(BIOGEN IDEC LOGO) [b68103bib6810300.gif]
EXHIBIT 10.50

      Robert Hamm
  October 15, 2007

Dear Bob:
I am pleased to confirm your promotion to EVP, Pharmaceutical Operations &
Technology. This position will report to James Mullen, CEO & President, and will
be based at our Cambridge, MA facility.
The specific terms of your promotion are as follows.
Promotion Date: The effective date of your promotion is October 12, 2007.
Base Salary: Effective with the date of promotion, your biweekly salary will be
$16,769.24, which is equivalent to an annual salary of $436,000.24.
Short-term-incentive: Your target bonus level under Biogen Idec’s Annual Bonus
Plan will be 50% of your annualized base salary.
Long-term Incentive: You will be granted 2,700 restricted stock units (RSUs).
Assuming your continued employment, these RSUs will vest and convert into shares
of Biogen Idec common stock at the rate of one-third per year over three years,
beginning on the first anniversary of your grant date. The grant date will be
the first trading day of the month following your effective date of promotion.
You will also be granted an option to purchase 6,900 shares of the common stock
of Biogen Idec at an exercise price equal to the closing price of Biogen Idec
stock as reported on the NASDAQ National Market on the grant date. The grant
date will be the first trading day of the month following your effective date of
promotion. The option will have a ten-year term and, assuming your continued
employment, will vest equally over a four-year period at the rate of 25% per
year, starting on the first anniversary of your grant date.
The actual terms of your RSU and stock option grants will be communicated to you
in a separate Notice of Grant. You are considered a “designated employee”, as
defined in the 2005 Omnibus Equity Plan. You are encouraged to carefully review
the 2005 Omnibus Equity Plan Document for information on the implications of
being a designated employee under the Plan, as well as any applicable terms and
conditions of your grants under this program. This document is available on iNet
in the Human Resources Business Area. If you do not have access to the iNet or
would prefer to have a copy mailed to you, please call the HR Helpdesk at
866-824-8444 (toll free), 617-679-3400 or ext. 83400 (internal).
Stock Trading Plan: As an Executive Vice President of the Company, you are
required to enter into a 10b5-1 stock trading plan. A 10b5-1 plan enables you to
buy and sell Biogen Idec securities under pre-specified conditions (e.g., when
the price of Biogen Idec stock reaches a certain price), and allows you to sell
outside of quarterly “trading windows” whether or not you are in possession of
material, nonpublic information. More information on 10b5-1 trading plans can be
found on iNet.
Biogen Idec 14 Cambridge Center Cambridge, MA 02142 Phone 617-679-2000
www.biogenidec.com

 

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Additional Executive Benefits
Vacation: You are entitled to 25 vacation days per year, accrued on a per pay
period basis.
Supplemental Savings Plan: You are entitled to participate in Biogen Idec’s
Supplemental Savings Plan (SSP). This plan allows you to make pre-tax deferrals
of up to 80% of your base salary and up to 100% of your Annual Bonus payment.
Your contributions to this plan may be limited by your contributions towards
other plans (e.g., 401k, ESPP, medical, etc.). If you were not previously
eligible for the SSP, enrollment information will be sent to you shortly.
Life Insurance: You will be provided life insurance coverage equal to three
times your annual base salary, subject to meeting the medical standards stated
in the group term life insurance policy for U.S. employees. Biogen Idec pays the
premium for this insurance. The IRS requires employers to impute the value of
company-paid life insurance for coverage over $50,000. This imputed income will
be displayed on your pay stub.
Severance: Under certain circumstances, you will be entitled to receive
severance benefits. Your severance benefits are explained in detail in the
attached executive severance document.
IRC 280G Excise Taxes: In the event of a Change in Control (as defined in
Section 280G of the Internal Revenue Code), compensation paid to you may trigger
an excise tax (in addition to ordinary income taxes). Biogen Idec will reimburse
you for any excise taxes you incur under IRC 280G as a result of a Change in
Control. This includes gains from the exercise of stock options and vesting of
restricted stock and/or units, as well as the reimbursement for such penalties.
In addition, Biogen Idec will reimburse you for income taxes imposed on the
excise taxes.
Tax Preparation, Financial and Estate Planning: You are entitled to
reimbursement of up to $7,500 per calendar year (January 1 — December 31) for
expenses incurred due to tax preparation, financial and/or estate planning
services, as well as the purchase of tax preparation and/or financial planning
software. To receive reimbursement, copies of receipts/invoices from eligible
service providers should be submitted through the Company’s third party
reimbursement service provider. Such reimbursements are considered taxable
income.
Air Travel Upgrade: You are entitled to fly first class on all U.S.
transcontinental flights (e.g., Boston to San Diego). Overseas flights and other
domestic flights are subject to the same policy as all other employees.

