2018 Annual Meeting of

Stockholders and Proxy Statement

        Tuesday, June 12, 2018

        9:00 a.m. Eastern Time

        To be held at our offices located at 225 Binney Street,

        Cambridge, Massachusetts 02142 and

        online at www.virtualshareholdermeeting.com/BIIB2018

April 27, 2018

To My Fellow Stockholders:

On behalf of the Board of Directors, I want to thank you for your investment in Biogen and for the confidence you put in this Board to oversee your interests in this business.

Biogen’s mission is clear: We are pioneers in neuroscience. We believe that no other disease area holds as much need or as much promise for medical breakthroughs with approximately one billion people affected by neurological disorders worldwide.

Our philosophy of Caring Deeply. Working Fearlessly. Changing Lives.^™ informs our policies and business practices. We work to have an impact beyond our medicines as we strive to improve patient health outcomes, solve social and environmental challenges, cultivate a workplace that enables our employees to thrive, support local communities and inspire future generations of scientists.

The Board takes its role in overseeing Biogen’s long-term business strategy very seriously. In 2017 the Board stewarded a successful leadership succession plan with the transition to our new CEO, Michel Vounatsos, who has begun implementing our newly focused strategy as we continue to work toward our goal of broadening our leadership role in neuroscience.

We are proud of our accomplishments in 2017, including:

On behalf of the Board, I am pleased to invite you to attend our 2018 annual meeting of stockholders, which will be held at our offices located at 225 Binney Street, Cambridge, Massachusetts 02142 on Tuesday, June 12, 2018, beginning at 9:00 a.m. Eastern Time. For those who cannot attend in person, we are offering a virtual stockholder

meeting in which you can view the meeting, submit questions and vote online at www.virtualshareholdermeeting.com/BIIB2018. You will need the 16-digit control number included with these proxy materials to attend the annual meeting virtually via the Internet. Stockholders who attend the annual meeting virtually via the Internet will have the opportunity to participate fully in the meeting on an equal basis with those who attend in person.

The following notice of our annual meeting of stockholders contains details of the business to be conducted at the meeting. Only stockholders of record at the close of business on April 17, 2018, will be entitled to notice of, and to vote at, the annual meeting.

On behalf of the Board of Directors, I thank you for your continued support and investment in Biogen.

Very truly yours,

STELIOS PAPADOPOULOS

Chairman of the Board

On behalf of the Board of Directors of Biogen Inc.

Binney Street Cambridge,

Massachusetts 02142

By Order of Our Board of Directors,

SUSAN H. ALEXANDER,

Secretary

225 Binney Street

Cambridge, Massachusetts 02142

April 27, 2018

This Notice and Proxy Statement are first being sent to stockholders on or about April 27, 2018. Our 2017 Annual Report on Form 10-K is being sent with this Notice and Proxy Statement.

This summary highlights important information you will find in this Proxy Statement. As it is only a summary, please review the complete Proxy Statement before you vote.

-iii-

Our mission is clear: We are pioneers in neuroscience. We believe that no other disease area holds as much need or as much promise for medical breakthroughs with approximately one billion people affected by neurological disorders worldwide.

We are focused on discovering, developing and delivering worldwide innovative therapies for people living with serious neurological and neurodegenerative diseases, including in our core growth areas of multiple sclerosis (MS) and neuroimmunology, Alzheimer’s disease and dementia, movement disorders and neuromuscular disorders, including spinal muscular atrophy (SMA) and amyotrophic lateral sclerosis. We also plan to invest in emerging growth areas such as pain, ophthalmology, neuropsychiatry and acute neurology. In addition, we are employing innovative technologies to discover potential treatments for rare and genetic disorders, including new ways of treating diseases through gene therapy in the previously mentioned areas. We also manufacture and commercialize biosimilars of advanced biologics. For additional information, please see our 2017 Annual Report on Form 10-K.

2017 Operating Performance Highlights

-iv-

We strive to maintain effective corporate governance practices to ensure that our company is managed for the long-term benefit of our stockholders. To that end, we continually review and refine our corporate governance policies, procedures and practices. See Part 2 – “Corporate Governance at Biogen” for more information.

