NASDAQ:BIIB | Stock Price History | BIOGEN INC.

Complete retained daily price history on its own workbook tab. Split-adjusted close keeps every historical share price on one comparable split basis. Cumulative dividend-reinvested close is the daily close of a rebased total-return index: it starts with one share at the earliest retained close, reinvests every distribution, and normalizes every forward and reverse split exactly once. Admitted exchange opening prices remain a distinct current-session series.

Available history
1991-09-17 to 2026-09-04
Data captured

Stock Price Chart

Blue: Split-adjusted close · Orange: Cumulative dividend-reinvested close

$0.34$1.42$6.01$25.38$107.26$453.211991-09-172026-08-27

Logarithmic scale. Both lines share the same starting value for the selected range.

Historical Stock Price

DateSplit-adjusted closeCumulative dividend-reinvested closeReported volumeOpen priceExchange Volume
2026-09-04$222.1820,024
2026-09-03$224.7131,770
2026-09-02$218.23110,718
2026-09-01$217.6132,387
2026-08-31$215.9024,798
2026-08-28$220.6520,024
2026-08-27$221.50$221.50497,300$218.2425,974
2026-08-26$221.07$221.07647,200$221.4030,593
2026-08-25$220.77$220.77495,400$218.1713,783
2026-08-24$218.12$218.12649,800$217.0040,144
2026-08-21$216.78$216.78722,300$217.0032,225
2026-08-20$214.35$214.35808,600$219.1337,802
2026-08-19$221.56$221.56886,800$215.0831,476
2026-08-18$212.55$212.55694,000$210.1032,109
2026-08-17$209.15$209.15617,100$208.7028,273
2026-08-14$209.83$209.83554,400$210.1938,356
2026-08-13$210.65$210.65860,100$212.4946,612
2026-08-12$208.87$208.87789,000$203.4533,352
2026-08-11$203.89$203.89936,800$206.4561,051
2026-08-10$207.13$207.13706,400$206.9753,959
2026-08-07$207.94$207.94840,500$207.9153,795
2026-08-06$206.28$206.28892,600$209.4838,249
2026-08-05$206.63$206.63873,700$210.3347,248
2026-08-04$208.45$208.451,205,400$200.1353,634
2026-08-03$201.82$201.82940,900$202.6335,264
2026-07-31$202.95$202.951,062,000$207.1452,641
2026-07-30$207.93$207.93892,900$204.5064,264
2026-07-29$209.23$209.232,400,100$209.87202,156
2026-07-28$205.61$205.611,831,900$200.94122,262
2026-07-27$200.14$200.14762,600$203.2656,032
2026-07-24$202.19$202.19596,300$202.6136,388
2026-07-23$200.62$200.621,032,100$199.0468,423
2026-07-22$197.74$197.74841,300$203.2671,349
2026-07-21$203.16$203.16652,800$199.5023,527
2026-07-20$199.95$199.95962,700$205.3740,120
2026-07-17$205.99$205.991,151,300
2026-07-16$208.92$208.921,872,700
2026-07-15$197.24$197.242,067,300
2026-07-14$191.95$191.953,902,100
2026-07-13$209.03$209.032,259,800
2026-07-10$199.15$199.151,133,100
2026-07-09$198.91$198.911,657,300
2026-07-08$200.36$200.361,947,700
2026-07-07$205.70$205.701,156,900
2026-07-06$208.46$208.461,218,400
2026-07-02$216.12$216.121,155,100
2026-07-01$209.74$209.741,138,600
2026-06-30$216.06$216.061,091,300
2026-06-29$216.63$216.631,279,800
2026-06-26$216.03$216.032,374,400
2026-06-25$201.96$201.961,328,900
2026-06-24$199.59$199.591,348,800
2026-06-23$197.19$197.191,053,500
2026-06-22$199.71$199.711,675,000
2026-06-18$196.58$196.581,729,800
2026-06-17$198.67$198.671,009,000
2026-06-16$195.61$195.611,110,700
2026-06-15$198.64$198.64883,900
2026-06-12$200.05$200.05837,300
2026-06-11$199.96$199.96914,700
2026-06-10$194.24$194.241,071,200
2026-06-09$199.10$199.10934,200
2026-06-08$192.62$192.621,162,400
2026-06-05$195.34$195.34880,400
2026-06-04$196.45$196.45719,100
2026-06-03$195.96$195.96891,500
2026-06-02$188.83$188.831,097,800
2026-06-01$192.23$192.23841,500
2026-05-29$196.00$196.001,905,400
2026-05-28$196.39$196.39556,200
2026-05-27$196.97$196.97893,000
2026-05-26$193.08$193.08930,100
2026-05-22$193.76$193.76892,900
2026-05-21$189.47$189.471,475,200
2026-05-20$187.80$187.80919,700
2026-05-19$190.56$190.561,054,100
2026-05-18$191.91$191.911,051,300
2026-05-15$192.95$192.951,252,200
2026-05-14$191.37$191.372,812,900
2026-05-13$204.53$204.531,271,900
2026-05-12$199.36$199.361,145,400
2026-05-11$197.95$197.951,772,200
2026-05-08$193.45$193.45931,500
2026-05-07$191.38$191.38735,600
2026-05-06$190.68$190.68741,300
2026-05-05$189.13$189.13586,100
2026-05-04$187.21$187.21626,600
2026-05-01$187.06$187.06696,800
2026-04-30$189.28$189.281,550,500
2026-04-29$194.38$194.382,453,400
2026-04-28$183.38$183.381,235,600
2026-04-27$180.67$180.671,101,400
2026-04-24$184.38$184.38723,300
2026-04-23$187.88$187.88816,300
2026-04-22$190.07$190.071,327,900
2026-04-21$185.95$185.951,063,200
2026-04-20$183.34$183.341,484,400
2026-04-17$177.35$177.351,239,500
2026-04-16$176.02$176.02953,500
2026-04-15$180.54$180.541,168,700