entertainment In
NOTE 2.875% 1/1
$35.6M29.74M
1.2%
—Held
33Peloton Interactive Inc
NOTE 5.500%12/0
$34.9M21.50M
1.2%
▲+11%
Added · +2.1M sh
34Fluor Corp
NOTE 1.125% 8/1
$34.7M26.17M
1.2%
▼−0.6%
Reduced · −145K sh
35Jazz Investments I Ltd
NOTE 3.125% 9/1
$34.7M20.32M
1.2%
▲New
New position
36Northern Oil & Gas Inc
NOTE 3.625% 4/1
$31.9M33.24M
1.1%
▼−0.2%
Reduced · −55K sh
37Affirm Hldgs Inc
NOTE 0.750%12/1
$31.7M27.11M
1.1%
▼−0.1%
Reduced · −37K sh
38Cyberark Software Ltd
NOTE 6/1
$31.6M19.00M
1.1%
▲New
New position
39Cloudflare Inc
NOTE 6/1
$31.5M24.87M
1.1%
▲New
New position
40Unity Software Inc
NOTE 3/1
$30.5M26.90M
1.0%
▲~0%
Added · +2K sh
41Oracle Corp
6.5 DEP CUM SR D
$29.1M645.8K
1.0%
▼−0.2%
Reduced · −1K sh
42Meritage Homes Corp
NOTE 1.750% 5/1
$29.0M28.03M
1.0%
▼−0.3%
Reduced · −94K sh
43Patrick Inds Inc
NOTE 1.750%12/0
$28.3M19.12M
0.9%
▼−0.1%
Reduced · −18K sh
44Liberty Media Corp Del
NOTE 3.750% 3/1
$28.1M24.46M
0.9%
—Held
45Burlington Stores Inc
NOTE 1.250%12/1
$28.0M17.53M
0.9%
▼−14%
Reduced · −2.9M sh
46Progress Software Corp
NOTE 3.500% 3/0
$27.5M28.59M
0.9%
▼−0.3%
Reduced · −103K sh
47Bank Of Amer Corp
7.25%CNV PFD L
$26.1M20.8K
0.9%
▼−0.3%
Reduced · −61 sh
48Parsons Corp Del
NOTE 2.625% 3/0
$25.8M26.17M
0.9%
▲+0.1%
Added · +34K sh
49Biomarin Pharmaceutical Inc
NOTE 1.250% 5/1
$25.7M26.43M
0.9%
▼−0.3%
Reduced · −68K sh
50Ishares Gold TR
ISHARES NEW
$24.8M328.0K
0.8%
▼−16%
Reduced · −62K sh
Showing 50 of 108 positions
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Filing history

As-of date vs the date the SEC received each filing

QuarterAs ofFiledPositionsValueForm
Q2 2026Jun 30, 2026Jul 28, 2026306$3.0B13F-HR
Q1 2026Mar 31, 2026Apr 27, 2026307$2.7B13F-HR
Q4 2025Dec 31, 2025Jan 29, 2026340$2.9B13F-HR
Q3 2025Sep 30, 2025Oct 27, 2025354$2.9B13F-HR
Q2 2025Jun 30, 2025Jul 24, 2025364$3.1B13F-HR
Q1 2025Mar 31, 2025Apr 29, 2025361$3.1B13F-HR
Q4 2024Dec 31, 2024Feb 4, 2025367$3.4B13F-HR
Q3 2024Sep 30, 2024Oct 31, 2024368$3.6B13F-HR
Q2 2024Jun 30, 2024Aug 8, 2024345$3.3B13F-HR
Q1 2024Mar 31, 2024May 3, 2024361$3.6B13F-HR
Q4 2023Dec 31, 2023Feb 2, 2024360$3.4B13F-HR
Q3 2023Sep 30, 2023Oct 25, 2023333$3.6B13F-HR
Q2 2023Jun 30, 2023Jul 27, 2023374$3.6B13F-HR
Q1 2023Mar 31, 2023Apr 27, 2023386$3.6B13F-HR
Q4 2022Dec 31, 2022Jan 31, 2023462$3.9B13F-HR
Q3 2022Sep 30, 2022Nov 2, 2022466$4.0B13F-HR
Q2 2022Jun 30, 2022Aug 3, 2022498$4.1B13F-HR
Q1 2022Mar 31, 2022May 13, 20221,438$11.4B13F-HR
Q4 2021Dec 31, 2021Feb 4, 20221,442$12.0B13F-HR
Q3 2021Sep 30, 2021Jan 18, 20221,395$10.6B13F-HR/A
Q2 2021Jun 30, 2021Aug 13, 20211,378$10.6B13F-HR
Q1 2021Mar 31, 2021May 14, 20212,988$13.7B13F-HR
Q4 2020Dec 31, 2020Feb 16, 20213,172$14.5B13F-HR
Amended / restated
  • Q3 2021 · filed Nov 12, 202113F-HR · superseded

Data source

Holdings from SEC EDGAR 13F-HR filings, updated quarterly, filed up to 45 days after quarter-end. Public domain. The book and weighting are long equity only; disclosed put/call options are listed separately and excluded from those totals. Price-derived performance is withheld until the price-source policy and freshness gate are green.