Corporate Governance Highlights

Director - Stockholder Engagement Initiative

We value the views of our stockholders and other stakeholders, and we solicit input throughout the year on topics such as business strategy, capital allocation, corporate governance, executive compensation, sustainability and corporate social responsibility initiatives. During fiscal 2017, independent members of our Board of Directors conducted outreach to certain stockholders to discuss a variety of issues, including business, corporate governance and compensation related matters.

-v-

Proposal 1 — Election of Directors

You are being asked to vote on the election of the following 11 nominees for director. All directors are elected annually by the affirmative vote of a majority of votes cast. Detailed information about each director’s background, skill sets and areas of expertise can be found beginning on page 11.

						Committee Memberships*												Other Public Boards
Name, Occupation, and Experience		Age*		Independent		AC		CC		CGC		FC		RC		STC
Alexander J. Denner, Ph.D.   Founding Partner, Sarissa Capital		48		Yes														1
Caroline D. Dorsa   Retired Executive Vice President and Chief Financial Officer,   Public Service Enterprise Group Incorporated		58		Yes														3
Nancy L. Leaming   Retired Chief Executive Officer and President, Tufts Health Plan		70		Yes														—
Richard C. Mulligan, Ph.D.   Mallinckrodt Professor of Genetics, Emeritus, Harvard Medical School and   Portfolio Manager, Icahn Capital LP		63		Yes														—
Robert W. Pangia   Partner, Ivy Capital Partners, LLC		66		Yes														—
Stelios Papadopoulos, Ph.D.   Chairman, Biogen Inc., Chairman, Exelixis, Inc. and Chairman, Regulus   Therapeutics Inc.		69		Yes														3
Brian S. Posner   Private Investor and President, Point Rider Group LLC		56		Yes														2
Eric K. Rowinsky, M.D.   President and Executive Chairman of RGenix, Inc.		61		Yes														2
The Honorable Lynn Schenk, J.D.   Attorney, Former Chief of Staff to the Governor of California and   Former U.S. Congresswoman		73		Yes														1
Stephen A. Sherwin, M.D.   Clinical Professor of Medicine, University of California, San   Francisco and Advisor to Life Sciences Companies		69		Yes														2
Michel Vounatsos   Chief Executive Officer, Biogen Inc.		56		No														—

* Age and Committee memberships are as of April 17, 2018.

Chair:		Member:		Financial Expert:

-vi-

Proposal 2 – Ratification of Independent Registered Public Accounting Firm

You are being asked to vote to ratify the selection of PricewaterhouseCoopers LLP as our independent registered public accounting firm for the year ending December 31, 2018. Detailed information about this proposal can be found beginning on page 25.

Proposal 3 – Advisory Vote on Executive Compensation

Our Board of Directors recommends that stockholders vote to approve, on an advisory basis, the compensation paid to the Company’s named executive officers (NEOs) as described in this Proxy Statement (the “say-on-pay” vote). Detailed information about the compensation paid to our NEOs can be found beginning on page 28.

Our compensation programs embody a pay-for-performance philosophy that supports our business strategy and aligns executive interests with those of our stockholders. Highlights of our compensation programs for 2017 and our compensation best practices follow.

-vii-

Proposal 4 – Stockholder Proposal Requesting Certain Proxy Access Bylaw Amendments

Our Board of Directors recommends that stockholders vote against a stockholder proposal requesting certain amendments to our Fourth Amended and Restated Bylaws relating to proxy access to remove the limit on aggregating shares to meet the stockholding requirement and remove the limitation on renomination of persons based on votes in a prior year. Detailed information about this proposal can be found beginning on page 64.

Proposal 5 – Requesting a Report on the Extent to Which Risks Related to Public Concern Over Drug Pricing Strategies are Integrated into Incentive Compensation Arrangements

Our Board of Directors recommends that stockholders vote against a stockholder proposal requesting that the Compensation and Management Development Committee of our Board of Directors report annually on the extent to which risks related to public concern over drug pricing strategies are integrated into our incentive compensation policies, plans and programs. Detailed information about this proposal can be found beginning on page 66.

