Common use of COUNTERSIGNATURE Clause in Contracts

COUNTERSIGNATURE. This Amendment shall become effective only when it shall have been executed by Seller and Buyer. This Amendment is executed as a sealed instrument under the laws of the Commonwealth of Massachusetts as of the date first written above. SELLER: BUYER: ASPEN TECHNOLOGY, INC. SILICON VALLEY BANK By: /s/ Xxxxxxx X. Xxxxxx By: /s/ Xxxxxxx Xxxxxxx Name: Xxxxxxx X. Xxxxxx Name: Xxxxxxx Xxxxxxx Title: Chief Financial Officer Title: Senior Vice President

COUNTERSIGNATURE. This Amendment shall become effective only when it shall have been executed by Seller and Buyer. This Amendment is executed as a sealed instrument under the laws of the Commonwealth of Massachusetts as of the date first written above. SELLER: BUYER: ASPEN TECHNOLOGY, INC. SILICON VALLEY BANK By: /s/ Xxxxxxx X. Xxxxxx By: /s/ Xxxxxxx Xxxxxxx Name: Xxxxxxx X. Xxxxxx Name: Xxxxxxx Xxxxxxx Title: Chief Financial Officer Title: Senior Vice PresidentBy: Name: Title:

COUNTERSIGNATURE. This Amendment shall become effective only when it shall have been executed by Seller Borrower and BuyerBank. This Amendment is executed as a sealed instrument under the laws of the Commonwealth of Massachusetts as of the date first written above. SELLERBORROWER: BUYERBANK: ASPEN TECHNOLOGY, INC. ARBINET CORPORATION SILICON VALLEY BANK By: /s/ Xxxxxxx X. Gxxx Xxxxxx By: /s/ Xxxxxxx Xxxxxxx Axxxx X. Xxxxxxxxxx Name: Xxxxxxx X. Gxxx Xxxxxx Name: Xxxxxxx Xxxxxxx Axxxx X. Xxxxxxxxxx Title: Chief Financial Officer CFO Title: Senior Vice President

COUNTERSIGNATURE. This Amendment shall become effective only when it shall have been executed by Seller and Buyer. This Amendment is executed as a sealed instrument under the laws of the Commonwealth of Massachusetts as of the date first written above. SELLER: BUYER: ASPEN TECHNOLOGY, INC. SILICON VALLEY BANK BANK, doing business as SILICON VALLEY EAST By: /s/ Xxxxxxx XXXXXXX X. Xxxxxx XXXX By: /s/ Xxxxxxx Xxxxxxx XXXX XXXX Name: Xxxxxxx X. Xxxxxx Xxxx Name: Xxxxxxx Xxxxxxx Title: Chief Financial Officer Xxxx Xxxx Title: Senior VP and CFO Title: Vice PresidentPresident QuickLinks

COUNTERSIGNATURE. This Amendment shall become effective only when it shall have been executed by Seller and Buyer. This Amendment is executed as a sealed instrument under the laws of the Commonwealth of Massachusetts as of the date first written above. SELLER: BUYER: ASPEN TECHNOLOGY, INC. SILICON VALLEY BANK By: /s/ Xxxxxxx X. Xxxxxx By: /s/ Xxxxxxx Xxxxxxx Name: Xxxxxxx X. Xxxxxx Name: Xxxxxxx Xxxxxxx Title: Chief Financial Officer Title: Senior Vice President:

COUNTERSIGNATURE. This Amendment shall become effective only when it shall have been executed by Seller and Buyer. This Amendment is executed as a sealed instrument under the laws of the Commonwealth of Massachusetts as of the date first written above. SELLER: BUYER: ASPEN TECHNOLOGY, INC. SILICON VALLEY BANK By: /s/ Xxxxxxx X. Xxxxx Xxxxxx By: /s/ Xxxxxxx Xxxxxxx Xxxxxx Xxxx Name: Xxxxxxx X. Xxxxx Xxxxxx Name: Xxxxxxx Xxxxxxx Xxxxxx Xxxx Title: Chief Financial Officer Treasurer Title: Senior Vice PresidentPresident By: /s/ Xxxx X. Xxxxxxxx Name: Xxxx Xxxxxxxx Title: CFO

COUNTERSIGNATURE. This Amendment shall become effective only when it shall have been executed by Seller and Buyer. This Amendment is executed as a sealed instrument under the laws of the Commonwealth of Massachusetts as of the date first written above. SELLER: BUYER: ASPEN TECHNOLOGY, INC. SILICON VALLEY BANK By: /s/ Xxx X. Xxxxxxx X. Xxxxxx By: /s/ Xxxxxxx Xxxx X. Xxxx Name: Xxx Xxxxxxx Name: Xxxxxxx Xxxx X. Xxxxxx Name: Xxxxxxx Xxxxxxx Xxxx Title: Chief Financial Officer VP Treasurer Title: Senior Vice President

