Riverbed Technology (RVBD)

SECTION 4. ENROLLMENT AND PARTICIPATION.

(a) Offering Periods. While the Plan is in effect, the Committee shall determine the duration and commencement date of each Offering Period, provided that an Offering Period shall in no event be longer than 27 months. Offering Periods may be consecutive or overlapping.

(b) Accumulation Periods. While the Plan is in effect, the Committee shall determine the duration and commencement date of each Accumulation Period, provided that an Accumulation Period shall in no event end later than the close of the Offering Period in which it begins. Accumulation Periods shall be consecutive.

(c) Enrollment. In the case of any individual who qualifies as an Eligible Employee on the first day of any Offering Period, he or she may elect to become a Participant on such day by filing the prescribed enrollment form with the Company. The enrollment form shall be filed at the prescribed location not later than the commencement date of such Offering Period.

(d) Duration of Participation. Once enrolled in the Plan, a Participant shall continue to participate in the Plan until he or she:

(i) Reaches the end of the Accumulation Period in which his or her employee contributions were discontinued under Section 5(c) or 9(b);

(ii) Withdraws from the Plan under Section 6(a); or

(iii) Ceases to be an Eligible Employee.

A Participant whose employee contributions were discontinued automatically under Section 9(b) shall automatically resume participation at the beginning of the earliest Accumulation Period ending in the next calendar year, if he or she then is an Eligible Employee. In all other cases, a former Participant may again become a Participant, if he or she then is an Eligible Employee, by following the procedure described in Subsection (c) above.

(e) Applicable Offering Period. For purposes of calculating the Purchase Price under Section 8(b), the applicable Offering Period shall be determined as follows:

(i) Once a Participant is enrolled in the Plan for an Offering Period, such Offering Period shall continue to apply to him or her until the earliest of (A) the end of such Offering Period, (B) the end of his or her participation under Subsection (d) above or (C) enrollment for a subsequent Offering Period under Paragraph (ii), (iii) or (iv) below, provided that the Committee has determined that there will be a subsequent Offering Period.

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(ii) In the event that the Fair Market Value of Stock on the first trading day in the Offering Period for which the Participant is enrolled is higher than on the first trading day in any subsequent Offering Period, the Participant shall automatically be enrolled for such subsequent Offering Period.

(iii) If Section 14(b) applies, the Participant shall automatically be enrolled for a new Offering Period.

(iv) Any other provision of the Plan notwithstanding, the Company (at its sole discretion) may determine prior to the commencement of any new Offering Period that all Participants shall be enrolled for such new Offering Period.

(v) When a Participant reaches the end of an Offering Period but his or her participation is to continue, then such Participant shall automatically be enrolled for the Offering Period that commences immediately after the end of the prior Offering Period.