NASDAQ:BIIB | Historical Stock Price | 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.

View year

Historical Stock Price — 2000

DateSplit-adjusted closeCumulative dividend-reinvested closeReported volumeOpen priceExchange Volume
2000-12-29$63.19$63.195,163,000
2000-12-28$65.58$65.584,030,500
2000-12-27$66.65$66.652,869,800
2000-12-26$67.46$67.464,161,300
2000-12-22$65.31$65.313,704,700
2000-12-21$62.40$62.406,119,700
2000-12-20$61.35$61.358,911,200
2000-12-19$66.79$66.7911,128,800
2000-12-18$75.08$75.086,544,800
2000-12-15$69.81$69.8114,466,600
2000-12-14$69.40$69.403,975,000
2000-12-13$67.79$67.794,326,300
2000-12-12$69.17$69.176,350,100
2000-12-11$72.67$72.675,640,000
2000-12-08$71.10$71.106,378,600
2000-12-07$67.69$67.692,970,000
2000-12-06$66.17$66.175,383,800
2000-12-05$62.96$62.964,697,400
2000-12-04$57.79$57.796,322,200
2000-12-01$59.67$59.675,493,900
2000-11-30$58.02$58.025,879,400
2000-11-29$61.92$61.924,498,800
2000-11-28$62.88$62.884,701,600
2000-11-27$64.85$64.857,424,100
2000-11-24$56.50$56.502,169,300
2000-11-22$56.06$56.064,686,900
2000-11-21$53.81$53.816,277,500
2000-11-20$50.81$50.818,979,900
2000-11-17$56.83$56.837,331,400
2000-11-16$58.48$58.488,548,200
2000-11-15$60.60$60.605,768,700
2000-11-14$56.96$56.967,041,300
2000-11-13$56.50$56.509,887,700
2000-11-10$66.56$66.562,011,200
2000-11-09$69.81$69.815,649,900
2000-11-08$73.42$73.423,610,500
2000-11-07$70.04$70.042,451,600
2000-11-06$69.69$69.693,878,100
2000-11-03$71.25$71.253,266,400
2000-11-02$72.69$72.695,688,000
2000-11-01$68.71$68.714,222,200
2000-10-31$65.38$65.383,495,000
2000-10-30$61.58$61.582,773,500
2000-10-27$61.63$61.632,532,000
2000-10-26$63.40$63.403,934,500
2000-10-25$62.33$62.335,685,600
2000-10-24$66.92$66.925,764,800
2000-10-23$65.63$65.635,017,200
2000-10-20$63.42$63.423,651,000
2000-10-19$62.88$62.885,436,600
2000-10-18$62.63$62.636,116,100
2000-10-17$60.69$60.697,329,900
2000-10-16$55.88$55.882,850,600
2000-10-13$54.17$54.173,147,900
2000-10-12$53.29$53.294,526,400
2000-10-11$54.76$54.764,712,400
2000-10-10$56.33$56.334,115,400
2000-10-09$54.92$54.922,649,900
2000-10-06$53.71$53.711,654,800
2000-10-05$53.75$53.752,041,200
2000-10-04$53.69$53.691,709,400
2000-10-03$53.02$53.024,274,100
2000-10-02$52.33$52.334,101,900
2000-09-29$58.45$58.451,738,800
2000-09-28$58.52$58.522,863,800
2000-09-27$57.31$57.312,949,300
2000-09-26$56.75$56.753,518,100
2000-09-25$56.08$56.083,619,200
2000-09-22$56.81$56.813,575,100
2000-09-21$55.75$55.753,796,800
2000-09-20$51.06$51.063,108,900
2000-09-19$48.90$48.902,614,200
2000-09-18$46.44$46.441,659,000
2000-09-15$48.79$48.792,378,700
2000-09-14$47.25$47.251,838,100
2000-09-13$45.92$45.921,527,300
2000-09-12$45.33$45.331,716,900
2000-09-11$45.83$45.833,266,700
2000-09-08$48.98$48.982,824,500
