SecProbe.io

January 3, 2014

Via E -mail
Mr. Brian Carolan
Chief Financial Officer
CommVault Systems, Inc.
2 Crescent Place
Oceanport, NJ 07757

Re: CommVault Systems, Inc.
 Form 10-K for the Fiscal Year Ended March 31, 201 3
Filed May 14, 2013
Form 10 -Q for the Quarter ly Period  Ended September 30, 2013
Filed October 31, 2013
File No. 001 -33026

Dear Mr. Carolan :

We have reviewed your filing s and have the following comment.  In our comment , we
may ask you to provide us with information so we may better understand your disclosure.

Please respond to this letter within ten business days by amending your filing, by
providing the requested information, or by advising us when you will pro vide the requested
response.   If you do not believe our comment applies to your facts and circumstances or do not
believe an amendment is appropriate, please tell us why in your response.

After reviewing any amendment to your filing and the information you provide in
response to this comment, we may have  additional comments.

Form 10 -Q for the Quarter ly Period Ended September 30, 2013

Management’s Discussion and Analysis of Financial Condition and Results of Operations

Sources of Revenue s, page 15
1. We note you r disclosure on page 16 that the worldwide reseller and original equipment
agreements with Dell accounted  for 20% of your total revenue for the six months ended
September 30, 2013.  You further disclose that on October 16, 2013 you notified Dell of
your intention to terminate the original equipment agreement as of December 16, 2013;
however , the reseller agre ement currently remains in place.  Please tell us the percentage
of revenue generated from  each of these  agreements with Dell for the six months ended
September 30, 2013 and the twelve months ended March 31, 2013.  Also, tell us what

Mr. Brian Carolan
CommVault Systems, Inc.
January 3, 2014
Page 2

 consideration was given to including such information in future filings in order to provide
investors with a better sense as to the impact of the terminated agreement on your results
of operations in the future.

We urge all persons who are responsible for the accuracy and ade quacy of the disclosure
in the filing to be certain that the filing includes the information the Securities Exchange Act of
1934 and all applicable Exchange Act rules require.   Since the company and its management are
in possession of all facts relating to  a company’s disclosure, they are responsible for the accuracy
and adequacy of the disclosures they have made.

 In responding to our comment, please provide  a written statement from the company
acknowledging that:

 the company is responsible for the ade quacy and accuracy of the disclosure in the filing;

 staff comments or changes to disclosure in response to staff comments do not foreclose
the Commission from taking any action with respect to the filing; and

 the company may not assert staff comments as a defense in any proceeding initiated by
the Commission or any person under the federal securities laws of the United States.

You may contact Melissa Kindelan, Staff Accountan t at (202) 551 -3564  or Christine
Davis , Assistant Chief Accountant, at (202) 551 -3408  if you have questions regarding comments
on the financial statements and re lated matters.  Please contact me at (202) 551 -3406  with any
other questions.

Sincerely,

 /s/ Patrick Gilmore

Patrick Gilmore
Accounting Branch Chi ef