401(k) · DOL Form 5500 · 2022

Alexion Pharmaceuticals, Inc. 401(k) Plan

Data updated 2026-08-11

$462M
Total assets: 2,372
Participants: 98th
Percentile by assets: $194,934
Avg per participant

Official DOL plan name: Alexion 401(k) Plan · Sponsored by Alexion Pharmaceuticals, Inc. · Massachusetts · Professional & Technical Services

$462M in assets, 2,372 participants

Alexion Pharmaceuticals, Inc.'s Alexion 401(k) Plan reported $462M in total assets and 2,372 participants in its 2022 DOL Form 5500 filing, ranking in the 98th 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.

98th percentile by assets (of 139,126 plans)
#21,236 in Professional & Technical Services (21,562 peers)

Coverage in Massachusetts

Alexion 401(k) Plan covers 2,372 participants in Massachusetts, 3.6x the typical Massachusetts plan (state average ~659 per filing). Assets: $462M.

$462M
total plan assets (2022 EOY): 2,372
covered participants: 98th
percentile by assets (of 139,126 plans): $194,934
avg assets per participant

The plan reported a net loss of $50M for the year, a single-year figure driven by markets and benefit payments, not a measure of plan health.

State

Massachusetts

Industry

Professional & Technical Services

Participants vs Massachusetts filers

In Massachusetts, the average filing covers about 659 participants across 4,265 plans. Alexion 401(k) Plan reports 2,372 participants - 3.6x that state average ($462M EOY assets).

Massachusetts filing particulars

Total Assets (Beginning of Year)	$513M
Net Assets (End of Year)	$462M
Net Income	-$50M
Employer EIN	854136092
Plan Effective Date	1993-08-01
Filing Status	FILING RECEIVED

Sponsor Plan History (Alexion Pharmaceuticals, Inc.)

Total plan assets by year, all Alexion Pharmaceuticals, Inc. plans on file

Year	Plans	Participants	Total Assets
2022	1	2,372	$462M
2023	1	2,509	N/A

Nearby 401(k) Plans in Massachusetts

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

Alexion 401(k) Plan vs. nearby 401(k) plans in Massachusetts, assets vs. participants

Fidelity Retirement Savings Plan $23.0B · 52,036
Liberty Mutual 401(k) Plan $8.8B · 32,843
Massachusetts Institute of Technology Supplemental 401(k) Plan $5.8B · 13,690
Philips North America 401(k) Plan $5.2B · 19,750
Boston Scientific Corporation 401(k) Retirement Savings Plan $4.9B · 18,359

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

Similar-Sized 401(k) Plans Nationally

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

Mccarthy Employee Retirement Savings Plan (MO) $462M · 4,297
Plexus Corp. 401(k) Retirement Plan (WI) $463M · 3,363
Epic Games, Inc. 401(k) Plan and Trust (NC) $463M · 2,255
South State Bank 401(k) Retirement Savings Plan (FL) $463M · 5,123

Frequently Asked Questions

How did Alexion 401(k) Plan assets move in 2022? ▼

Alexion 401(k) Plan pulled back noticeably - down 9.8% during 2022, from $513M to $462M. Reported net income was -$50M.

Where does Alexion 401(k) Plan rank by assets among Form 5500 filers? ▼

Alexion 401(k) Plan ranks in the 98th percentile by end-of-year assets among 139,126 plans that reported assets for plan year 2022 (in the top 5% of all filed plans by assets).

Which 401(k) plans are similar in size to Alexion 401(k) Plan? ▼

Among 401(k) plans in other states, the closest by assets is Mccarthy Employee Retirement Savings Plan in MO ($462M, 4,297 participants).

Next read for Alexion 401(k) Plan

Filing takeaways

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

By total assets, Alexion 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 Massachusetts. Compare plans

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 854136092.