Civic Intelligence

Biogen Idec Inc.

Plan context: Biogen 401(K) Savings Plan

EIN 33-0112644 • Cambridge, MA • 71 filings • 11 plans

14 Cambridge CenterCambridge, MA 02142
Current Snapshot

Latest Year

2024

2024 Participants

4,289

2024 Assets

$2,159,190,583

2024 Contributions

$133,361,240

Historical Graphs

Total Assets Over Time

Aggregate end-of-year assets by filing year, excluding zero-asset years

$2,159,190,583$1,079,595,292$0200120132024YearValue
$2,159,190,583Latest year 2024

Participants Over Time

Largest reported end-of-year plan headcount by filing year, used to avoid double-counting participants across overlapping plans

5,7022,8510200020122024YearValue
4,289Latest year 2024

Company Timeline

Year summaries and individual filings are combined here so you can stay in one place while moving across years and plan filings.

Year / FilingFilingsParticipantsAssetsContributionsContrib./Participant
202434,289$2,159,190,583$133,361,240$31,094iApproximate average salary by contribution assumption: employee only about $777,345 at 4% or $518,230 at 6%; with 50% employer match about $518,230 at 4% or $345,486 at 6%; with 100% employer match about $388,672 at 4% or $259,115 at 6%.
Biogen 401(K) Savings Plan-4,289$2,159,190,583$133,361,240$31,094iApproximate average salary by contribution assumption: employee only about $777,345 at 4% or $518,230 at 6%; with 50% employer match about $518,230 at 4% or $345,486 at 6%; with 100% employer match about $388,672 at 4% or $259,115 at 6%.
Biogen Idec Health and Welfare Benefit Plan-4,266---
U.S. Change in Control Severance Plan-4,160---
202334,292$1,938,085,017$143,529,507$33,441iApproximate average salary by contribution assumption: employee only about $836,029 at 4% or $557,353 at 6%; with 50% employer match about $557,353 at 4% or $371,569 at 6%; with 100% employer match about $418,015 at 4% or $278,676 at 6%.
Biogen 401(K) Savings Plan-4,292$1,938,085,017$143,529,507$33,441iApproximate average salary by contribution assumption: employee only about $836,029 at 4% or $557,353 at 6%; with 50% employer match about $557,353 at 4% or $371,569 at 6%; with 100% employer match about $418,015 at 4% or $278,676 at 6%.
Biogen Idec Health and Welfare Benefit Plan-4,161---
U.S. Change in Control Severance Plan-4,062---
202235,011$1,601,252,778$150,133,669$29,961iApproximate average salary by contribution assumption: employee only about $749,020 at 4% or $499,347 at 6%; with 50% employer match about $499,347 at 4% or $332,898 at 6%; with 100% employer match about $374,510 at 4% or $249,673 at 6%.
Biogen 401(K) Savings Plan-5,003$1,601,252,778$150,133,669$30,009iApproximate average salary by contribution assumption: employee only about $750,218 at 4% or $500,145 at 6%; with 50% employer match about $500,145 at 4% or $333,430 at 6%; with 100% employer match about $375,109 at 4% or $250,073 at 6%.
Biogen Idec Health and Welfare Benefit Plan-5,011---
U.S. Change in Control Severance Plan-4,869---
202135,655$2,009,098,193$160,025,878$28,298iApproximate average salary by contribution assumption: employee only about $707,453 at 4% or $471,635 at 6%; with 50% employer match about $471,635 at 4% or $314,424 at 6%; with 100% employer match about $353,727 at 4% or $235,818 at 6%.
Biogen 401(K) Savings Plan-5,611$2,009,098,193$160,025,878$28,520iApproximate average salary by contribution assumption: employee only about $713,001 at 4% or $475,334 at 6%; with 50% employer match about $475,334 at 4% or $316,889 at 6%; with 100% employer match about $356,500 at 4% or $237,667 at 6%.
Biogen Idec Health and Welfare Benefit Plan-5,655---
U.S. Change in Control Severance Plan-5,544---
202035,702$1,702,688,045$151,121,462$26,503iApproximate average salary by contribution assumption: employee only about $662,581 at 4% or $441,721 at 6%; with 50% employer match about $441,721 at 4% or $294,480 at 6%; with 100% employer match about $331,290 at 4% or $220,860 at 6%.
Biogen 401(K) Savings Plan-5,702$1,702,688,045$151,121,462$26,503iApproximate average salary by contribution assumption: employee only about $662,581 at 4% or $441,721 at 6%; with 50% employer match about $441,721 at 4% or $294,480 at 6%; with 100% employer match about $331,290 at 4% or $220,860 at 6%.
Biogen Idec Health and Welfare Benefit Plan-5,698---
