Institutional filer · SEC 13F · Q4 2025

MARINER INVESTMENT GROUP LLC

The reported 13F portfolio of MARINER INVESTMENT GROUP LLC (CIK 1096978) - top holdings, how concentrated the book is, and what changed last quarter.

$1.7B
Reported book
101
Positions
#44
of 360 filers
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The verdict

According to SEC Form 13F-HR filings in this corpus, MARINER INVESTMENT GROUP LLC ranks #44 of 360 institutional filers by reported book value (largest first), matching the /funds listing. As of Q4 2025 the reported book is $1.7B across 101 positions, a moderately concentrated portfolio.

$1.7B
reported 13F value
101
disclosed positions
9.7%
in MICROSOFT CORP
#44
of 360 filers

Top-5 share 36.0% → MID-PACK book (largest five positions vs the rest of the reported 13F book).

According to SEC Form 13F-HR filings in this corpus, MARINER INVESTMENT GROUP LLC ranks #44 of 360 institutional filers by reported book value (largest first), matching the /funds listing.

Where MARINER INVESTMENT GROUP LLC sits by disclosed position count

MARINER INVESTMENT GROUP LLC reports 101 13F positions among 360 filers with holdings (inventory signal, not a quality ranking). Orthogonal to book-value rank.

MARINER INVESTMENT GROUP LLC vs all filers by holding count

Where this filer's disclosed position inventory sits among every tracked 13F manager

101 188th of 360 higher than 172 of 360 filers

Filers, banded by disclosed position count

Each bar is a band; taller bars hold more filers. The dashed line + filled bar mark this entry. Hover or tap any bar for its full count and share, and where it sits relative to this entry.

Source SEC Form 13F-HR filings · 2026-05-16

Concentration vs. book size among peer filers

MARINER INVESTMENT GROUP LLC reports a book ($1.71B) concentrated across only 101 disclosed positions -- fewer than the 274-position median among similarly sized filers.

Reported book value vs. disclosed position count

16 tracked 13F filers plotted by reported book value and disclosed position count; MARINER INVESTMENT GROUP LLC highlighted. Source: SEC Form 13F-HR filings, 2026-05-16. 2×2 strategic matrix plotting 16 entities by Reported book value ($B) (X) and Disclosed positions (Y), with a crosshair dividing the plot into four quadrants. Large & diversifiedSmall & diversifiedConcentrated giantSmall & concentrated $1B$1.2B$1.4B$1.6B$1.8B$2B$2.2B 05001,0001,500 Reported book value ($B) Disclosed positions Reported book value vs. disclosed position count
16 tracked 13F filers plotted by reported book value and disclosed position count; MARINER INVESTMENT GROUP LLC highlighted. Source: SEC Form 13F-HR filings, 2026-05-16.

How 13F filings are computed · All institutional filers · Largest filers by value

SEC Form 13F-HR filing desk

CIK 1096978 · Q4 2025 $1.7B book

BOOK-HEAVY · POS-FOCUS · CONC-HEAVY · LEAD-HEAVY · PHOTO-FINISH · TREND-FLAT · FY-SNAPSHOT

  • BOOK-HEAVY #44/360
  • POS-FOCUS 101 names
  • CONC-HEAVY 36% top-5
  • LEAD-HEAVY 9.7% top
  • PHOTO-FINISH Arvest Bank Trust Di…
  • TREND-FLAT Book steady
  • FY-SNAPSHOT Q4 2025

Photo-finish peer on reported book: Arvest Bank Trust Division

Read with: Institutional investor types - Manager type shapes what a 13F book represents — RIAs, hedge funds, and banks file the same form differently.

Reported-book neighbourhood · MARINER INVESTMENT GROUP LLC

Nearest tracked filers by aggregate 13F reported book, not a full corpus reprint.

Arvest Bank Trust Di… · near$1.7BMARINER INVESTMENT · this fi…$1.7BPine Valley Investme… · near$1.5BMaple , . · near$1.5BAsset Dedication, · near$1.5B
Aggregate reported 13F book value ($)
MARINER INVESTMENT GROUP LLC's largest reported positions
  1. 1
    MICROSOFT CORP $166.4M

    9.7% of book

  2. 2

    7.4% of book

  3. 3
    ALPHABET INC $109.8M

    6.4% of book

  4. 4

    6.3% of book

  5. 5

    6.2% of book

  6. 6
    CISCO SYS INC $105.7M

    6.2% of book

Top 6 of 101 positions by value · Q4 2025

How the reported book breaks down

$1.7B decomposed into the top 5 reported positions (shown below) versus every other disclosed position.