This Proxy Statement contains forward-looking statements, including statements relating to: our strategy and plans; potential of our commercial business and pipeline programs; capital allocation and investment strategy; clinical trials and data readouts and presentations and anticipated benefits and potential of investments, collaborations and business development activities. These forward-looking statements may be accompanied by such words as “aim,” “anticipate,” “believe,” “could,” “estimate,” “expect,” “forecast,” “intend,” “may,” “plan,” “potential,” “possible,” “will” and other words and terms of similar meaning. You should not place undue reliance on these statements.

These statements involve risks and uncertainties that could cause actual results to differ materially from those reflected in such statements, including the risks and uncertainties that are described in the Risk Factors section of our most recent annual or quarterly report and in other reports we have filed with the Securities and Exchange Commission (SEC). These statements are based on our current beliefs and expectations and speak only as of the date of this Proxy Statement. We do not undertake any obligation to publicly update any forward-looking statements, whether as a result of new information, future developments or otherwise.

SPINRAZA^®, TECFIDERA^®, TYSABRI^® and ZINBRYTA^® are registered trademarks of Biogen. ALPROLIX^®, ELOCTATE^®, HUMIRA^® and other trademarks referenced in this report are the property of their respective owners.

-viii-

Biogen Inc.

225 Binney Street

Cambridge, Massachusetts 02142

The Board of Directors of Biogen Inc. is soliciting your proxy to vote at our 2018 annual meeting of stockholders (Annual Meeting) to be held at 9:00 a.m. Eastern Time on Tuesday, June 12, 2018, for the purposes summarized in the accompanying Notice of 2018 Annual Meeting of Stockholders. Our 2017 Annual Report on Form 10-K is also available with this Proxy Statement.

References in this Proxy Statement to “Biogen” or the “Company,” “we,” “us” and “our” refer to Biogen Inc.

1

Our Board of Directors currently consists of the following directors, all serving one-year terms extending until the Annual Meeting and until their successors are duly elected and qualified:

All directors are standing for reelection to serve a one-year term extending until the 2019 annual meeting of stockholders and until their successors are duly elected and qualified, unless they resign or are removed. Our Board of Directors has nominated these 11 directors based on its carefully considered judgment that the experience, qualifications, attributes and skills of our nominees qualify them to serve on our Board of Directors. As described in detail below, our nominees have considerable professional and business expertise. We know of no reason why any nominee would be unable to accept nomination or election.

If any nominee is unable to serve on our Board of Directors, the shares represented by your proxy will be voted for the election of such other person as may be nominated by our Board of Directors. In addition, in compliance with all applicable state and federal laws and regulations, we will file an amended proxy statement and proxy card that, as applicable, (1) identifies the alternate nominee(s), (2) discloses that such nominees have consented to being named in the revised proxy statement and to serve if elected and (3) includes the disclosure required by Item 7 of Schedule 14A with respect to such nominees. All nominees have consented to be named in this Proxy Statement and to serve if elected.

Our Nominees for Director

_{(Information is as of April 17, 2018)}

Dr. Denner, 48, has served as one of our directors since 2009. Dr. Denner is a founding partner and Chief Investment Officer of Sarissa Capital Management LP, a registered investment advisor, which he founded in 2012. Sarissa Capital focuses on improving the strategies of companies to enhance stockholder value. From 2006 to 2011, Dr. Denner served as a Senior Managing Director at Icahn Capital. Prior to that, he served as a portfolio manager at Viking Global Investors, a private investment fund, and Morgan Stanley Investment Management, a global asset management firm. Dr. Denner is also a director of The Medicines Company, a biopharmaceutical company.

Dr. Denner has significant experience overseeing the operations and research and development of healthcare companies and evaluating corporate governance matters. He also has extensive experience as an investor, particularly with respect to healthcare companies, and possesses broad healthcare industry knowledge.

– Corporate Governance (Chair)

– Finance

– The Medicines Company

– Ariad Pharmaceuticals, Inc. (Chair)

– Bioverativ Inc.

– Enzon Pharmaceuticals, Inc.

– Vivus, Inc.

