May 17, 2006

Via U.S. Mail

Alex Mashinsky
c/o Governing Dynamics Investments, LLC
510 Berkeley Square
Memphis, TN  38120

      Re: 	Arbinet-thexchange, Inc.
Response letter dated May 12, 2006 regarding Definitive Additional
Materials
Filed May 4, 2006 by Alex Mashinsky and Robert A. Marmon
      File No. 000-51063

Dear Mr. Mashinsky:

      We have reviewed your filing and have the following comment.
Where indicated, we think you should revise your document in
response
to this comment.  If you disagree, we will consider your
explanation
as to why our comment is inapplicable or a revision is
unnecessary.
Please be as detailed as necessary in your explanation.  In some
of
our comments, we may ask you to provide us with supplemental
information so we may better understand your disclosure.  After
reviewing this information, we may or may not raise additional
comments.

      Please understand that the purpose of our review process is
to
assist you in your compliance with the applicable disclosure
requirements and to enhance the overall disclosure in your filing.
We look forward to working with you in these respects.  We welcome
any questions you may have about our comments or any other aspect
of
our review.  Feel free to call us at the telephone numbers listed
at
the end of this letter.

Additional Definitive Materials

1. We note your response to our comment letter dated May 5, 2006.
Your support for the statement you make that "top management of
the
Company - Curt Hockemeier and Anthony Craig - just last week
received
over $3,600,000 in `extra` compensation by purchasing over 430,000
shares of stock (1.7% of the Company) for $.16 (sixteen cents!)
per
share..." goes to the numerical values you present here but it
does
go to the context in which you have presented this statement.
Specifically, you characterize the option grant as "extra"
compensation and "bonus" option consideration thereby implying
that
the individuals were just granted the shares when, in fact, the
exercise of the underlying option relates to a historical grant
and,
therefore, likely relates to past performance.  Without providing
this context, readers might be led to believe that the company
recently granted these options at a strike price significantly
under
the recent closing price of the common stock and that the company
had
something to do with the recent receipt of proceeds when the
exercise
of these options is not within the company`s control.  Please
revise
to remove this implication.

2. Provide additional support and context for the statement that
Mr.
Mashinsky is "just full of nutty ideas."  Your indication that it
was
said to Mr. Marmon by management is insufficient without providing
additional context.  Further, your indication that the inclusion
of
the statement was "intended to show the current CEO`s view of Mr.
Mashinsky" is not consistent with the context in which the
statement
was made, considering it is followed up by "[w]e are not aware of
any
technology patents written by Mr. Hockemeier."  Please revise.

      As appropriate, please respond to these comments within 10
business days or tell us when you will provide us with a response.
You may wish to provide us with marked copies of the amendment to
expedite our review.  Please furnish a cover letter with your
amendment that keys your responses to our comments and provides
any
requested supplemental information.  Detailed cover letters
greatly
facilitate our review.  Please understand that we may have
additional
comments after reviewing your amendment and responses to our
comments.

	You may contact me at (202) 551-3264 with any questions.  You
may also reach me via facsimile at (202) 772-9203.

			Sincerely,


			Mara L. Ransom
			Special Counsel
			Office of Mergers and
	Acquisitions

cc via facsimile at (212) 822-5735:

Roland Hlawaty, Esq.
Milbank, Tweed, Hadley & McCloy LLP
Arbinet-thexchange, Inc.
May 17, 2006
Page 1



UNITED STATES
SECURITIES AND EXCHANGE COMMISSION
WASHINGTON, D.C. 20549-3628

         DIVISION OF
CORPORATION FINANCE