COUNTERSIGNATURE. This Amendment shall become effective only when it shall have been executed by Seller and Buyer. This Amendment is executed as a sealed instrument under the laws of the Commonwealth of Massachusetts as of the date first written above. SELLER: BUYER: ASPEN TECHNOLOGY, INC. SILICON VALLEY BANK BANK, doing business as SILICON VALLEY EAST By: /s/ Xxxxxxx X. Xxxxxx Xxxx By: /s/ Xxxxxxx Xxxxxxx Name: Xxxxxxx X. Xxxxxx Xxxx Name: Xxxxxxx Xxxxxxx Title: SUP–Chief Financial Officer Title: Senior Vice President840584.1

COUNTERSIGNATURE. This Amendment shall become effective only when it shall have been executed by Seller and Buyer. This Amendment is executed as a sealed instrument under the laws of the Commonwealth of Massachusetts as of the date first written above. SELLER: BUYER: ASPEN TECHNOLOGY, INC. SILICON VALLEY BANK By: /s/ Xxxxxxx X. Xxxx Xxxxxx By: /s/ Xxxxxxx Xxxxxxx Xxxx X. Xxxx Name: Xxxxxxx X. Xxxx Xxxxxx Name: Xxxxxxx Xxxxxxx Xxxx X. Xxxx Title: Chief Financial Officer SUP-CFO Title: Senior Vice PresidentSVP

COUNTERSIGNATURE. This Amendment shall become effective only when it shall have been executed by Seller and Buyer. This Amendment is executed as a sealed instrument under the laws of the Commonwealth of Massachusetts as of the date first written above. SELLER: BUYER: ASPEN TECHNOLOGY, INC. SILICON VALLEY BANK By: /s/ Xxx X. Xxxxxxx X. Xxxxxx By: /s/ Xxxxxxx Xxxxx X. Xxxxx Name: Xxx Xxxxxxx Name: Xxxxxxx Xxxxx X. Xxxxxx Name: Xxxxxxx Xxxxxxx Xxxxx Title: Chief Financial Officer VP Treasurer Title: Senior Vice PresidentSVP

COUNTERSIGNATURE. This Amendment shall become effective only when it shall have been executed by Seller and Buyer. This Amendment is executed as a sealed instrument under the laws of the Commonwealth of Massachusetts as of the date first written above. SELLER: BUYER: ASPEN TECHNOLOGY, INC. SILICON VALLEY BANK By: /s/ Xxxxxxx X. Xxxxxx Xxxx By: /s/ Xxxxxxx Xxxxxxx Name: Xxxxxxx X. Xxxxxx Name: Xxxxxxx Xxxxxxx Title: Chief Financial Officer Title: Senior Vice PresidentXxxx Xxxx ----------------------------- -----------------------

COUNTERSIGNATURE. This Amendment shall become effective only when it shall have been executed by Seller and Buyer. This Amendment is executed as a sealed instrument under the laws of the Commonwealth of Massachusetts as of the date first written above. SELLER: BUYER: ASPEN TECHNOLOGY, INC. SILICON VALLEY BANK By: /s/ Xxxxxxx X. Xxxxxx By: /s/ Xxxxxxx Xxxxxxx Name: Xxxxxxx X. Xxxxxx Name: Xxxxxxx Xxxxxxx Title: Chief Financial Officer CFO Title: Senior Vice PresidentSVP

COUNTERSIGNATURE. This Amendment shall become effective only when it shall have been executed by Seller and Buyer. This Amendment is executed as a sealed instrument under the laws of the Commonwealth of Massachusetts as of the date first written above. SELLER: BUYER: ASPEN TECHNOLOGY, INC. SILICON VALLEY BANK By: /s/ Xxx X. Xxxxxxx X. Xxxxxx By: /s/ Xxxxxxx Xxxxxxx Name: Xxx X. Xxxxxxx X. Xxxxxx Name: Xxxxxxx Xxxxxxx Title: Chief Financial Officer Treasurer Title: Senior Vice President

COUNTERSIGNATURE. This Amendment shall become effective only when it shall have been executed by Seller and Buyer. This Amendment is executed as a sealed instrument under the laws of the Commonwealth of Massachusetts as of the date first written above. SELLER: BUYER: ASPEN TECHNOLOGY, INC. SILICON VALLEY BANK By: /s/ Xxx X. Xxxxxxx X. Xxxxxx By: /s/ Xxxxxxx Name: Xxx Xxxxxxx Name: Xxxxxxx X. Xxxxxx Name: Xxxxxxx Xxxxxxx Title: Chief Financial Officer VP Treasurer Title: Senior Vice President:

COUNTERSIGNATURE. This Amendment shall become effective only when it shall have been executed by Seller and Buyer. This Amendment is executed as a sealed instrument under the laws of the Commonwealth of Massachusetts as of the date first written above. SELLER: BUYER: ASPEN TECHNOLOGY, INC. SILICON VALLEY BANK By: /s/ Xxxxxxx X. Xxxxx Xxxxxx By: /s/ Xxxxxxx Xxxxxxx Name: Xxxxxxx X. Xxxxx Xxxxxx Name: Xxxxxxx Xxxxxxx Title: Chief Financial Officer Treasurer Title: Senior Vice PresidentBy: /s/ Xxxx X. Xxxxxxxx Name: Xxxx X. Xxxxxxxx Title: CFO

COUNTERSIGNATURE. This Amendment shall become effective only when it shall have been executed by Seller and Buyer. [remainder of page is intentionally left blank] This Amendment is executed as a sealed instrument under the laws of the Commonwealth of Massachusetts as of the date first written above. SELLER: BUYER: ASPEN TECHNOLOGY, INC. SILICON VALLEY BANK By: /s/ Xxxxxxx Xxxx X. Xxxxxx Xxxxx By: /s/ Xxxxxxx Xxxxxxx Xxxx Xxxxxxxxxxx Name: Xxxxxxx Xxxx X. Xxxxxx Xxxxx Name: Xxxxxxx Xxxxxxx Xxxx Xxxxxxxxxxx Title: Chief Financial Officer President and CEO Title: Senior Vice President

COUNTERSIGNATURE. This Amendment shall become effective only when it shall have been executed by Seller and Buyer. This Amendment is executed as a sealed instrument under the laws of the Commonwealth of Massachusetts as of the date first written above. SELLERBORROWER: BUYERBANK: ASPEN TECHNOLOGY, INC. ARBINET CORPORATION SILICON VALLEY BANK By: /s/ Xxxxxxx X. Gxxx Xxxxxx By: /s/ Xxxxxxx Xxxxxxx Axxxx X. Xxxxxxxxxx Name: Xxxxxxx X. Gxxx Xxxxxx Name: Xxxxxxx Xxxxxxx Title: Chief Financial Officer Title: Senior Vice PresidentAxxxx X. Xxxxxxxxxx

COUNTERSIGNATURE. This Amendment shall become effective only when it shall have been executed by Seller and Buyer. This Amendment is executed as a sealed instrument under the laws of the Commonwealth of Massachusetts as of the date first written above. SELLER: BUYER: ASPEN TECHNOLOGY, INC. SILICON VALLEY BANK By: /s/ Xxxxxxx X. Xxxxxx By: /s/ Xxxxxxx Xxxxxxx Name: Xxxxxxx X. Xxxxxx Name: Xxxxxxx Xxxxxxx Title: Chief Financial Officer CFO Title: Senior Vice President

COUNTERSIGNATURE. This Amendment shall become effective only when it shall have been executed by Seller and Buyer. This Amendment is executed as a sealed instrument under the laws of the Commonwealth of Massachusetts as of the date first written above. SELLER: BUYER: ASPEN TECHNOLOGY, INC. SILICON VALLEY BANK By: /s/ Xxxxxxx X. Xxxxxx Xxx X.Xxxxxxx By: /s/ Xxxxxxx Xxxxxxx Xxxx X. Xxxx Name: Xxxxxxx X. Xxxxxx Xxx X.Xxxxxxx Name: Xxxxxxx Xxxxxxx Xxxx X. Xxxx Title: Chief Financial Officer VP- Treasurer Title: Senior Vice President

COUNTERSIGNATURE. This Amendment shall become effective only when it shall have been executed by Seller and Buyer. This Amendment is executed as a sealed instrument under the laws of the Commonwealth of Massachusetts as of the date first written above. SELLER: BUYER: ASPEN TECHNOLOGY, INC. SILICON VALLEY BANK By: /s/ Xxx X. Xxxxxxx X. Xxxxxx By: /s/ Xxxxxxx Xxxx Xxxxxxxxx Name: Xxx X. Xxxxxxx Name: Xxxxxxx X. Xxxxxx Name: Xxxxxxx Xxxxxxx Xxxx Xxxxxxxxx Title: Chief Financial Officer Treasurer Title: Senior Vice PresidentRelationship Manager