11

Ms. Dorsa, 58, has served as one of our directors since 2010. Ms. Dorsa served as the Executive Vice President and Chief Financial Officer of Public Service Enterprise Group Incorporated, a diversified energy company, from April 2009 until her retirement in October 2015, and served on its Board of Directors from February 2003 to April 2009. From February 2008 to April 2009, she served as Senior Vice President, Global Human Health, Strategy and Integration at Merck & Co., Inc., a pharmaceutical company. From November 2007 to January 2008, Ms. Dorsa served as Senior Vice President and Chief Financial Officer of Gilead Sciences, Inc., a life sciences company. From February 2007 to November 2007, she served as Senior Vice President and Chief Financial Officer of Avaya, Inc., a telecommunications company. From 1987 to January 2007, Ms. Dorsa held various financial and operational positions at Merck & Co., Inc., including Vice President and Treasurer, Executive Director of U.S. Customer Marketing and Executive Director of U.S. Pricing and Strategic Planning. Ms. Dorsa also serves as a director of Illumina, Inc. and Intellia Therapeutics, Inc., both of which are biotechnology companies, and as a Trustee of the Goldman Sachs ETF Trust, the Goldman Sachs MLP and Energy Renaissance Fund and the Goldman Sachs MLP Income Opportunities Fund, investment funds within the Goldman Sachs Asset Management fund complex.

Ms. Dorsa has significant financial and accounting expertise and a deep knowledge of the pharmaceutical industry. Her strategic perspective on the industry is particularly valuable to our Board of Directors as it oversees our growth initiatives and reviews both internal development projects and external opportunities.

– Audit (Chair)

– Risk

– Illumina, Inc.

– Intellia Therapeutics, Inc.

– Goldman Sachs Investment Funds

– None

Ms. Leaming, 70, has served as one of our directors since 2008. Ms. Leaming has been an independent consultant since 2005. From 2003 to 2005, she served as the Chief Executive Officer and President of Tufts Health Plan, a provider of healthcare insurance. From 1986 to 2003, Ms. Leaming served in several executive positions at Tufts Health Plan, including President, Chief Operating Officer and Chief Financial Officer.

Ms. Leaming has well-developed leadership skills and financial acumen and provides insights into the healthcare reimbursement and payer market, where she served for 20 years in senior operational, financial and managerial roles.

– Audit

– Risk

– None

– Edgewater Technology, Inc.

– Hologic, Inc.

12

Dr. Mulligan, 63, has served as one of our directors since 2009. Dr. Mulligan is currently the Mallinckrodt Professor of Genetics, Emeritus, at Harvard Medical School, after serving as the Mallinckrodt Professor of Genetics and Director of the Harvard Gene Therapy Initiative from 1996 to 2013. He also currently serves as a Portfolio Manager at Icahn Capital LP, a position held since March 2017. Prior to Harvard, Dr. Mulligan was a Professor of Molecular Biology at the Massachusetts Institute of Technology, a member of the Whitehead Institute for Biomedical Research and the Chief Scientific Officer of Somatix Therapy Corporation, a drug discovery and development company that he founded. Dr. Mulligan was a founding partner of Sarissa Capital Management LP, a registered investment advisor, from 2013 to 2016. Dr. Mulligan was named a MacArthur Foundation Fellow in 1981.

Dr. Mulligan has scientific expertise in the areas of molecular biology, genetics, gene therapy and biotechnology, as well as extensive experience within the healthcare industry, including overseeing the operations and research and development of healthcare companies.

– Science and Technology (Chair)

– Compensation and Management Development

– None

– Enzon Pharmaceuticals, Inc.

Mr. Pangia, 66, served as a director of the Company from 1997 to 2003 during the period the Company was operated as IDEC Pharmaceuticals, and has served as a director since 2003 following IDEC’s merger with Biogen, Inc. Mr. Pangia has been a partner in Ivy Capital Partners, LLC, the general partner of Ivy Healthcare Capital, L.P., a private equity fund specializing in healthcare investments, since 2003. From 2011 to 2016 he was also the Chief Executive Officer of Ivy Sports Medicine, LLC, a medical device company. From October 2007 to October 2009, he also served as the Chief Executive Officer of Highlands Acquisition Corp., a special purpose acquisition company. From 1996 to 2003, Mr. Pangia was self-employed as an investment banker. From 1987 to 1996, he held various senior management positions at PaineWebber, a financial services company, including Executive Vice President and Director of Investment Banking for PaineWebber Incorporated of New York, a member of the Board of Directors of PaineWebber, Inc., Chairman of PaineWebber Properties, Inc. and a member of several of PaineWebber’s executive and operating committees.

