401(k) · DOL Form 5500 · 2022

Mp Mine Operations LLC Dba Mp Materials 401(k) Plan

Data updated 2026-08-25

$7M
Total assets Small plan by assets
340
Participants Below avg headcount
57th
Percentile by assets National rank
$20,500
Avg per participant Low balance/head
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Official DOL plan name: Mp Materials 401(k) Plan · Sponsored by Mp Mine Operations LLC Dba Mp Materials · California · Mining & Oil Extraction

$7M in assets, 340 participants

Mp Mine Operations LLC Dba Mp Materials's Mp Materials 401(k) Plan reported $7M in total assets and 340 participants in its 2022 DOL Form 5500 filing, ranking in the 57th 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.

  • #346 in Mining & Oil Extraction (892 peers)

Mp Mine Operations LLC Dba Mp Materials multi-year trail

Mp Mine Operations LLC Dba Mp Materials's plans moved +234.4% in assets from 2022 to 2024; this filing shows Mp Materials 401(k) Plan at $7M / 340 participants.

#346
in Mining & Oil Extraction (892 peers)
+24.5%
assets growth YoY

Mp Materials 401(k) Plan's mid-pack asset rank among Mining & Oil Extraction and all filers

Mp Materials 401(k) Plan vs every filed plan by assets

End-of-year total assets · plan year 2022 · DOL Form 5500

$6,970,139 Top 43% higher than 57% of 139,123 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 2022

Mp Materials 401(k) Plan among mid-size filed plans by headcount

Plan-year 2022 Form 5500 filings with a reported participant count, partitioned by headcount band, not by assets. Mp Materials 401(k) Plan sits mid-pack in the medium band (340 participants).

Plan-year Form 5500 strip

Filing strip 844465489 · Mp Mine Operations LLC Dba Mp Materials PY 2022 · 401(k)

Mp Materials 401(k) Plan · $7M · 340 · 57th

  • VS-ST $7M
  • BOY 340
  • SCH 57th
  • EBSA 401(k)
  • PART near Neal Mast & Son Greenhouses, Inc. 401(k) Plan
  • TYPE ind #346

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 California →

Mp Materials 401(k) Plan in the asset neighbourhood

Mp Materials 401(k) Plan$7MNeal Mast & Son Greenhouses, Inc. 401(k) PlanNeal Mast & Son Greenhouses,…$7MSaturn of St. Paul Salary Deferral 401(k) Profit Sharing PlanSaturn of St. Paul Salary De…$7MHelical Drilling 401(k) Profit Sharing PlanHelical Drilling 401(k) Prof…$7MHodgdon Powder Co., Inc. 401(k) PlanHodgdon Powder Co., Inc. 401…$7M
End-of-year total assets ($M) among Mp Materials 401(k) Plan and nearest nationwide 401(k) peers. Source: DOL Form 5500 plan year 2022.

Mp Mine Operations LLC Dba Mp Materials multi-year asset trail

Sponsor-wide plan assets over time

All Mp Mine Operations LLC Dba Mp Materials plans reported in each filing year

Latest sponsor-wide plan assets
$23M 234.39605723788293% vs 2022
2024 filing year
$5M$10M$15M$20M$25M 202220232024 $6.97M $23.3M ▲ +234.4%
Year Plans Participants Total Assets
2022 1 340 $7M
2023 1 485 $14M
2024 1 683 $23M

Mp Mine Operations LLC Dba Mp Materials filing trail (2022)

Total Assets (Beginning of Year)$6M
Net Assets (End of Year)$7M
Net Income$1M
Employer EIN844465489
Plan Effective Date2018-05-01
Filing StatusFILING RECEIVED

Nearby 401(k) Plans in California

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

Mp Materials 401(k) Plan vs. nearby 401(k) plans in California, assets vs. participants Scatter plot of 6 data points. -50000050000100000150000200000250000 -200204060 Total assets ($B) Participants Mp Materials 401(k) Plan, Total assets ($B): 0.006970139 · Participants: 340Mp Materials 401(k) PlanWells Fargo & Company 401(k) Plan, Total assets ($B): 45.765616608 · Participants: 205865Wells Fargo & Company 401(k) PlanGoogle LLC 401(k) Savings Plan, Total assets ($B): 28.89820221 · Participants: 102963Google LLC 401(k) Savings PlanOracle Corporation 401(k) Savings and Investment Plan, Total assets ($B): 21.851716605 · Participants: 46320Oracle Corporation 401(k) Savings and Investment PlanChevron Employee Savings Investment Plan, Total assets ($B): 18.60989746 · Participants: 19946Chevron Employee Savings Investment PlanIntel 401(k) Savings Plan, Total assets ($B): 18.361585903 · Participants: 54672Intel 401(k) Savings Plan
Mp Materials 401(k) Plan vs. nearby 401(k) plans in California, assets vs. participants
Compare Mp Materials 401(k) Plan side-by-side with 3 peers →

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

Outside California, the nearest 401(k) by assets is Neal Mast & Son Greenhouses, Inc. 401(k) Plan in MI ($7M); by covered participants it is T.C.T. 401(k) Profit Sharing Plan in WA (340 participants). Same-state nearby plans are listed separately above.

Similar participant headcount

Nearest other-state filings by covered participants (340 participants); asset peers above are excluded.

DOL Form 5500 plan year 2022. Asset totals can differ widely at the same headcount; neither axis is a quality rating.

Frequently Asked Questions

How did Mp Materials 401(k) Plan assets move in 2022? ▼
Mp Materials 401(k) Plan grew sharply - up 24.5% during 2022, from $6M to $7M. Reported net income was $1M.
How have Mp Mine Operations LLC Dba Mp Materials plan assets changed over time? ▼
Across 3 plan years on file (2022-2024), Mp Mine Operations LLC Dba Mp Materials's sponsor-wide assets grew 234.4%, from $7M to $23M.
Which 401(k) plans are similar in size to Mp Materials 401(k) Plan? ▼
Among 401(k) plans in other states, the closest by assets is Neal Mast & Son Greenhouses, Inc. 401(k) Plan in MI ($7M, 126 participants).
Which 401(k) plans cover a similar participant headcount to Mp Materials 401(k) Plan? ▼
Among 401(k) plans in other states, the closest by covered participants is T.C.T. 401(k) Profit Sharing Plan in WA (340 participants, $9M in assets).

Source: U.S. Department of Labor, Employee Benefits Security Administration (EBSA), Form 5500 public disclosure dataset. Plan year 2022.

Source: DOL EFAST2 filing system (efast.dol.gov) - original filing retrieval by EIN 844465489.

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.