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EXHIBIT 4.(C).1
 OPTION PLAN FOR SELECTED MEMBERS OF
HYDROS TOP MANAGEMENT GROUP
 2005  2011
 1.
    
    Background informationThis document comprises a description of the option plan for the Top Management Group in
Hydro, in which
 has been offered to participate.The Option Plan is offered as an incentive to stimulate growth in the value of the
Companys shares. The Companys Board of Directors also places importance on selected
persons having an ownership interest in the Company for as long as they are employed in
a top management position.The Option Plan is offered to members of the Corporate Management Board and other
persons designated by the President and CEO.The Board of Directors in Norsk Hydro ASA (the Company) determines the framework for the
Option Plan, and allots options to the President and CEO. The President and CEO allots
options to the Corporate Management Board and the Top Management Group.The President and CEO, or person authorized by the President and CEO, draws up and
maintains a list of: the persons to whom the plan is currently available, the persons
who are currently taking part in the plan (the Option Holders) and the number of options
allotted to each person; and draws up the necessary routines for the execution of the
Option Plan.The Companys Board of Directors, or person appointed by the Board, shall decide
questions relating to the options allotted to the President and CEO in accordance with
this plan that would otherwise be decided by the President and CEO.2.
    
    The number of options allottedname  is allotted x,x00 options for the year 2005.The allotment and exercise of options does not constitute part of the Option Holders
salary or entitlement to other benefits in accordance with his or her employment
contract. The value of the options or any Profit acquired through this agreement is not
included in the basis for calculating holiday pay. Allotment and exercise of options
does not give any pension rights.The options allotted may not be sold, mortgaged, given away or transferred in any other
way than as determined below.3.
    
    Exercise Price (strike price)The Exercise Price is fixed at NOK 622.




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4.
    
    Exercise of options
 a.
    
    Each option entitles the Option Holder to the difference in Norwegian
kroner between the Hydro shares average market price (share price on the Oslo
Stock Exchange at the end of trading) for the five  5  trading days prior to the
day on which the option is exercised and the Exercise Price, in accordance with the
conditions given below. This entitlement is hereinafter called the Profit.b.
    
    Options may be exercised from and including 1 July, 2008. The last day
for exercising the options is 30 June 2011, after which date, unexercised options
will no longer be valid. Options may be exercised earlier, cf. Section 6 below. The
Option Holder decides when and how many options are to be exercised at any time in
relation to options that he or she is entitled to exercise, also within the limits
delineated in section 4.c.c.
    
    The Option Holder may not exercise options that will result in a Profit
per calendar year that exceeds the Option Holders gross salary excluding bonus and
additional benefits during the same period. This limitation applies in aggregate
for all options allotted from and including the year 2004 regardless of the option
plan, unless otherwise explicitly stated in a new plan.d.
    
    On exercise of an option, the Option Holder is entitled to payment of
the Profit with the deduction of the tax to which the Profit is subject, cf.
section 8, hereinafter called the Net Profit.
 5.
    
    Duty of ownership and investment of the Profit from the Option Plan in Hydro shares for
the duration of employment in the CompanyThe Option Holder is obliged to invest the Net Profit within 6 months after it has been
received in Hydro shares at market price. The duty to invest the Net Profit in Hydro shares does not, however, apply to:
 
    
    The President and CEO, if he has already purchased Hydro shares of a total
market value equivalent to twice his annual salary at this point in time with
previously disbursed Net Profit,
    
    Other members of the Corporate Management Board, if they have already
purchased Hydro shares of a total market value equivalent to their annual salary
at this point in time with previously disbursed Net Profit, or
    
    Option Holders who are not members of the Corporate Management Board, if they
have already purchased Hydro shares of a total market value equivalent to half
their annual salary at this point in time with previously disbursed Net Profit.
 The Option Holder may include other Hydro shares that he or she owns, but which have not
been purchased with Net Profit, cf. the above paragraph, in his or her overall share
portfolio in relation to annual salary, cf. the above paragraph.If the Option Holder needs to purchase shares, his or her portfolio will be assessed at
the time of the purchase of the new shares and be compared with the ownership
requirements related to his or her base salary at the time the option was exercised.The Option Holder should inform CHR when their obligation to buy or to own Hydro shares
has been fulfilled.Hydro shares that are purchased with the Net Profit, and other Hydro shares which
are included in the Option Holders calculation of his or her overall share portfolio in
relation to annual salary, cf. section 5 first and second paragraph, may not be sold,
mortgaged, given away or transferred in any other way for as long as the Option Holder
is employed in Norsk Hydro ASA or in one of its subsidiaries.If the Option Holder transfers to a new position in Hydro, and is thus no longer part of
the Companys Top Management Group for which this and equivalent future plans applies,
the duty to




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own Hydro shares no longer applies. In such cases, the duty to invest the
Net Profit in Hydro shares, cf. the first sentence of the first paragraph of section 5
no longer applies.In particular cases, the Companys President and CEO may waiver the requirement for
investment of the Net Profit in Hydro shares and ownership of Hydro shares.
 6.
    
