401(k) · DOL Form 5500 · 2023

Diamond Offshore Management Company 401(k) Plan

Data updated 2026-08-11

$356M
Total assets: 1,183
Participants: 97th
Percentile by assets: $300,758
Avg per participant

Official DOL plan name: Diamond Offshore 401(k) Plan · Sponsored by Diamond Offshore Management Company · Texas · Mining & Oil Extraction

$356M in assets, 1,183 participants

Diamond Offshore Management Company's Diamond Offshore 401(k) Plan reported $356M in total assets and 1,183 participants in its 2023 DOL Form 5500 filing, ranking in the 97th 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.

97th percentile by assets (of 127,072 plans)
#757 in Mining & Oil Extraction (811 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, $356M for 1,183 participants (~$300,758/participant), up 11.4% in 2023.

$356M
total plan assets (2023 EOY): 1,183
covered participants: 97th
percentile by assets (of 127,072 plans): $300,758
avg assets per participant

Where Diamond Offshore 401(k) Plan sits by total assets

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

End-of-year total assets · plan year 2023 · DOL Form 5500

$355,796,435 Top 3% higher than 97% of 127,068 filed plans

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

Source U.S. Department of Labor Form 5500 filings (EBSA) · plan year 2023

Diamond Offshore 401(k) Plan reported net income rose from -$101M in the plan year 2022 filing to $36M in the plan year 2023 filing.
Diamond Offshore 401(k) Plan reported participants rose from 1,043 in the plan year 2022 filing to 1,183 in the plan year 2023 filing.
Diamond Offshore 401(k) Plan end-of-year assets rose from $319M in the plan year 2022 filing to $356M in the plan year 2023 filing.

See the national 2022→2023 release diff →

State

Texas

Industry

Mining & Oil Extraction

Diamond Offshore 401(k) Plan vs the 2023 asset distribution

By assets, Diamond Offshore 401(k) Plan outranks 97% of the 127,072 plans that filed a Form 5500 for the 2023 plan year, and holds roughly 3.6x the national average plan size of $100M (721 average participants).

Scale-class filing particulars (2023)

Total Assets (Beginning of Year)	$319M
Net Assets (End of Year)	$356M
Net Income	$36M
Employer EIN	133560049
Plan Effective Date	1989-07-01
Filing Status	FILING RECEIVED

Sponsor Plan History (Diamond Offshore Management Company)

Total plan assets by year, all Diamond Offshore Management Company plans on file

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

AT&T Retirement Savings Plan $40.0B · 119,854
Exxonmobil Savings Plan $21.9B · 23,477
Caterpillar 401(k) Savings Plan $16.5B · 41,679
American Airlines, Inc. 401(k) Plan $14.7B · 88,792
Dell Inc. 401(k) Plan $13.5B · 45,686

Compare Diamond Offshore 401(k) Plan side-by-side with 3 peers →

Similar-Sized 401(k) Plans Nationally

401(k) plans in other states closest to Diamond Offshore 401(k) Plan by total assets, not by location.

The Safe Harbor 401(k) Plan (NY) $356M · 1,940
Bendix Commercial Vehicle Systems LLC Savings Plan (OH) $356M · 2,445
Ag US Group Services Inc. Employee Retirement Plan (NY) $356M · 368
Proskauer Rose LLP Savings Plan for Staff and Partners (NY) $356M · 951

Frequently Asked Questions

How did Diamond Offshore 401(k) Plan assets move in 2023? ▼

Diamond Offshore 401(k) Plan grew at a solid clip - up 11.4% during 2023, from $319M to $356M. Reported net income was $36M.

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 97th percentile by end-of-year assets among 127,072 plans that reported assets for plan year 2023 (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 The Safe Harbor 401(k) Plan in NY ($356M, 1,940 participants).

Next read for Diamond Offshore 401(k) Plan

Scale reading

Ways to act on Diamond Offshore 401(k) Plan's numbers.

By total assets, Diamond Offshore 401(k) Plan ranks in the top 5% of all filed plans by assets. See the largest plans
Compare it side-by-side against 3 similar 401(k) plans in Texas. Compare plans
Diamond Offshore Management Company's sponsor-wide assets have grown 18.2% since 2022 across 3 plan years on file. More Mining & Oil Extraction plans

Source: U.S. Department of Labor, Employee Benefits Security Administration (EBSA), Form 5500 public disclosure dataset. Plan year 2023.

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