Top 5 positions: $616.6M (36.0%) Remaining 96 positions: $1.1B (64.0%)

Top Reported Holdings

# Security Value % of book
1 MICROSOFT CORP $166.4M 9.7%
2 LAM RESEARCH CORP $126.0M 7.4%
3 ALPHABET INC $109.8M 6.4%
4 COSTCO WHSL CORP NEW $107.8M 6.3%
5 ISHARES BITCOIN TRUST ETF $106.6M 6.2%
6 CISCO SYS INC $105.7M 6.2%
7 ASML HOLDING N V $99.5M 5.8%
8 TEXAS INSTRS INC $97.0M 5.7%
9 NVIDIA CORPORATION $92.7M 5.4%
10 LINDE PLC $85.3M 5.0%
11 INTEL CORP $81.2M 4.7%
12 HONEYWELL INTL INC $76.5M 4.5%
13 APPLE INC $67.4M 3.9%
14 MASTERCARD INCORPORATED $57.1M 3.3%
15 CINTAS CORP $50.6M 3.0%
16 MCDONALDS CORP $49.8M 2.9%
17 LOWES COS INC $24.4M 1.4%
18 ALIBABA GROUP HLDG LTD $23.3M 1.4%
19 FORD MTR CO $20.8M 1.2%
20 ISHARES TR $20.2M 1.2%
21 FLUOR CORP $17.2M 1.0%
22 NEXTERA ENERGY CAP HLDGS INC $12.4M 0.7%
23 ON SEMICONDUCTOR CORP $9.5M 0.6%
24 RITHM CAPITAL CORP $9.5M 0.6%
25 SHIFT4 PMTS INC $7.9M 0.5%

Latest Quarter Trades · Q4 2025

New positions (101)

Frequently Asked Questions

How big is MARINER INVESTMENT GROUP LLC's 13F portfolio?
MARINER INVESTMENT GROUP LLC reports $1.7B of long US-equity positions across 101 securities as of Q4 2025. This reflects 13F-disclosed holdings only, it is not the firm's total assets under management.
Where does MARINER INVESTMENT GROUP LLC sit among tracked 13F filers?
According to SEC Form 13F-HR filings in this corpus, MARINER INVESTMENT GROUP LLC ranks #44 of 360 institutional filers by reported book value (largest first), matching the /funds listing. The ordinal is recomputed live from filers with reported book value > 0. See /methodology/#corpus-placement.
What is MARINER INVESTMENT GROUP LLC's largest position?
MARINER INVESTMENT GROUP LLC's largest reported position is MICROSOFT CORP at $166.4M, about 9.7% of its reported book as of Q4 2025.
What did MARINER INVESTMENT GROUP LLC trade last quarter?
In its Q4 2025 filing, MARINER INVESTMENT GROUP LLC opened 101 new positions. Each change is drawn from a line in the firm's 13F-HR filing and can be verified on SEC EDGAR.

Nationwide filers with similar book size or holding count

Two 13F-derived peer sets for MARINER INVESTMENT GROUP LLC: nearest reported book value and nearest holding inventory, not catalog browse links.

Using this filing

  • The rankings sort every tracked filer the same way MARINER INVESTMENT GROUP LLC was placed above, so you can see exactly how the rest of the field compares. View the rankings
  • Arvest Bank Trust Division reported the nearest book value ($1.7B) this quarter, a useful scale comparison for MARINER INVESTMENT GROUP LLC. Compare filers
  • 13F-HR reports long US-listed equity positions only, not total AUM, short positions, or non-equity holdings, treat the reported book as a partial picture. Read the methodology

Form 13F-HR discloses long US-listed equity positions of managers with $100M+ qualifying assets, filed within 45 days of period end. Reported value is not total AUM.

Source: U.S. Securities and Exchange Commission (SEC) - EDGAR Form 13F-HR institutional holdings filings · Q4 2025 13F-HR discloses long US-listed equity positions of managers with $100M+ qualifying assets, filed within 45 days of period end. Reported value is not total AUM.

PlainFundData is rendered directly from SEC EDGAR Form 13F-HR institutional holdings filings, no number is typed in by an editor. Filer holdings, changes, and reported book on this page are aggregated live from those 13F-HR extracts. See our editorial standards & corrections policy, the methodology behind these numbers, or report a data error. Data current as of 2026-05-16.