 

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Once you have accepted this offer, please sign and return a copy of this letter
to me. I am confident you will continue to contribute to Biogen Idec’s success
and wish you the best of luck in your new position.

          Sincerely,
      /s/ James C. Mullen       James Mullen      CEO & President       

cc: Craig Schneier

     
/s/ Robert Hamm
  15 Oct 2007
Robert Hamm
  Date

Your employment at Biogen Idec continues to be employment at-will. This means
that just as you are free to leave your employment at any time, with or without
cause or notice, Biogen Idec also has the same right to terminate your
employment at any time, with or without cause or notice.

 

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Executive Severance — Executive Vice President
As an Executive Vice President, you are entitled to severance benefits in the
event your employment is terminated by Biogen Idec other than For Cause or for
reason of death or Disability (as these terms are defined in the Biogen Idec
2005 Omnibus Equity Plan).
Benefits
Your severance benefits are comprised of (i) a lump sum payment (as calculated
below), (ii) upon completion of the appropriate forms, continuation of your
participation in Biogen Idec’s group medical and dental insurance plans, to the
same extent permitted by COBRA and to the same extent such insurance is then
provided to regular employees of Biogen Idec, including payment by you of a
portion of the insurance premiums (i.e., the “Insurance Benefit”) and (iii) the
reasonable cost of up to nine months of executive-level outplacement services
from a recognized provider of such services, at the expense of Biogen Idec (upon
receipt of appropriate documentation).
The lump sum severance payment is calculated as follows:
[9 + (A x 2.5)] x B = lump sum payment

  where:   A is the number of full years of service with Biogen Idec (but A x
2.5 may not exceed 12), and B is the monthly equivalent of your target annual
cash compensation at the time of your termination (i.e., one-twelfth of the sum
of your then annual base salary plus target annual bonus).

The following are examples of how the lump sum payment and Insurance Benefit
Period are determined:

      If your employment with Biogen Idec is terminated after 10 months of
employment, you will receive a lump sum payment equal to nine months of your
target annual cash compensation and continue to participate in Biogen Idec’s
group medical and dental plans for nine months, unless you become eligible to
participate in another employer’s medical and dental plans before that date.
COBRA continuation of medical and dental benefits is available, at your own
expense, for an additional nine months after this nine-month Insurance Benefit
Period.         If your employment with Biogen Idec is terminated after five
years, you will receive a lump sum payment equal to 21 months [9+12] of your
target annual cash compensation and continue to participate in Biogen Idec’s
group medical and dental plans for 21 months, unless you become eligible to
participate in another employer’s medical and dental plans before that date.

If at any time within two years following a Corporate Transaction or Corporate
Change in Control (as these terms are defined in Biogen Idec’s 2005 Omnibus
Equity Plan) your employment is terminated by Biogen Idec or the succeeding
corporate entity, other than For Cause or for reason of death or Disability (as
these terms are defined in Biogen Idec’s 2005 Omnibus Equity Plan), or you
experience an Involuntary Employment Action (defined below) and as a result you
terminate your employment with Biogen Idec or the succeeding corporate entity,
then, regardless of the length of your service with Biogen Idec and the
succeeding corporate entity, and in lieu of the formula set forth above, you
will receive a lump sum payment equivalent to 24 months of your target annual
cash compensation at the time of your termination or at the time of a Corporate
Transaction or Corporate Change in Control, whichever is higher. In addition,
you will be entitled to continue participating in Biogen Idec’s group medical
and dental plans for 24 months, unless you become eligible to participate in
another employer’s medical and dental plans before that date. The term
“Involuntary Employment Action” shall have the definition set forth in Biogen
Idec’s 2005 Omnibus Equity Plan, provided, however, that the term “Corporate
Transaction” used