Mr. Pangia has significant financial acumen and breadth of expertise within the healthcare industry.

– Compensation and Management Development (Chair)

– Finance

– None

– None

13

Dr. Papadopoulos, 69, has served as one of our directors since 2008 and as our independent Chairman since June 2014. Dr. Papadopoulos also serves as the Chairman of Exelixis, Inc., a drug discovery and development company that he co-founded in 1994, and Regulus Therapeutics Inc., a biopharmaceutical company. Previously, he was an investment banker with Cowen & Co., LLC, a financial services company, focusing on the biotechnology and pharmaceutical sectors, from 2000 until his retirement as Vice Chairman in August 2006. Prior to joining Cowen & Co., Dr. Papadopoulos served for 13 years as an investment banker at PaineWebber, Inc., a financial services company, where he was most recently Chairman of PaineWebber Development Corp., a PaineWebber subsidiary focusing on biotechnology. Dr. Papadopoulos is also a director of BG Medicine, Inc., a diagnostics company focused on the development and commercialization of cardiovascular diagnostic tests.

Having founded multiple life sciences companies and worked as an investment banker focused on the life sciences industry, Dr. Papadopoulos brings to our Board of Directors a firsthand understanding of the demands of establishing, growing and running life sciences businesses.

– Audit

– Finance

– Science and Technology

– BG Medicine, Inc.

– Exelixis, Inc. (Chair)

– Regulus Therapeutics, Inc. (Chair)

– None

Mr. Posner, 56, has served as one of our directors since 2008. Mr. Posner has been a private investor since March 2008 and is the President of Point Rider Group LLC, a consulting and advisory services firm serving predominantly the financial services industry, as well as institutional investors seeking to make control investments in that industry. From 2005 to March 2008, Mr. Posner served as the President, Chief Executive Officer and co-Chief Investment Officer of ClearBridge Advisors LLC, an asset management company and a wholly-owned subsidiary of Legg Mason. Prior to that, Mr. Posner co-founded Hygrove Partners LLC, a private investment fund, in 2000 and served as its Managing Partner for five years. He served as a portfolio manager and an analyst at Fidelity Investments, a financial services company, from 1987 to 1996 and, from 1997 to 1999, at Warburg Pincus Asset Management/Credit Suisse Asset Management where he also served as co-Chief Investment Officer and Director of Research. Mr. Posner also serves as a director of AQR Funds and Arch Capital Group Ltd., a specialty insurance and reinsurance provider.

Given his substantial experience as a leading institutional investment manager and advisor, Mr. Posner brings a professional investor’s perspective and significant management and financial expertise that are valuable to our Board of Directors as it oversees our strategy for enhancing stockholder value.

– Finance (Chair)

– Audit

– Corporate Governance

– AQR Funds

– Arch Capital Group Ltd.

– BG Medicine, Inc.

– Bioverativ Inc. (Chair)

14

Dr. Rowinsky, 61, has served as one of our directors since 2010. He has served as President of RGenix, Inc., a privately-held life sciences company, since November 2015 and as its Executive Chairman since December 2016. Since June 2016, Dr. Rowinsky has also been the Chief Scientific Officer of Clearpath Development Co., which rapidly advances development stage therapeutic assets to pre-defined human proof-of-concept milestones. From January 2012 to November 2015, Dr. Rowinsky was the Head of Research and Development and Chief Medical Officer of Stemline Therapeutics, Inc., a biotechnology company focusing on the discovery and development of therapeutics targeting cancer stem cells. Dr. Rowinsky is an Adjunct Professor of Medicine at New York University and has been an independent consultant since January 2010. Prior to that, he was the Chief Medical Officer of Primrose Therapeutics, Inc., a start-up biotechnology company focusing on the development of therapeutics for polycystic kidney disease, from August 2010 until its acquisition in September 2011. From 2005 to December 2009, he served as the Chief Medical Officer and Executive Vice President of ImClone Systems Incorporated, a life sciences company. From 1996 to 2004, Dr. Rowinsky held several positions at the Cancer Therapy & Research Center’s Institute for Drug Development, including Director of the Institute and Director of Clinical Research. During that time, he held the SBC Endowed Chair for Early Drug Development and Clinical Professor of Medicine at the University of Texas Health Science Center at San Antonio. From 1988 to 1996, Dr. Rowinsky was an Associate Professor of Oncology at the Johns Hopkins School of Medicine and on the staff of the Johns Hopkins Hospital. Dr. Rowinsky serves as a director of Fortress Biotech Inc., a biopharmaceutical company, and Verastem, Inc., a biopharmaceutical company.