U.S. Change in Control Severance Plan-5,588---
201934,721$1,345,969,819$113,812,395$24,108iApproximate average salary by contribution assumption: employee only about $602,692 at 4% or $401,795 at 6%; with 50% employer match about $401,795 at 4% or $267,863 at 6%; with 100% employer match about $301,346 at 4% or $200,897 at 6%.
Biogen 401(K) Savings Plan-4,721$1,345,969,819$113,812,395$24,108iApproximate average salary by contribution assumption: employee only about $602,692 at 4% or $401,795 at 6%; with 50% employer match about $401,795 at 4% or $267,863 at 6%; with 100% employer match about $301,346 at 4% or $200,897 at 6%.
Biogen Idec Health and Welfare Benefit Plan-4,677---
U.S. Change in Control Severance Plan-4,494---
201834,579$1,047,151,376$107,227,215$23,417iApproximate average salary by contribution assumption: employee only about $585,429 at 4% or $390,286 at 6%; with 50% employer match about $390,286 at 4% or $260,191 at 6%; with 100% employer match about $292,715 at 4% or $195,143 at 6%.
Biogen 401(K) Savings Plan-4,513$1,047,151,376$107,227,215$23,760iApproximate average salary by contribution assumption: employee only about $593,991 at 4% or $395,994 at 6%; with 50% employer match about $395,994 at 4% or $263,996 at 6%; with 100% employer match about $296,995 at 4% or $197,997 at 6%.
U.S. Change in Control Severance Plan-4,397---
Biogen Idec Health and Welfare Benefit Plan-4,579---
201734,478$1,108,141,263$104,496,730$23,336iApproximate average salary by contribution assumption: employee only about $583,390 at 4% or $388,926 at 6%; with 50% employer match about $388,926 at 4% or $259,284 at 6%; with 100% employer match about $291,695 at 4% or $194,463 at 6%.
Biogen 401(K) Savings Plan-4,440$1,108,141,263$104,496,730$23,535iApproximate average salary by contribution assumption: employee only about $588,382 at 4% or $392,255 at 6%; with 50% employer match about $392,255 at 4% or $261,503 at 6%; with 100% employer match about $294,191 at 4% or $196,127 at 6%.
Biogen Idec Health and Welfare Benefit Plan-4,478---
U.S. Change in Control Severance Plan-4,310---
201634,687$939,985,258$103,126,813$22,003iApproximate average salary by contribution assumption: employee only about $550,068 at 4% or $366,712 at 6%; with 50% employer match about $366,712 at 4% or $244,475 at 6%; with 100% employer match about $275,034 at 4% or $183,356 at 6%.
Biogen 401(K) Savings Plan-4,604$939,985,258$103,126,813$22,399iApproximate average salary by contribution assumption: employee only about $559,985 at 4% or $373,323 at 6%; with 50% employer match about $373,323 at 4% or $248,882 at 6%; with 100% employer match about $279,992 at 4% or $186,662 at 6%.
Biogen Idec Health and Welfare Benefit Plan-4,687---
U.S. Change in Control Severance Plan-4,623---
201534,752$872,949,575$119,911,704$25,234iApproximate average salary by contribution assumption: employee only about $630,849 at 4% or $420,566 at 6%; with 50% employer match about $420,566 at 4% or $280,377 at 6%; with 100% employer match about $315,424 at 4% or $210,283 at 6%.
Biogen 401(K) Savings Plan-4,707$872,949,575$119,911,704$25,475iApproximate average salary by contribution assumption: employee only about $636,880 at 4% or $424,586 at 6%; with 50% employer match about $424,586 at 4% or $283,058 at 6%; with 100% employer match about $318,440 at 4% or $212,293 at 6%.
Biogen Idec Health and Welfare Benefit Plan-4,752---
U.S. Change in Control Severance Plan-4,540---
201434,994$823,853,859$103,829,170$20,791iApproximate average salary by contribution assumption: employee only about $519,770 at 4% or $346,513 at 6%; with 50% employer match about $346,513 at 4% or $231,009 at 6%; with 100% employer match about $259,885 at 4% or $173,257 at 6%.
Biogen 401(K) Savings Plan-4,994$823,853,859$103,829,170$20,791iApproximate average salary by contribution assumption: employee only about $519,770 at 4% or $346,513 at 6%; with 50% employer match about $346,513 at 4% or $231,009 at 6%; with 100% employer match about $259,885 at 4% or $173,257 at 6%.
Biogen Idec Health and Welfare Benefit Plan-4,947---
U.S. Change in Control Severance Plan-4,831---
201334,558$715,527,510$91,275,926$20,025iApproximate average salary by contribution assumption: employee only about $500,636 at 4% or $333,757 at 6%; with 50% employer match about $333,757 at 4% or $222,505 at 6%; with 100% employer match about $250,318 at 4% or $166,879 at 6%.