 

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in that definition shall be deemed to mean either a Corporate Transaction or
Change in Control, as the case may be, and provided also that prior to your
termination of employment you have notified the Chief Legal Counsel or the Head
of Human Resources of Biogen Idec in writing of the basis for your Involuntary
Employment Action, you have given such notice within one year of the
circumstances giving rise to your Involuntary Employment Action and Biogen Idec
does not cure such circumstances within 30 days after the date of your notice.
Delivery of Benefits
Payment and provision of all the benefits provided under this arrangement are
conditioned on your execution and delivery of all necessary forms and an
irrevocable general release in favor of Biogen Idec, in form and substance
reasonably acceptable to Biogen Idec, with respect to any and all claims
relating to your employment and the termination of your employment with Biogen
Idec. If you retire or voluntarily terminate your employment with Biogen Idec,
or Biogen Idec terminates your employment For Cause or for reason of death or
Disability (as these terms are defined in Biogen Idec’s 2005 Omnibus Equity
Plan), or you do not provide the requisite general release, you will not be
eligible to receive the severance benefits described above.
If all other conditions of this arrangement are met, a lump sum payment (less
applicable taxes and other mandatory deductions as required by law) will be paid
to you following the termination of your employment, no later than the first to
occur of: a) 90 days following your termination of your employment with Biogen
Idec and b) March 15 of the year following the calendar year in which
termination of employment occurs, unless you are a “specified employee” as
defined in Section 409A of the Internal Revenue Code of 1986, as amended (i.e.,
“Section 409A”). (If all preconditions to payment, including the delivery of an
irrevocable general release, are not satisfied prior to the earlier of these two
dates, payment to you may be delayed and you may incur additional tax
liabilities under Section 409A.) If you are a “specified employee”, to the
extent required by Section 409A, payment will not be made to you before the date
which is six months after you “separate from service” (or, if earlier, your date
of death or Disability) unless the payment qualifies as excepted welfare
benefits under Section 409A, does not constitute a “deferral of compensation”
under Section 409A or is otherwise not subject to the requirements of
Section 409A.
The Insurance Benefit will continue until the earlier of (i) the date you become
eligible to participate in the medical and dental insurance plan of another
employer or (ii) the date that is [9 + (A x 2.5)] months, but not more than
21 months (or 24 months in the case of a Corporate Transaction or Change in
Control), following the termination of your employment with Biogen Idec (the
“Insurance Benefit Period”). You will have the right, at your own expense, to
continue your participation in Biogen Idec’s group medical and dental insurance
plans at the expiration of the Insurance Benefit Period, pursuant to the
provisions of COBRA, but only for an 18-month period that will be deemed to have
commenced at the start of your severance.
General
Biogen Idec shall administer and shall have the discretionary authority to adopt
rules for the management and operation of this arrangement, to interpret the
provisions of the arrangement and to construe the terms of the severance
arrangement in its sole discretion. The decision of Biogen Idec, or the duly
authorized delegate, is final and conclusive for all purposes.
The severance arrangement may be amended, modified, suspended or terminated by
Biogen Idec at any time; provided that the severance arrangement may not be
amended or terminated without your written consent for a period of two years
following a Corporate Transaction or a Change in Control.

 

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This arrangement is unfunded. This arrangement will benefit and bind Biogen Idec
and its successors and permitted assigns and you and your heirs, executors and
legal representatives. You do not have any right to transfer or assign your
benefits under this arrangement.
This arrangement shall be construed, administered and enforced according to the
laws of the State of Delaware, except to the extent that such laws are preempted
by the federal laws of the United States of America.