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.

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Historical Stock Price — 2018

DateSplit-adjusted closeCumulative dividend-reinvested closeReported volumeOpen priceExchange Volume
2018-12-31$300.92$300.921,064,300
2018-12-28$293.52$293.521,053,300
2018-12-27$294.41$294.411,477,600
2018-12-26$295.17$295.171,513,000
2018-12-24$278.50$278.50997,500
2018-12-21$280.60$280.603,070,800
2018-12-20$292.33$292.331,648,100
2018-12-19$292.69$292.692,036,600
2018-12-18$294.75$294.752,990,800
2018-12-17$313.10$313.101,397,600
2018-12-14$314.55$314.551,233,800
2018-12-13$320.14$320.141,220,700
2018-12-12$322.61$322.611,401,500
2018-12-11$319.79$319.791,050,100
2018-12-10$319.44$319.44968,100
2018-12-07$316.73$316.731,172,100
2018-12-06$326.70$326.701,575,600
2018-12-04$322.73$322.731,345,500
2018-12-03$332.19$332.191,131,500
2018-11-30$333.72$333.721,666,900
2018-11-29$326.61$326.61821,300
2018-11-28$332.24$332.241,067,700
2018-11-27$323.81$323.81964,400
2018-11-26$319.50$319.501,141,600
2018-11-23$320.08$320.08597,800
2018-11-21$315.56$315.56746,900
2018-11-20$319.48$319.481,357,000
2018-11-19$319.21$319.211,204,000
2018-11-16$324.05$324.051,542,100
2018-11-15$321.72$321.721,196,000
2018-11-14$313.55$313.551,390,900
2018-11-13$319.08$319.08839,400
2018-11-12$318.90$318.90954,900
2018-11-09$325.20$325.20783,000
2018-11-08$326.04$326.041,088,300
2018-11-07$331.51$331.511,371,500
2018-11-06$320.28$320.281,064,600
2018-11-05$317.15$317.151,020,000
2018-11-02$312.70$312.701,197,900
2018-11-01$315.33$315.331,331,100
2018-10-31$304.27$304.271,328,600
2018-10-30$306.28$306.281,482,700
2018-10-29$300.96$300.961,567,600
2018-10-26$300.17$300.172,174,300
2018-10-25$298.47$298.473,001,700
2018-10-24$302.05$302.052,766,800
2018-10-23$316.15$316.152,414,500
2018-10-22$315.54$315.541,736,300
2018-10-19$320.41$320.411,885,000
2018-10-18$330.15$330.151,002,500
2018-10-17$338.23$338.23939,800
2018-10-16$338.61$338.611,151,000
2018-10-15$328.41$328.41921,000
2018-10-12$330.94$330.941,264,900
2018-10-11$327.27$327.271,395,700
2018-10-10$337.53$337.531,420,200
2018-10-09$344.57$344.57778,900
2018-10-08$343.03$343.03852,400
2018-10-05$342.08$342.08989,100
2018-10-04$343.10$343.101,079,200
2018-10-03$352.75$352.751,119,400
2018-10-02$345.41$345.411,340,100
2018-10-01$352.56$352.56974,900
2018-09-28$353.31$353.311,542,900
2018-09-27$355.60$355.601,219,500
2018-09-26$349.37$349.371,595,600
2018-09-25$341.65$341.651,232,300
2018-09-24$347.02$347.021,016,300
2018-09-21$345.41$345.413,874,500
2018-09-20$341.24$341.241,085,000
2018-09-19$338.91$338.91844,800
2018-09-18$336.89$336.891,243,300
2018-09-17$334.40$334.40944,100
2018-09-14$338.68$338.68882,000
2018-09-13$340.58$340.58862,300
2018-09-12$340.03$340.03869,400
2018-09-11$337.70$337.70906,700
2018-09-10$340.25$340.251,105,500
2018-09-07$339.65$339.65997,600