    Requirements regarding employment relationshipThe main rule is that options are allotted and can only be exercised for as long as the
Option Holder is employed in Norsk Hydro ASA or one of its subsidiaries.If the Option Holders employment relationship ends as a result of
 
    
    the Option Holders death,
    
    injury, disability or illness,
    
    dismissal from the Company/Group as a result of supernumeracy or reorganization,
    
    retirement
    
    ownership of the company/operation in which the Option Holder is employed
changing, excluding demerger, in such a way as Hydro no longer has determining
influence or more than 50% ownership (cf. the Public Limited Companies Act §
1-3),
 the Option Holder (or the Option Holders estate) may exercise the allotted options
within 12 months of the date of retirement, change of ownership or death, regardless of
the condition laid down in the first sentence of section 4.b. Options that are not
exercised within this deadline will automatically become invalid. In the cases listed
above in this paragraph, the Option Holder (or the Option Holders estate) is not
obliged to invest the Net Profit in Hydro shares. The restriction on the amount of
Profit in relation to salary, cf. section 4.c. applies in so far as the total Profit on
the exercise of options in the 12 month period in question may not exceed the Option
Holders gross annual salary, excluding bonus and additional benefits, at the time of
retirement/change in company ownership. In case of demerger, the rules defined in this
paragraph applies, unless the Board of Directors of Norsk Hydro ASA decides differently.
 If the Option Holder
 
    
    resigns from the Company (or subsidiary), or
    
    is dismissed as a result of breach of duty or other unacceptable
circumstances on the part of the Option Holder, and the dismissal is accepted by
the Option Holder or is legally determined as valid,
 all allotted options that have not been exercised will be withdrawn, and this option
plan will no longer apply for the Option Holder in question, with immediate effect. In
such cases, the Option Holder will not have any entitlement to compensation for the loss
of the options.
 7.
    
    Changes in the company conditions
 In the event of any company law changes to Norsk Hydro ASA, such as demerger, merger,
reduction of capital, increase of capital, share split or share splice, the number of
options allotted and/or the Exercise Price shall be adjusted as the Companys Board
deems to reasonably maintain the principle of Option Holders having exposure to a value
development reflecting that of the shareholders. Option Holders shall be notified of any
such adjustment.
 8.
    
    Tax issues
 The Net Profit is included as Profit for deduction of marginal tax as deemed to be
relevant for the Option Holder by the Company.
 The Profit gained on the exercise of an option shall be treated as the top income the
Option Holder earns in the tax year in question, and will therefore normally be subject
to the highest marginal tax. The Option Holder shall report his or her marginal tax rate
on exercising an option. The Company can, however, freely assess what marginal tax rate
shall be applied.




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It is the sole risk of the Option Holder should it later be found that the wrong tax
rate was applied. Any reimbursed tax or tax arrears shall not have any effect on the
Option Holders obligation to purchase Hydro shares for the Net Profit stipulated or to
his or her obligation to own Hydro shares.The Option Holder is personally responsible for any tax obligation that may arise from
the Option Plan. The tax effect of allotment, holding and exercise of options will vary
between different jurisdictions. The Option Holder is advised to seek personal tax
advice on these questions.In jurisdictions where this is required, the Company (or subsidiary) will deduct tax in
advance. Where advance tax deduction is not practiced, the whole Profit will be paid to
the Option Holder, and the same obligation to invest the Net Profit will apply, cf. the
first paragraph of section 5.9.
    
    Stock exchange rulesThe Option Holder is responsible for ensuring that his or her options are exercised in
accordance with stock exchange and securities legislation, and that the exercise of
options is not in conflict with rules on inside trading and trading restrictions during
certain periods. The Option Holder must ensure that he or she meets the obligation to
report to the Oslo Stock Exchange and other relevant authorized market places in
connection with the exercise of an option.To assist the Option Holder, The President and CEO, or person authorized by the
President and CEO, shall draw up routines for reporting in connection with exercising
options, investment of the Net Profit in Hydro shares and sale of the Option Holders shares in Hydro.
    for Norsk Hydro ASA
    
    Option HolderEivind Reiten
    
    xxxxxx xxxxxx