Exhibit 10.1

Data Domain, Inc. 2009 Executive Bonus Plan

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DATA DOMAIN, INC. 2009 EXECUTIVE BONUS PLAN

1. Effective Date and Term. This 2009 Bonus Plan (the “Plan”) was adopted by the
Compensation Committee (the “Committee”) of the Board of Directors of Data
Domain, Inc. (the “Company”). The Plan is effective for fiscal year 2009. The
Plan is for the benefit of individuals who are officers of the Company (the
“Officers”). Any other bonus plan applicable to Officers previously approved by
the Committee is hereby terminated.

2. Administration. The Committee administers the Plan and adopts rules and
regulations to implement the Plan. The decisions of the Committee are final and
binding on all parties who have an interest in the Plan.

3. Eligibility. Participation in the Plan is limited to Executive Staff Members.
Participation in the Plan is effective on the day the participant starts in a
bonus-eligible job. Bonus payments will be prorated based on the number of days
the participant is employed by the Company during the fiscal quarter. Bonus
payments will be prorated for participants who become eligible after the start
of a fiscal quarter or for participants who are on a leave of absence or
sabbatical for all or part of a fiscal quarter. A participant may be removed
from the Plan at any time and for any reason, at the Company’s discretion,
regardless of whether he or she remains an officer or employee of the Company.

4. Determination of Amounts. The Plan may provide a quarterly cash bonus that is
paid based on the achievement of pre-determined Company performance objectives
and individual performance factors. The amount of each participant’s quarterly
bonus is determined as follows:

(a) An annual target bonus amount is assigned to the participant by the
Committee as soon as reasonably practicable after the beginning of a fiscal year
or, if later, at the time of his or her hiring. The annual target bonus amount
shall be a percentage of base salary and may be modified from time to time
thereafter by the Committee. The quarterly target bonus amount is equal to 20%
of the annual target bonus amount. 20% of the annual target bonus will be paid
following the close of fiscal Q4 and will be determined based upon achievement
of (revenue or bookings as applicable) for FY09.

(b) The quarterly bonus is determined on the basis of plan achievement, and with
respect to each participant is based on revenue and/or bookings as determined by
the Committee.

(c) Calculation of quarterly bonuses will be based on percentage of plan
achievement (revenue or bookings as applicable). Payouts of bonuses will begin
paying at 80% plan achievement and scale linearly to 100% at 100% plan
achievement. Over-achievement of goals beyond 100% and up to 150% of plan
accelerates bonus payout at the rate of 2:1, that is, for every 1%
overachievement the bonus accelerates by 2% of the total bonus amount. From 151%
of overachievement and beyond, the bonus payout decelerates to 1.5% per percent
of overachievement.

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(d) When the actual amount of plan achievement for a fiscal quarter has been
determined, the achievement score is calculated. This score is multiplied by
each participant’s quarterly target bonus amount. The result is the
participant’s tentative quarterly bonus, based on financial measures (the
“Tentative Bonus”).

(e) After the close of each fiscal quarter, the Committee at its discretion may
increase or reduce any Tentative Bonus, based on criteria other than revenue and
sales (including the Company’s achievement of its financial plan in areas other
than sales or revenue, particularly operating profit and gross margins, and the
individual’s achievement of quarterly objectives).

(f) The Committee may adjust the amount of the Company’s quarterly revenue or
sales figures to exclude extraordinary items.

5. Payment of Bonuses. Payment of the quarterly cash bonus (if any) is targeted
for the payroll date of April 30, July 31, October 31 and January 31.
Adjustments to this payment schedule may be made as business conditions require.
Bonus payments, however, shall be paid no later than the later of (i) March 15
of the calendar year following the year with respect to which the bonus is
earned or (ii) the fifteenth day of the third month following the end of the
Company fiscal year with respect to which the bonus is earned.

6. Employment Requirement. The participant must be employed by the Company at
the time of the bonus payment to receive the quarterly cash bonus for the first,
second and third quarters of FY09. The participant must be employed by the
Company as of December 31, 2009 to be eligible to receive the quarterly cash
bonus for the fourth quarter of FY09 and the FY09 annual cash bonus.

7. Modification or Termination of the Plan. The Committee reserves the right to
modify, suspend or terminate this Plan at any time. Should an acquisition or
significant business initiative change the operating plan, this Plan may be
modified or a new plan may go into effect at the start of the fiscal quarter
following the event.

8. Benefits Unfunded. No amounts awarded or accrued under this Plan will be
funded, set aside or otherwise segregated prior to payment. The obligation to
pay the bonuses awarded hereunder will at all times be an unfunded and unsecured
obligation of the Company. Plan participants will have the status of general
creditors and must look solely to the general assets of the Company for the
payment of their bonus awards.

9. Benefits Nontransferable. No Plan participant will have the right to
alienate, pledge or encumber his or her interest in this Plan, and such interest
will not (to the extent permitted by law) be subject in any way to the claims of
the participant’s creditors or to attachment, execution or other process of law.

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10. No Employment Rights. No action of the Company in establishing the Plan, no
action taken under the Plan by the Committee and no provision of the Plan itself
will be construed to grant any person the right to remain in the employ of the
Company or its subsidiaries for any period of specific duration. Rather, each
employee is employed “at will,” which means that either the employee or the
Company may terminate the employment relationship at any time and for any
reason, with or without cause.