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INSTITUTIONAL SHAREHOLDER SERVICES
June 8, 2006
Dear Fellow Stockholder:
As we approach the final days until the Arbinet annual meeting of stockholders, we are pleased to inform you that Institutional Shareholder Services (ISS) has recommended that shareholders vote “FOR” the election of Alex Mashinsky and Robert A. Marmon to Arbinet’s Board of Directors. ISS is the nation’s premier independent proxy advisory service and we are grateful that they agreed with our conviction that our representation on the Board would benefit both our Company and our fellow stockholders.
In its analysis, ISS recognized that, “The poor performance of the company and the dissidents’ backgrounds establish both the need for change and the dissidents’ ability to effect potential change.” ISS then concluded, “Given the dissidents’ previous role in the company, ISS believes that the election of the dissident slate may place the board in a better position to take steps to reinvigorate the company for further progress than the incumbent board.”
We, together with our group, have increased our holdings to over 7.5% of Arbinet’s outstanding common shares. Aligning ourselves squarely with Arbinet’s long suffering shareholders, we purchased 1.4% in additional sharesafter the record dateat market prices. On the other hand, Arbinet’s current leadership, Messrs. Hockemeier and Craig, saw fit to purchase 1.7% of the company justbeforethe record date atsixteen cents per share, knowingly diluting all other shareholders and gaining over 425,000 more shares to vote for their own failed strategy.Now we are asking you — the true owners of Arbinet — to demand a shareholder voice on the Board by voting the enclosed GREEN proxy card today.
We understand that you have probably received multiple mailings from both sides during this campaign and we would like to thank you for your patience. We would also like to thank those of you who have supported our campaign and urge all stockholders, no matter how few or how many shares you may own, to vote theGREENproxy card for a better future at Arbinet.
PLEASE LEND YOUR SUPPORT TO OUR CAMPAIGN
Please Mark, Sign and Return The Enclosed GREEN Proxy Card Today!
If you want to vote for Mashinsky and Marmon,
Donot sign any White Card!
If you have already signed a White Card, you mustresend the enclosed GREEN Card.
This Management and Board Need to Be Sent a Clear Message of
“NO CONFIDENCE”
By You — Arbinet’s Owners
If you have any questions, or need assistance in voting yourGREENproxy card, please call our proxy solicitor, MacKenzie Partners, Inc., Toll-Free at 800-322-2885
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| Alex Mashinsky | Robert A. Marmon |