401(k) · DOL Form 5500 · 2024

Diamond Offshore Management Company 401(k) Plan

Data updated 2026-08-25

$377M
Total assets Above avg plan size
1,272
Participants Near avg headcount
96th
Percentile by assets National rank
$296,722
Avg per participant High balance/head
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Official DOL plan name: Diamond Offshore 401(k) Plan · Sponsored by Diamond Offshore Management Company · Texas · Mining & Oil Extraction

$377M in assets, 1,272 participants

Diamond Offshore Management Company's Diamond Offshore 401(k) Plan reported $377M in total assets and 1,272 participants in its 2024 DOL Form 5500 filing, ranking in the 96th percentile by assets among filed plans. Figures are as reported by the plan sponsor to the Department of Labor, not audited or endorsed by PlainRetire.

  • #732 in Mining & Oil Extraction (785 peers)

Where Diamond Offshore 401(k) Plan sits by assets

Diamond Offshore 401(k) Plan sits in the top 5% of all filed plans by assets, $377M for 1,272 participants (~$296,722/participant), up 6.1% in 2024.

#732
in Mining & Oil Extraction (785 peers)
+6.1%
assets growth YoY
3.8×
vs typical plan assets (national mean)

Diamond Offshore 401(k) Plan's outsized position by total assets

Diamond Offshore 401(k) Plan vs every filed plan by assets

End-of-year total assets · plan year 2024 · DOL Form 5500

$377,430,996 Top 4% higher than 96% of 123,620 filed plans

This plan $0 $2,050,000,000 every filed plan with reported assets, bucketed by value

Dashed line + filled bar = this entry, among filed plans.

Source U.S. Department of Labor Form 5500 filings (EBSA) · plan year 2024

Diamond Offshore 401(k) Plan's large-plan peer group by participant headcount

Plan-year 2024 Form 5500 filings with a reported participant count, partitioned by headcount band, not by assets. Diamond Offshore 401(k) Plan lands in the large band (1,272 participants).

What changed between DOL Form 5500 filings

plan year 2023 → plan year 2024

  • Diamond Offshore 401(k) Plan reported net income fell from $36M in the plan year 2023 filing to $22M in the plan year 2024 filing.
  • Diamond Offshore 401(k) Plan reported participants rose from 1,183 in the plan year 2023 filing to 1,272 in the plan year 2024 filing.
  • Diamond Offshore 401(k) Plan end-of-year assets rose from $356M in the plan year 2023 filing to $377M in the plan year 2024 filing.

See the national 2023→2024 release diff →

Plan-year Form 5500 strip

Filing strip 133560049 · Diamond Offshore Management Company PY 2024 · 401(k)

Diamond Offshore 401(k) Plan · $377M · 1,272 · 96th

  • EIN $377M
  • EIN 1,272
  • EIN 96th
  • EIN 401(k)
  • EIN near Iuoe Local 478 Annuity Fund
  • EIN ind #732

Stamps derive from this plan's Form 5500 line items (assets, participants, type, EIN, cohort placement) - not a quality rating of the sponsor. Read with Mining & Oil Extraction retirement plans → · Plans in Texas →

Diamond Offshore 401(k) Plan in the asset neighbourhood

The Middleby Corporation Profit Sharing PlanThe Middleby Corporation Pro…$378MFaith Technologies Incorporated 401(k) Retirement PlanFaith Technologies Incorpora…$378MEmblemhealth Services Company, LLC 401(k) PlanEmblemhealth Services Compan…$378MDiamond Offshore 401(k) Plan$377MIuoe Local 478 Annuity Fund$377M
End-of-year total assets ($M) among Diamond Offshore 401(k) Plan and nearest nationwide 401(k) peers. Source: DOL Form 5500 plan year 2024.