Biogen 401(K) Savings Plan-4,558$715,527,510$91,275,926$20,025iApproximate average salary by contribution assumption: employee only about $500,636 at 4% or $333,757 at 6%; with 50% employer match about $333,757 at 4% or $222,505 at 6%; with 100% employer match about $250,318 at 4% or $166,879 at 6%.
U.S. Change in Control Severance Plan-3,563---
Biogen Idec Health and Welfare Benefit Plan-4,293---
201234,079$529,745,326$75,827,006$18,590iApproximate average salary by contribution assumption: employee only about $464,740 at 4% or $309,827 at 6%; with 50% employer match about $309,827 at 4% or $206,551 at 6%; with 100% employer match about $232,370 at 4% or $154,913 at 6%.
Biogen 401(K) Savings Plan-4,079$529,745,326$75,827,006$18,590iApproximate average salary by contribution assumption: employee only about $464,740 at 4% or $309,827 at 6%; with 50% employer match about $309,827 at 4% or $206,551 at 6%; with 100% employer match about $232,370 at 4% or $154,913 at 6%.
Biogen Idec Health and Welfare Benefit Plan-3,972---
U.S. Change in Control Severance Plan-3,972---
201133,431$439,829,719$61,731,079$17,992iApproximate average salary by contribution assumption: employee only about $449,804 at 4% or $299,869 at 6%; with 50% employer match about $299,869 at 4% or $199,913 at 6%; with 100% employer match about $224,902 at 4% or $149,935 at 6%.
Biogen 401(K) Savings Plan-3,431$439,829,719$61,731,079$17,992iApproximate average salary by contribution assumption: employee only about $449,804 at 4% or $299,869 at 6%; with 50% employer match about $299,869 at 4% or $199,913 at 6%; with 100% employer match about $224,902 at 4% or $149,935 at 6%.
Biogen Idec Health and Welfare Benefit Plan-3,405---
U.S. Change in Control Severance Plan-3,405---
201033,633$451,567,704$63,533,917$17,488iApproximate average salary by contribution assumption: employee only about $437,200 at 4% or $291,467 at 6%; with 50% employer match about $291,467 at 4% or $194,311 at 6%; with 100% employer match about $218,600 at 4% or $145,733 at 6%.
Biogen 401(K) Savings Plan-3,614$451,567,704$63,533,917$17,580iApproximate average salary by contribution assumption: employee only about $439,499 at 4% or $292,999 at 6%; with 50% employer match about $292,999 at 4% or $195,333 at 6%; with 100% employer match about $219,749 at 4% or $146,500 at 6%.
Biogen Idec Health and Welfare Benefit Plan-3,633---
U.S. Change in Control Severance Plan-3,633---
200923,599$355,070,022$57,864,448$16,078iApproximate average salary by contribution assumption: employee only about $401,948 at 4% or $267,965 at 6%; with 50% employer match about $267,965 at 4% or $178,644 at 6%; with 100% employer match about $200,974 at 4% or $133,983 at 6%.
Biogen 401(K) Savings Plan-3,599$355,070,022$57,864,448$16,078iApproximate average salary by contribution assumption: employee only about $401,948 at 4% or $267,965 at 6%; with 50% employer match about $267,965 at 4% or $178,644 at 6%; with 100% employer match about $200,974 at 4% or $133,983 at 6%.
Biogen Idec Health and Welfare Benefit Plan-3,563---
200823,534$237,414,867$54,196,868$15,336iApproximate average salary by contribution assumption: employee only about $383,396 at 4% or $255,597 at 6%; with 50% employer match about $255,597 at 4% or $170,398 at 6%; with 100% employer match about $191,698 at 4% or $127,799 at 6%.
Biogen 401(K) Savings Plan-3,534$237,414,867$54,196,868$15,336iApproximate average salary by contribution assumption: employee only about $383,396 at 4% or $255,597 at 6%; with 50% employer match about $255,597 at 4% or $170,398 at 6%; with 100% employer match about $191,698 at 4% or $127,799 at 6%.
Biogen Idec Health and Welfare Benefit Plan-3,338---
200723,410$317,810,802$49,219,532$14,434iApproximate average salary by contribution assumption: employee only about $360,847 at 4% or $240,565 at 6%; with 50% employer match about $240,565 at 4% or $160,376 at 6%; with 100% employer match about $180,424 at 4% or $120,282 at 6%.
Biogen 401(K) Savings Plan-3,381$317,810,802$49,219,532$14,558iApproximate average salary by contribution assumption: employee only about $363,942 at 4% or $242,628 at 6%; with 50% employer match about $242,628 at 4% or $161,752 at 6%; with 100% employer match about $181,971 at 4% or $121,314 at 6%.