2018-09-06$341.34$341.34833,800
2018-09-05$346.60$346.601,039,000
2018-09-04$346.72$346.721,296,800
2018-08-31$353.49$353.49867,200
2018-08-30$352.74$352.74875,900
2018-08-29$349.99$349.991,291,300
2018-08-28$345.53$345.531,125,900
2018-08-27$342.70$342.70704,600
2018-08-24$342.33$342.33620,000
2018-08-23$341.89$341.89750,000
2018-08-22$344.98$344.98597,500
2018-08-21$343.28$343.28625,200
2018-08-20$344.11$344.11821,700
2018-08-17$345.22$345.22917,300
2018-08-16$342.93$342.93882,500
2018-08-15$340.72$340.72953,200
2018-08-14$343.63$343.63883,400
2018-08-13$340.79$340.791,077,700
2018-08-10$343.00$343.001,359,100
2018-08-09$346.90$346.901,322,300
2018-08-08$350.09$350.09969,200
2018-08-07$350.10$350.101,614,900
2018-08-06$341.17$341.171,034,200
2018-08-03$344.21$344.211,164,400
2018-08-02$347.93$347.931,414,600
2018-08-01$344.06$344.061,688,400
2018-07-31$334.37$334.372,052,700
2018-07-30$331.46$331.462,408,400
2018-07-27$340.40$340.402,426,100
2018-07-26$344.74$344.744,924,000
2018-07-25$383.83$383.834,686,600
2018-07-24$372.84$372.844,191,700
2018-07-23$358.13$358.131,884,600
2018-07-20$358.71$358.711,666,300
2018-07-19$358.11$358.111,650,600
2018-07-18$358.51$358.511,399,800
2018-07-17$354.98$354.981,486,100
2018-07-16$353.03$353.031,460,100
2018-07-13$348.48$348.481,168,600
2018-07-12$347.66$347.661,304,400
2018-07-11$344.10$344.101,786,600
2018-07-10$344.82$344.823,425,600
2018-07-09$354.00$354.003,872,800
2018-07-06$357.48$357.4812,857,000
2018-07-05$298.81$298.81746,300
2018-07-03$293.51$293.51452,900
2018-07-02$295.77$295.771,116,400
2018-06-29$290.24$290.241,394,300
2018-06-28$288.75$288.751,405,900
2018-06-27$287.93$287.931,116,200
2018-06-26$291.92$291.92943,300
2018-06-25$292.19$292.191,685,500
2018-06-22$296.04$296.041,334,600
2018-06-21$297.34$297.341,206,700
2018-06-20$296.86$296.861,273,600
2018-06-19$292.04$292.041,706,200
2018-06-18$289.12$289.123,409,000
2018-06-15$305.03$305.031,882,400
2018-06-14$305.68$305.681,344,600
2018-06-13$306.91$306.911,180,300
2018-06-12$306.19$306.191,085,200
2018-06-11$306.68$306.681,178,900
2018-06-08$303.29$303.291,519,800
2018-06-07$305.37$305.371,392,900
2018-06-06$303.75$303.751,371,200
2018-06-05$298.64$298.641,206,300
2018-06-04$298.91$298.911,028,000
2018-06-01$297.09$297.091,238,800
2018-05-31$293.96$293.962,081,900
2018-05-30$294.40$294.401,987,500
2018-05-29$287.09$287.091,562,500
2018-05-25$286.21$286.211,464,200
2018-05-24$284.41$284.411,148,200
2018-05-23$283.75$283.751,398,200
2018-05-22$279.69$279.691,320,200
2018-05-21$277.67$277.671,628,100
2018-05-18$280.40$280.401,639,700
2018-05-17$280.57$280.571,830,700
2018-05-16$281.51$281.511,515,700
2018-05-15$276.06$276.061,729,000
2018-05-14$282.34$282.342,027,100
2018-05-11$282.39$282.391,908,700
2018-05-10$274.00$274.001,416,600
2018-05-09$274.03$274.031,377,300
2018-05-08$269.73$269.731,303,300
2018-05-07$269.70$269.701,296,800