2000-09-07$47.00$47.001,712,100
2000-09-06$44.58$44.582,542,800
2000-09-05$46.52$46.522,111,400
2000-09-01$50.31$50.313,680,100
2000-08-31$46.54$46.541,907,400
2000-08-30$45.31$45.311,517,400
2000-08-29$45.96$45.961,726,800
2000-08-28$46.58$46.582,308,800
2000-08-25$46.46$46.462,696,100
2000-08-24$45.46$45.462,037,600
2000-08-23$42.52$42.521,795,500
2000-08-22$42.46$42.461,790,400
2000-08-21$43.42$43.42841,500
2000-08-18$43.98$43.981,485,600
2000-08-17$43.85$43.852,052,600
2000-08-16$41.92$41.922,292,300
2000-08-15$43.06$43.061,161,900
2000-08-14$44.27$44.271,806,600
2000-08-11$45.33$45.332,750,700
2000-08-10$46.79$46.791,851,000
2000-08-09$45.00$45.00935,100
2000-08-08$45.38$45.381,636,800
2000-08-07$47.58$47.582,368,200
2000-08-04$45.67$45.671,377,300
2000-08-03$45.29$45.292,631,300
2000-08-02$44.81$44.815,143,500
2000-08-01$42.92$42.923,551,100
2000-07-31$40.94$40.942,719,500
2000-07-28$38.67$38.674,848,600
2000-07-27$42.52$42.523,320,400
2000-07-26$41.85$41.853,715,500
2000-07-25$38.48$38.482,028,300
2000-07-24$39.38$39.382,169,900
2000-07-21$39.77$39.771,581,000
2000-07-20$40.04$40.042,096,700
2000-07-19$39.83$39.832,792,400
2000-07-18$41.42$41.422,338,500
2000-07-17$42.27$42.275,261,400
2000-07-14$39.33$39.332,640,600
2000-07-13$38.13$38.134,128,900
2000-07-12$41.67$41.672,088,600
2000-07-11$43.69$43.694,359,000
2000-07-10$43.17$43.172,201,700
2000-07-07$43.38$43.382,049,900
2000-07-06$44.38$44.384,831,500
2000-07-05$43.42$43.425,149,800
2000-07-03$39.67$39.67674,400
2000-06-30$39.10$39.109,203,700
2000-06-29$41.35$41.353,800,700
2000-06-28$42.21$42.213,868,200
2000-06-27$38.44$38.443,249,900
2000-06-26$39.31$39.315,159,100
2000-06-23$37.83$37.833,357,300
2000-06-22$36.17$36.174,328,700
2000-06-21$40.88$40.884,610,400
2000-06-20$38.98$38.985,620,800
2000-06-19$40.08$40.087,587,000
2000-06-16$34.85$34.854,965,600
2000-06-15$32.63$32.6313,121,700
2000-06-14$32.52$32.523,642,900
2000-06-13$34.48$34.483,666,300
2000-06-12$31.65$31.651,502,100
2000-06-09$33.42$33.422,730,600
2000-06-08$31.13$31.13969,600
2000-06-07$31.71$31.712,778,000
2000-06-06$32.06$32.065,550,300
2000-06-05$29.58$29.583,616,500
2000-06-02$28.81$28.814,477,500
2000-06-01$25.04$25.044,093,800
2000-05-31$21.27$21.272,706,900
2000-05-30$21.79$21.792,584,200
2000-05-26$21.04$21.041,104,300
2000-05-25$20.00$20.002,850,600
2000-05-24$21.31$21.312,506,500
2000-05-23$21.04$21.044,089,600
2000-05-22$20.65$20.653,324,300
2000-05-19$23.29$23.292,467,200
2000-05-18$23.92$23.922,700,300
2000-05-17$23.88$23.882,463,000
2000-05-16$24.98$24.982,035,200
2000-05-15$25.04$25.041,659,300
2000-05-12$26.17$26.172,158,800
2000-05-11$24.54$24.541,290,300
2000-05-10$24.10$24.101,229,400
2000-05-09$24.35$24.352,266,800
2000-05-08$24.90$24.902,059,500
2000-05-05$25.06$25.062,933,100