Biogen Idec Health and Welfare Benefit Plan-3,410---
200623,845$265,217,341$38,440,351$9,997iApproximate average salary by contribution assumption: employee only about $249,937 at 4% or $166,625 at 6%; with 50% employer match about $166,625 at 4% or $111,083 at 6%; with 100% employer match about $124,969 at 4% or $83,312 at 6%.
Biogen 401(K) Savings Plan-3,107$265,217,341$38,440,351$12,372iApproximate average salary by contribution assumption: employee only about $309,304 at 4% or $206,203 at 6%; with 50% employer match about $206,203 at 4% or $137,469 at 6%; with 100% employer match about $154,652 at 4% or $103,101 at 6%.
Biogen Idec Health and Welfare Benefit Plan-3,845---
200523,434$223,328,146$45,743,976$13,321iApproximate average salary by contribution assumption: employee only about $333,023 at 4% or $222,015 at 6%; with 50% employer match about $222,015 at 4% or $148,010 at 6%; with 100% employer match about $166,511 at 4% or $111,008 at 6%.
Biogen 401(K) Savings Plan-2,870$223,328,146$45,743,976$15,939iApproximate average salary by contribution assumption: employee only about $398,467 at 4% or $265,644 at 6%; with 50% employer match about $265,644 at 4% or $177,096 at 6%; with 100% employer match about $199,233 at 4% or $132,822 at 6%.
Biogen Idec Health and Welfare Benefit Plan-3,434---
200423,770$187,383,073$59,438,348$15,766iApproximate average salary by contribution assumption: employee only about $394,154 at 4% or $262,769 at 6%; with 50% employer match about $262,769 at 4% or $175,179 at 6%; with 100% employer match about $197,077 at 4% or $131,385 at 6%.
Biogen 401(K) Savings Plan-3,770$187,383,073$59,438,348$15,766iApproximate average salary by contribution assumption: employee only about $394,154 at 4% or $262,769 at 6%; with 50% employer match about $262,769 at 4% or $175,179 at 6%; with 100% employer match about $197,077 at 4% or $131,385 at 6%.
Biogen Idec Health and Welfare Benefit Plan-2,171---
200341,057$118,382,688$8,369,100$7,918iApproximate average salary by contribution assumption: employee only about $197,945 at 4% or $131,963 at 6%; with 50% employer match about $131,963 at 4% or $87,975 at 6%; with 100% employer match about $98,972 at 4% or $65,982 at 6%.
Biogen 401(K) Savings Plan-1,024$118,382,688$8,369,100$8,173iApproximate average salary by contribution assumption: employee only about $204,324 at 4% or $136,216 at 6%; with 50% employer match about $136,216 at 4% or $90,811 at 6%; with 100% employer match about $102,162 at 4% or $68,108 at 6%.
Biogen Idec Health and Welfare Benefit Plan-1,057---
IDEC PHARMACEUTICALS CORPORATION LONG TERM DISABILITY PLAN-0---
IDEC FLEXIBLE BENEFIT PLAN-0---
20024991$18,706,414$6,867,917$6,930iApproximate average salary by contribution assumption: employee only about $173,257 at 4% or $115,505 at 6%; with 50% employer match about $115,505 at 4% or $77,003 at 6%; with 100% employer match about $86,629 at 4% or $57,752 at 6%.
Biogen 401(K) Savings Plan-864$18,706,414$6,867,917$7,949iApproximate average salary by contribution assumption: employee only about $198,724 at 4% or $132,483 at 6%; with 50% employer match about $132,483 at 4% or $88,322 at 6%; with 100% employer match about $99,362 at 4% or $66,241 at 6%.
IDEC FLEXIBLE BENEFIT PLAN-933---
Biogen Idec Health and Welfare Benefit Plan-991---
IDEC PHARMACEUTICALS CORPORATION LONG TERM DISABILITY PLAN-943---
20013676$16,729,766$4,494,081$6,648iApproximate average salary by contribution assumption: employee only about $166,201 at 4% or $110,801 at 6%; with 50% employer match about $110,801 at 4% or $73,867 at 6%; with 100% employer match about $83,101 at 4% or $55,400 at 6%.
Biogen 401(K) Savings Plan-568$16,729,766$4,494,081$7,912iApproximate average salary by contribution assumption: employee only about $197,803 at 4% or $131,869 at 6%; with 50% employer match about $131,869 at 4% or $87,912 at 6%; with 100% employer match about $98,901 at 4% or $65,934 at 6%.
Biogen Idec Health and Welfare Benefit Plan-676---
IDEC PHARMACEUTICALS CORPORATION LONG TERM DISABILITY PLAN-640---
20003460$0$0-
Biogen 401(K) Savings Plan-422---
IDEC PHARMACEUTICALS CORPORATION LONG TERM DISABILITY PLAN-459---
Biogen Idec Health and Welfare Benefit Plan-460---