Massivemarkets

BIIB

Biogen Inc. Common Stock

Nasdaq · usd

$252.28-1.56 (-0.61%)
As of 9:13:20 AM EDT on Oct 23, 2026 · 15-minute delayed

Biogen Inc. Common Stock (BIIB) trades at $252.28 (-0.61%) as of 9:13:20 AM EDT on Oct 23, 2026, +11.56% over the past month. Market cap is $37.51B, with 4.9 days to cover in short interest.

Stock performance

How Biogen Inc. Common Stock (BIIB) stock has performed from one day to one year, with its 52-week range.

+4.20%
+$10.23 over 1D
$240.94$245.06$249.17$253.288:15 AM11:05 AM12:50 PM2:30 PM8:00 PM$253.74
1D
+5.34%
1W
+7.86%
1M
+11.56%
YTD
+44.24%
1Y
+69.35%
52-wk range
$138.00 – $254.41

Key statistics

Today's trading snapshot for BIIB: day range, open, previous close, volume and market cap.

Day range
$240.02 – $254.41
Open
$240.61
Prev close
$253.84
Volume
2.24M
Market cap
$37.51B
Shares out
147.75M

Valuation and profitability ratios: P/E, P/S, ROE

Valuation and profitability ratios for Biogen Inc. Common Stock: P/E, P/S, P/B, ROE and more.

P/E
44.94
P/S
3.74
P/B
1.99
P/FCF
13.91
ROE
4.4%
ROA
2.6%
Debt/Equity
0.43
Div yield
0.00%

As of Oct 22, 2026

8-K filings

Material corporate events Biogen Inc. Common Stock has disclosed to the SEC on Form 8-K.

  • Shareholder meetingsJun 10, 2026

    On June 9, 2026, Biogen Inc. (the "Company") held its 2026 Annual Meeting of Stockholders. The final voting results for this meeting are as follows: Stockholders elected ten nominees to the Board of Directors to serve for a one-year term extending until the 2027 annual meeting of stockholders.

  • Debt activityMay 14, 2026

    On May 13, 2026, in connection with the completion of the Offer and the Merger, Biogen borrowed the full amount available under the Credit Agreement. The proceeds from the borrowings under the Term Facilities were used to pay a portion of the consideration for the Offer and the Merger and for other purposes in connection with the Transactions.

  • Earnings and performanceApr 6, 2026

    Results for the quarter ended March 31, 2026, have not been finalized and are subject to our financial statement closing procedures. There can be no assurance that our final results will not differ from the preliminary unaudited estimates described herein.

  • Investor communicationsMar 31, 2026

    On March 31, 2026, Biogen held an investor webcast presentation announcing the Merger. A copy of the investor webcast presentation relating to the Merger is attached as Exhibit 99.3 to this Current Report on Form 8-K and is incorporated herein by reference.

  • Executive leadershipMar 11, 2026

    Susan H. Alexander, Chief Legal Officer, will depart from the Company effective as of the end May, 2026. The Company has initiated a search to identify the Company's next Chief Legal Officer.

BIIB short interest

How heavily BIIB is shorted: shares short, days to cover and average daily volume.

Days to cover
4.9
Short interest
5.97M
Avg volume
1.23M

As of · reported to FINRA twice monthly.

BIIB news

The latest news and headlines about Biogen Inc. Common Stock (BIIB).

Frequently asked questions

What is the Biogen Inc. Common Stock (BIIB) stock price today?

Biogen Inc. Common Stock (BIIB) is trading at $252.28 (-0.61% on the day) as of 9:13:20 AM EDT on Oct 23, 2026. Prices are delayed at least 15 minutes; real-time quotes are available from the Massive API.

What is Biogen Inc. Common Stock?

Biogen is an established biopharmaceutical company focused on treatments for neurodegenerative and rare diseases. Its declining multiple sclerosis franchise is its largest revenue generator and contributed 40% of total revenue in 2025.

What is the short interest in BIIB?

As of Sep 30, 2026, BIIB has 5.97M shares short and 4.9 days to cover.

What exchange is BIIB listed on?

Biogen Inc. Common Stock (BIIB) trades on Nasdaq in USD, in the BIOLOGICAL PRODUCTS, (NO DIAGNOSTIC SUBSTANCES) industry.

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