Dr. Rowinsky has extensive research and drug development experience and broad scientific and medical knowledge.

– Compensation and Management Development

– Corporate Governance

– Science and Technology

– Fortress Biotech Inc.

– Verastem, Inc.

– BIND Therapeutics, Inc.

– Navidea Biopharmaceuticals, Inc.

15

Ms. Schenk, 73, served as a director of the Company from 1995 to 2003 during the period the Company was operated as IDEC Pharmaceuticals, and has served as a director since 2003 following IDEC’s merger with Biogen, Inc. Ms. Schenk is an attorney and consultant in private practice with extensive public policy and business experience. She is also a member of the Board of Overseers of the Scripps Research Institute, a director of the California High Speed Rail Authority Board and a trustee of the University of California, San Diego Foundation. From 1999 to 2003, she served as Chief of Staff to the Governor of California, during which time she led the effort to create the Institutes for Science and Innovation at the University of California. She headed the State’s Executive Branch risk management team post 9/11 and during the California energy crisis. From 1993 to 1995, Ms. Schenk was a Member of the United States House of Representatives, representing San Diego, California and served on the House Energy & Commerce Committee with a special emphasis on biotechnology. From 1980 to 1983, she was the California Secretary of Business, Transportation and Housing during which time she formed the California Commission on Industrial Innovation. Ms. Schenk is a member of the Board of Directors of Sempra Energy, an energy services and development company, and serves on the Compensation Committee, the Executive Committee and is the Chair of the Environmental Health, Safety and Technology Committee. Ms. Schenk is also a National Association of Corporate Directors (NACD) Board Leadership Fellow, a member of the NACD Advisory Council on Risk Oversight and a Fellow of the UCLA Luskin School of Public Affairs. In 2017 Ms. Schenk was selected as an NACD Directorship 100 honoree.

Ms. Schenk’s strong public policy, government, legal and private sector experience provides vital insights to our Board of Directors about significant issues affecting the highly regulated life sciences industry. She brings public sector operations and management expertise to our Board of Directors. She has demonstrated her commitment to boardroom excellence by completing the NACD’s comprehensive program of study for corporate directors. She supplements her skill sets through ongoing engagement with the director community and access to leading practices.

– Risk (Chair)

– Compensation and Management Development

– Sempra Energy

– None

16

Dr. Sherwin, 69, has served as one of our directors since 2010. Dr. Sherwin currently divides his time between advisory work in the life sciences industry and patient care and teaching in his specialty of medical oncology. He is a Clinical Professor of Medicine at the University of California, San Francisco and a volunteer Attending Physician in Hematology-Oncology at the Zuckerberg San Francisco General Hospital. Dr. Sherwin also currently serves as a venture partner with Third Rock Ventures, LLC. Dr. Sherwin previously served as the Chairman of Ceregene, Inc., a life sciences company that he co-founded, from 2001 until its acquisition by Sangamo Biosciences, Inc. in 2013. He was also a co-founder and chairman of Abgenix, Inc., an antibody company which was acquired by Amgen Inc. in 2006. From 1990 to October 2009, he served as the Chief Executive Officer of Cell Genesys, Inc., a life sciences company, and was its Chairman from 1994 until the company’s merger with BioSante Pharmaceuticals, Inc. (now Ani Pharmaceuticals, Inc.) in October 2009. Prior to that, he held various positions at Genentech, Inc., a life sciences company, most recently as Vice President, Clinical Research. Dr. Sherwin is a member of the Boards of Directors of Aduro Biotech, Inc. and Neurocrine Biosciences, Inc., both of which are clinical-stage life sciences companies.