Scale-class filing particulars (2024)

Total Assets (Beginning of Year)$356M
Net Assets (End of Year)$377M
Net Income$22M
Employer EIN133560049
Plan Effective Date1989-07-01
Filing StatusFILING RECEIVED

Sponsor Plan History (Diamond Offshore Management Company)

Sponsor-wide plan assets over time

All Diamond Offshore Management Company plans reported in each filing year

Latest sponsor-wide plan assets
$377M 18.17211394381709% vs 2022
2024 filing year
$300M$320M$340M$360M$380M$400M 202220232024 $319M $377M ▲ +18.2%
Year Plans Participants Total Assets
2022 1 1,043 $319M
2023 1 1,183 $356M
2024 1 1,272 $377M

Nearby 401(k) Plans in Texas

Peer 401(k) plans, same state, same plan type, ranked by total assets.

Diamond Offshore 401(k) Plan vs. nearby 401(k) plans in Texas, assets vs. participants Scatter plot of 6 data points. -50000050000100000150000 -1001020304050 Total assets ($B) Participants Diamond Offshore 401(k) Plan, Total assets ($B): 0.377430996 · Participants: 1272Diamond Offshore 401(k) PlanAT&T Retirement Savings Plan, Total assets ($B): 43.121795 · Participants: 109889AT&T Retirement Savings PlanExxonmobil Savings Plan, Total assets ($B): 23.711 · Participants: 21990Exxonmobil Savings PlanChevron Employee Savings Investment Plan, Total assets ($B): 20.378704663 · Participants: 21505Chevron Employee Savings Investment PlanCaterpillar 401(k) Savings Plan, Total assets ($B): 18.81200478 · Participants: 43873Caterpillar 401(k) Savings PlanSouthwest Airlines Co. Retirement Savings Plan, Total assets ($B): 16.991748637 · Participants: 67820Southwest Airlines Co. Retirement Savings Plan
Diamond Offshore 401(k) Plan vs. nearby 401(k) plans in Texas, assets vs. participants
Compare Diamond Offshore 401(k) Plan side-by-side with 3 peers →

Diamond Offshore 401(k) Plan's out-of-state 401(k) peers by assets and headcount

Outside Texas, the nearest 401(k) by assets is Iuoe Local 478 Annuity Fund in CT ($377M); by covered participants it is Gibson Brands, Inc. 401(k) Plan in TN (1,272 participants). Same-state nearby plans are listed separately above.

Closest by plan assets

Nearest other-state filings by tot_assets_eoy ($377M here).

Similar participant headcount

Nearest other-state filings by covered participants (1,272 participants); asset peers above are excluded.

DOL Form 5500 plan year 2024. Asset totals can differ widely at the same headcount; neither axis is a quality rating.

Frequently Asked Questions

How did Diamond Offshore 401(k) Plan assets move in 2024? ▼
Diamond Offshore 401(k) Plan grew at a solid clip - up 6.1% during 2024, from $356M to $377M. Reported net income was $22M.
How have Diamond Offshore Management Company plan assets changed over time? ▼
Across 3 plan years on file (2022-2024), Diamond Offshore Management Company's sponsor-wide assets grew 18.2%, from $319M to $377M.
Where does Diamond Offshore 401(k) Plan rank by assets among Form 5500 filers? ▼
Diamond Offshore 401(k) Plan ranks in the 96th percentile by end-of-year assets among 123,622 plans that reported assets for plan year 2024 (in the top 5% of all filed plans by assets).
Which 401(k) plans are similar in size to Diamond Offshore 401(k) Plan? ▼
Among 401(k) plans in other states, the closest by assets is Iuoe Local 478 Annuity Fund in CT ($377M, 4,899 participants).
Which 401(k) plans cover a similar participant headcount to Diamond Offshore 401(k) Plan? ▼
Among 401(k) plans in other states, the closest by covered participants is Gibson Brands, Inc. 401(k) Plan in TN (1,272 participants, $54M in assets).

Source: U.S. Department of Labor, Employee Benefits Security Administration (EBSA), Form 5500 public disclosure dataset. Plan year 2024.

Source: DOL EFAST2 filing system (efast.dol.gov) - original filing retrieval by EIN 133560049.

Read our methodology - how this data is sourced, computed, and verified.

Data sourced from U.S. Department of Labor Form 5500 filings (EBSA). See our methodology for details.