2018-05-04$270.34$270.341,937,800
2018-05-03$266.44$266.441,999,000
2018-05-02$274.13$274.133,616,700
2018-05-01$274.61$274.611,910,300
2018-04-30$273.60$273.602,083,300
2018-04-27$276.80$276.801,955,600
2018-04-26$273.86$273.862,084,800
2018-04-25$269.45$269.452,765,700
2018-04-24$262.15$262.153,619,800
2018-04-23$259.30$259.301,922,300
2018-04-20$263.02$263.021,584,500
2018-04-19$266.02$266.02910,900
2018-04-18$268.03$268.031,382,200
2018-04-17$264.75$264.751,863,000
2018-04-16$263.11$263.111,323,300
2018-04-13$265.39$265.391,197,100
2018-04-12$267.44$267.441,238,300
2018-04-11$265.99$265.991,771,500
2018-04-10$265.09$265.091,983,200
2018-04-09$257.52$257.522,235,500
2018-04-06$257.65$257.651,954,000
2018-04-05$264.98$264.981,804,300
2018-04-04$272.40$272.401,603,100
2018-04-03$266.48$266.481,456,600
2018-04-02$266.89$266.891,550,300
2018-03-29$273.82$273.821,237,800
2018-03-28$271.82$271.821,991,800
2018-03-27$265.16$265.161,880,500
2018-03-26$268.20$268.202,226,800
2018-03-23$260.13$260.133,039,600
2018-03-22$271.89$271.891,748,600
2018-03-21$277.29$277.291,340,000
2018-03-20$279.68$279.681,313,400
2018-03-19$278.37$278.371,530,400
2018-03-16$287.62$287.622,294,200
2018-03-15$286.70$286.701,342,900
2018-03-14$285.72$285.722,039,500
2018-03-13$283.24$283.242,258,600
2018-03-12$279.90$279.902,349,000
2018-03-09$286.10$286.101,715,000
2018-03-08$284.69$284.691,313,700
2018-03-07$284.54$284.541,404,900
2018-03-06$285.98$285.98881,700
2018-03-05$286.95$286.95904,300
2018-03-02$286.96$286.961,511,900
2018-03-01$282.35$282.352,339,200
2018-02-28$288.99$288.991,742,400
2018-02-27$290.10$290.101,697,400
2018-02-26$290.01$290.011,448,300
2018-02-23$292.78$292.782,541,500
2018-02-22$284.81$284.812,484,700
2018-02-21$286.10$286.101,922,400
2018-02-20$287.45$287.452,004,500
2018-02-16$291.87$291.872,943,100
2018-02-15$299.38$299.383,040,900
2018-02-14$296.08$296.085,426,400
2018-02-13$316.99$316.99732,900
2018-02-12$316.63$316.631,331,000
2018-02-09$316.78$316.782,180,400
2018-02-08$311.79$311.791,414,600
2018-02-07$326.89$326.891,237,300
2018-02-06$332.86$332.861,768,200
2018-02-05$328.31$328.311,541,300
2018-02-02$343.83$343.831,095,000
2018-02-01$346.00$346.001,372,900
2018-01-31$347.81$347.811,398,000
2018-01-30$352.59$352.591,127,800
2018-01-29$358.48$358.481,317,200
2018-01-26$367.91$367.912,232,700
2018-01-25$353.74$353.741,863,000
2018-01-24$346.50$346.501,512,600
2018-01-23$346.75$346.751,186,200
2018-01-22$347.64$347.641,195,200
2018-01-19$342.41$342.411,232,200
2018-01-18$344.44$344.441,302,500
2018-01-17$344.87$344.871,429,000
2018-01-16$338.85$338.851,256,800
2018-01-12$335.95$335.95885,500
2018-01-11$333.07$333.071,002,000
2018-01-10$336.72$336.72973,400
2018-01-09$336.36$336.361,326,400
2018-01-08$329.65$329.651,438,800
2018-01-05$342.49$342.491,486,400
2018-01-04$339.99$339.99967,100
2018-01-03$339.85$339.851,121,700
2018-01-02$334.17$334.171,422,500