Dr. Sherwin has extensive knowledge of the life sciences industry and brings more than 30 years of experience in senior leadership positions at large and small publicly traded life sciences companies to our Board of Directors.

– Finance

– Risk

– Science and Technology

– Aduro Biotech, Inc.

– Neurocrine Biosciences, Inc.

– Biosante Pharmaceuticals, Inc.

– Rigel Pharmaceuticals, Inc.

– Verastem, Inc.

– Vical, Inc.

17

Mr. Vounatsos, 56, has served as our Chief Executive Officer and one of our directors since January 2017. Prior to that, from April 2016 until his appointment as our Chief Executive Officer, he served as our Executive Vice President, Chief Commercial Officer. Prior to joining Biogen, Mr. Vounatsos spent 20 years at Merck & Co., Inc., a pharmaceutical company, where he most recently served as President, Primary Care, Customer Business Line and Merck Customer Centricity. In this role, he led Merck’s global primary care business unit, a role which encompassed Merck’s cardiology-metabolic, general medicine, women’s health and biosimilars groups and developed and instituted a strategic framework for enhancing the company’s relationships with key constituents, including the most significant providers, payers and retailers and the world’s largest governments. Mr. Vounatsos previously held leadership positions across Europe and in China for Merck. Prior to that, Mr. Vounatsos held management positions at Ciba-Geigy. Mr. Vounatsos received his C.S.C.T. certificate in Medicine from the Universite Victor Segalen, Bordeaux II, France, and his M.B.A. from the HEC School of Management in Paris.

Mr. Vounatsos has significant knowledge and experience with respect to the biotechnology, healthcare and pharmaceutical industries, a comprehensive leadership background resulting from service as an executive in the pharmaceutical industry and studied medicine as part of his educational background.

– None

– None

– None

18

Committees and Meetings

Our Board of Directors met 16 times in 2017. Our Board of Directors also has six standing committees. The principal functions of each committee, the committee composition in 2017 and number of meetings held in 2017 are described in the table below. The Chair of each committee periodically reports to our Board of Directors on committee deliberations and decisions. Each committee’s charter is posted on our website, www.biogen.com, under the “Corporate Governance” subsection of the “Investors” section of the website. Also posted there are our Corporate Governance Principles, which, together with our committee charters, comprise our governance framework.

19

Director Compensation

This section describes our compensation program for our non-employee directors and shows the compensation paid to or earned by our non-employee directors during 2017. Mr. Vounatsos, our Chief Executive Officer, receives no compensation for his service on our Board of Directors. George A. Scangos, Ph.D., our former Chief Executive Officer and a former member of our Board of Directors, received no compensation for his service on our Board from January 1, 2017 through January 6, 2017.

Retainers, Meeting Fees and Expenses

Effective July 1, 2017, our Board of Directors amended our non-employee director compensation program to increase the annual retainer for the independent Chairman of the Board from $50,000 to $75,000. The annual retainers and meeting fees for our non-employee directors were otherwise unchanged from 2016. The following table presents the annual retainers and meeting fees for all non-employee members of our Board of Directors in effect as of December 31, 2017:

20

2017 Director Compensation

Notes to the 2017 Director Compensation Table

22

Director Equity Outstanding at 2017 Fiscal Year-End

The following table summarizes the equity awards that were outstanding as of December 31, 2017, for each of the non-employee directors serving during 2017.

Notes to the Director Equity Outstanding at 2017 Fiscal Year-End Table

Board Risk Oversight

Our Board of Directors believes that a fundamental part of risk management is understanding the risks that we face, monitoring these risks and adopting appropriate control and mitigation of these risks. As stated in our Corporate Governance Principles, our Board and its committees are responsible for “reviewing the Company’s significant risk exposures and steps taken by management to monitor and mitigate such exposure”. We also have a separate Risk Committee of our Board that assists our Board “in its oversight of management’s exercise of its responsibility to assess and manage risk associate with the Company’s business and operations.”