2000-05-04$23.88$23.882,370,300
2000-05-03$21.65$21.652,141,700
2000-05-02$22.31$22.313,667,800
2000-05-01$24.04$24.046,054,600
2000-04-28$21.33$21.335,520,000
2000-04-27$19.33$19.333,364,800
2000-04-26$20.06$20.062,946,600
2000-04-25$19.92$19.925,605,800
2000-04-24$19.13$19.134,710,600
2000-04-20$21.04$21.0415,258,300
2000-04-19$25.79$25.794,341,600
2000-04-18$24.08$24.084,002,000
2000-04-17$21.56$21.565,349,000
2000-04-14$24.00$24.004,941,000
2000-04-13$25.83$25.832,982,300
2000-04-12$26.81$26.8115,035,700
2000-04-11$29.48$29.483,858,600
2000-04-10$32.29$32.291,719,300
2000-04-07$33.77$33.773,473,700
2000-04-06$35.69$35.693,437,400
2000-04-05$36.67$36.675,295,300
2000-04-04$32.17$32.174,142,400
2000-04-03$31.38$31.383,118,500
2000-03-31$32.75$32.754,108,200
2000-03-30$28.92$28.926,728,400
2000-03-29$32.21$32.218,186,400
2000-03-28$37.83$37.832,055,000
2000-03-27$39.15$39.152,810,700
2000-03-24$39.67$39.672,843,700
2000-03-23$42.04$42.043,172,500
2000-03-22$43.75$43.754,879,500
2000-03-21$38.53$38.5310,193,700
2000-03-20$35.50$35.503,603,000
2000-03-17$39.65$39.653,074,700
2000-03-16$39.96$39.968,469,900
2000-03-15$36.19$36.199,727,500
2000-03-14$35.00$35.0010,685,400
2000-03-13$38.58$38.584,317,600
2000-03-10$43.10$43.103,360,000
2000-03-09$47.63$47.631,603,800
2000-03-08$50.88$50.881,746,300
2000-03-07$52.85$52.853,462,300
2000-03-06$57.10$57.104,146,000
2000-03-03$50.00$50.002,667,000
2000-03-02$46.35$46.351,827,000
2000-03-01$48.94$48.941,934,700
2000-02-29$46.96$46.962,574,600
2000-02-28$44.50$44.504,113,900
2000-02-25$45.81$45.811,927,800
2000-02-24$46.25$46.252,410,800
2000-02-23$46.31$46.311,815,300
2000-02-22$41.63$41.632,592,900
2000-02-18$43.96$43.965,254,500
2000-02-17$43.88$43.885,101,800
2000-02-16$40.63$40.634,291,200
2000-02-15$38.79$38.791,440,600
2000-02-14$39.60$39.601,397,400
2000-02-11$39.60$39.602,169,600
2000-02-10$39.06$39.062,262,600
2000-02-09$41.00$41.003,266,100
2000-02-08$43.29$43.295,076,900
2000-02-07$38.27$38.273,684,000
2000-02-04$36.50$36.503,219,900
2000-02-03$34.38$34.388,475,600
2000-02-02$35.33$35.3316,296,900
2000-02-01$44.31$44.311,500,900
2000-01-31$42.06$42.062,177,400
2000-01-28$42.75$42.751,899,600
2000-01-27$43.42$43.421,650,600
2000-01-26$47.79$47.793,650,700
2000-01-25$45.29$45.294,178,100
2000-01-24$45.77$45.774,815,300
2000-01-21$49.25$49.259,227,100
2000-01-20$40.90$40.9015,550,500
2000-01-19$40.33$40.332,685,000
2000-01-18$35.69$35.693,359,400
2000-01-14$38.50$38.502,877,900
2000-01-13$38.71$38.713,178,500
2000-01-12$35.21$35.214,256,100
2000-01-11$36.71$36.713,385,200
2000-01-10$39.83$39.835,765,400
2000-01-07$36.10$36.104,736,400
2000-01-06$32.38$32.382,742,300
2000-01-05$31.00$31.003,390,000
2000-01-04$28.98$28.982,935,500
2000-01-03$31.08$31.082,792,700