EXHIBIT A
Joint Filing Agreement
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In accordance with Rule 13d-1(f) under the Securities Exchange Act of
1934, as amended, each of the persons named below agrees to the joint filing of
a Statement on Schedule 13D (including amendments thereto) with respect to the
common stock, no par value, of Gentle Dental Service Corporation, a Washington
corporation and further agrees that this Joint Filing Agreement be included as
an exhibit to such filings provided that, as contemplated by Section
13d-1(f)(l)(ii), no person shall be responsible for the completeness or
accuracy of the information concerning the other persons making the filing,
unless such person knows or has reason to believe that such information is
inaccurate. This Joint Filing may be executed in any number of counterparts,
all of which together shall constitute one and the same instrument.
Sprout Growth II, L.P.
by: DLJ Capital Corporation
its: Managing General Partner
By: /s/ Xxxxxxxx X. Xxxxx
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Name: Xxxxxxxx X. Xxxxx
Title: Secretary
DLJ Growth Associates II, L.P.
by: DLJ Growth Associates (II), Inc.
its: General Partner
By: /s/ Xxxxxxxx X. Xxxxx
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Name: Xxxxxxxx X. Xxxxx
Title: Secretary and Treasurer
DLJ Growth Associates (II), Inc.
By: /s/ Xxxxxxxx X. Xxxxx
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Name: Xxxxxxxx X. Xxxxx
Title: Secretary and Treasurer
Sprout Capital VII, L.P.
by: DLJ Capital Corporation
its: Managing General Partner
By: /s/ Xxxxxxxx X. Xxxxx
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Name: Xxxxxxxx X. Xxxxx
Title: Secretary
DLJ Associates VII, L.P.
by: DLJ Associates VII, Inc.
its: General Partner
By: /s/ Xxxxxxxx X. Xxxxx
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Name: Xxxxxxxx X. Xxxxx
Title: Secretary and Treasurer
DLJ Capital Associates VII, Inc.
By: /s/ Xxxxxxxx X. Xxxxx
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Name: Xxxxxxxx X. Xxxxx
Title: Secretary
The Kroon 1994 Limited Partnership
by: Xxxxxxx X. Xxxxx
its: General Partner
By: /s/ Xxxxxx X. Xxxxxxxxx
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Name: Xxxxxx X. Xxxxxxxxx
Title: Attorney-in-Fact
Xxxxxxx X. Xxxxxxx
By: /s/ Xxxxxx X. Xxxxxxxxx
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Name: Xxxxxx X. Xxxxxxxxx
Attorney-in-Fact
Xxxxxxxx X. Xxxxxxx
By: /s/ Xxxxxx X. Xxxxxxxxx
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Name: Xxxxxx X. Xxxxxxxxx
Attorney-in-Fact
Xxxxxx X. Xxxxx
By: /s/ Xxxxxx X. Xxxxxxxxx
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Attorney-in-Fact
Xxxxxx Xxxxx
By: /s/ Xxxxxx X. Xxxxxxxxx
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Name: Xxxxxx X. Xxxxxxxxx
Attorney-in-Fact
Xxxxx X. Xxxxxxx
By: /s/ Xxxxxx X. Xxxxxxxxx
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Name: Xxxxxx X. Xxxxxxxxx
Attorney-in-Fact
The JHT 1994 Limited Partnership
by: Xxxxx X. Xxxxxx
its: General Partner
By: /s/ Xxxxxx X. Xxxxxxxxx
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Name: Xxxxxx X. Xxxxxxxxx
Title: Attorney-in-Fact
Xxxxxxxx X. XxXxxxx
By: /s/ Xxxxxx X. Xxxxxxxxx
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Name: Xxxxxx X. Xxxxxxxxx
Title: Attorney-in-Fact
Xxxxx X. Meadow
By: /s/ Xxxxxx X. Xxxxxxxxx
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Name: Xxxxxx X. Xxxxxxxxx
Attorney-in-Fact
Xxxxxx X. Xxxxxxxxx
By: /s/ Xxxxxx X. Xxxxxxxxx
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Name: Xxxxxx X. Xxxxxxxxx
Xxxxx X. Xxxxxx
By: /s/ Xxxxxx X. Xxxxxxxxx
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Name: Xxxxxx X. Xxxxxxxxx
Attorney-in-Fact
Xxx Xxxxx
By: /s/ Xxxxxx X. Xxxxxxxxx
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Name: Xxxxxx X. Xxxxxxxxx
Attorney-in-Fact
Xxxxxxx X. Xxxxx
By: /s/ Xxxxxx X. Xxxxxxxxx
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Name: Xxxxxx X. Xxxxxxxxx
Attorney-in-Fact
Xxxx Xxxx Xxxxx
By: /s/ Xxxxxx X. Xxxxxxxxx
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Name: Xxxxxx X. Xxxxxxxxx
Attorney-in-Fact
DLJ Capital Corporation
By: /s/ Xxxxxxxx X. Xxxxx
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Name: Xxxxxxxx X. Xxxxx
Title: Secretary and Treasurer
Xxxxxxxxx, Xxxxxx & Xxxxxxxx, Inc.
By: /s/ Xxxxxxxx X. Xxxxx
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Name: Xxxxxxxx X. Xxxxx
Title: Vice President and Secretary
The Equitable Companies Incorporated
By: /s/ Xxxxx X. Xxxxxxxx
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Name: Xxxxx X. Xxxxxxxx
Title: Senior Vice President and Controller
AXA
Finaxa
AXA Assurances I.A.R.D. Mutuelle
AXA Assurances Vie Mutuelle
AXA Courtage Assurance Mutuelle
AXA Conseil Vie Assurance Mutuelle
Xxxxxx Xxxxxx, as AXA Voting Trustee
Xxxxxxx Xxxxxxx, as AXA Voting Trustee
Xxxxx xx Xxxxxxxx-Tonnerre, as AXA Voting Trustee
Signed on behalf of each of the above
By: /s/ Xxxxx X. Xxxxxxxx
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Name: Xxxxx X. Xxxxxxxx
Title: Attorney-in-fact