Our Board oversees the management of material risks facing the Company. Biogen is committed to fostering a company culture of risk-adjusted decision-making without constraining reasonable risk-taking and innovation. Our Board and its committees oversee our efforts to foster this culture. Our Board regularly receives information about our material strategic, operational, financial and compliance risks and management’s response to, and mitigation of, such risks. In addition, our risk management systems, including our risk assessment processes, internal control over financial reporting, compliance programs and internal and external auditing procedures, are designed to inform management and our Board about our material risks. As part of its risk oversight function, our Board and its committees review this framework, its operation and our strategies for generating long-term value for our stockholders to ensure that such strategies will not motivate management to take excessive risks.

In determining the allocation of risk oversight responsibilities, our Board and its committees generally oversee material risks within their identified areas of concern. Our Board and each of its committees meet regularly with management to ensure that management is exercising its responsibility to identify relevant risks and is adequately assessing, monitoring and taking appropriate action to mitigate risk. In the event a committee receives a report from members of management on areas of material risk to the Company, the Chair of the relevant committee reports on the discussion to the full Board of Directors at the next Board of Directors meeting. This enables our Board and its committees to coordinate their oversight of risk and identify risk interrelationships.

23

Our independent Chairman of the Board promotes effective communication and consideration of matters presenting significant risks to the Company through his role in developing our Board’s meeting agendas, advising committee chairs, chairing meetings of the independent directors and facilitating communications between independent directors and our Chief Executive Officer.

A summary of the key areas of risk oversight responsibility of our Board and each of its committees is set forth below:

Compensation Risk Assessment

The Compensation Discussion and Analysis (CD&A) section of this Proxy Statement describes our compensation policies, programs and practices for our named executive officers. Our goal-setting, performance assessment and compensation decision-making processes described in the CD&A apply to all employees. We offer a limited number of short-term cash incentive plans, with employees eligible for either our annual bonus plan or a sales incentive compensation plan. No employee is eligible to participate in more than one cash incentive plan at any time. Our annual bonus plan is consistently maintained for all participants globally, with the same Company performance goals, payout levels (as a percentage of target) and administrative provisions regardless of the participant’s job level, location or function in the Company. We also have a long-term incentive program that provides different forms of awards depending upon an employee’s level, but is otherwise consistent throughout the Company.

In the CD&A, we describe the risk-mitigation controls for our compensation programs. These controls include Compensation Committee review and approval of the design, goals and payouts under our annual bonus plan and long-term incentive program and each executive officer’s compensation (or, in the case of our Chief Executive Officer’s compensation, a recommendation of that compensation to our Board for its approval). In addition, we review the processes, controls and design of our sales incentive compensation plans. Based on our assessment, we believe that, through a combination of risk-mitigating features and incentives guided by relevant market practices and Company-wide goals, our compensation policies, programs and practices do not create risks that are reasonably likely to have a material adverse effect on the Company.

24

Audit Committee Report

26

Audit and Other Fees

Policy on Pre-Approval of Audit and Non-Audit Services

27

This Compensation Discussion and Analysis (CD&A) describes our compensation strategy, philosophy, policies and practices underlying our executive compensation programs for 2017. It also provides information regarding the manner and context in which compensation was earned by and awarded to our 2017 named executive officers listed below, whom we refer to collectively as “named executive officers” or “NEOs”.

29

Financial Performance

The following chart provides a summary of our financial performance for 2017 compared to 2016:

A reconciliation of our GAAP to Non-GAAP financial measures is provided in Appendix A to this Proxy Statement.

Product and Pipeline Developments

Approvals

30

Clinical Trials

Business Development

Capital Allocation

31

Leadership Team

At the core of what we do are our people and our leaders. As a result, our goal is to find top-tier talent with the skills necessary to imagine and lead us into the future. We advanced this goal in 2017 by appointing several new executives in key roles. These appointments included:

Other Notable Achievements in the Workplace and Community

32

Total Stockholder Return

2017 Executive Compensation Programs and Pay-for-Performance Alignment

We believe our executive compensation programs are effectively designed and have worked well to implement a pay-for-performance culture that is aligned with the interests of our stockholders. In 2017 our executive compensation programs consisted of base salary, short- and long-term incentives and other benefits.

91% of our CEO’s and 84% of our other current NEOs’ 2017 target compensation was performance-based and at-risk.

33