SecProbe.io

July 30, 2010
 Mr. Mark S. Casady Chief Executive Officer and Chairman LPL Investment Holdings Inc. One Beacon Street
Boston, MA 02108

Re: LPL Investment Holdings Inc.
Amendment No. 2 to Registrati on Statement on Form S-1
Filed July 9, 2010
  File No. 333-167325

Dear Mr. Casady:

We have reviewed your registration statem ent and have the following comments.  In
some of our comments, we may ask you to provi de us with information so we may better
understand your disclosure.
 Please respond to this letter by amending your registration statement and providing the
requested information.  If you do not believe  our comments apply 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 re gistration statement and the information you
provide in response to these comments, we may have additional comments.
 General

 1. We have reviewed your response to comment 1 from our letter dated July 2, 2010 and the
back-up materials provided to us.  Please prov ide us with the original source material for
the following statement that appears on page  83: “In the 2010 ranki ngs of the Top 1,000
Financial Advisors in Barron’s survey, thirty-one of our advisors appear in the top 1,000
and three in the top 100.”
Management’s Discussion and Analysis of Financ ial Condition and Results of Operations, page 31

 Overview, page 31

 Adjusted Net Income and Adjusted Net Income per share, page 42

 2. We have reviewed your response to comm ent 25 from our letter dated July 2, 2010.
Please reconcile the EBITDA Adjustments lin e item in your rec onciliation (i.e. $46,089

Mr. Mark S. Casady Chief Executive Officer and Chairman LPL Investment Holdings Inc. July 30, 2010 Page 2

for the fiscal year ended December 31, 2009)  to the actual adjustments made to net
income to arrive at EBITDA presented earlier .  Within your response please make it clear
how the amortization component of purchas ed intangibles is treated within each
reconciliation.
 Quantitative and Qualitative Disclosu res About Market Risk, page 71

 Market Risk, page 71

 3. Please expand your disclosure to include a more  detailed description of the risk limits on
your trading inventory.  Als o, please explain who is res ponsible for establishing and
monitoring compliance with thes e risk limits, and whether you exceeded risk limits at any
time during the fiscal year.
 Principal and Selling Stockholders, page 120

 4. We note your response to comment 43 from our  letter dated July 2, 2010.  Please include
a specific reference in the selling stockholder table to the Form 8-K that will contain the
information regarding the “Other  Selling Stockholders.”  Plea se also disclose the number
of “Other Selling Stockholders” that w ill be included in the line item.
 Financial Statements

Report of Independent Registered Public Accounting Firm, page F-27

5. In an amended filing, please include the t yped signature of your independent auditor
within the report.

Reportable Segment, page F-38
 6. We note your response to comment 49 from our letter dated July 2, 2010 and your
conclusion that the Independent Advisor Serv ices operating segment and the Institution
Services operating segment have similar ec onomic characteristics.  Please provide us
with a more detailed analysis of the input s that you considered which enabled you to
reach the conclusion that these operating segm ents have similar economic characteristics
based upon the historical results of these segm ents.  In your response, please provide to
us the actual gross margin as a percentage  of net revenue resu lts for both of these
segments for the historical period you anal yzed in order to reach your conclusion.

We urge all persons who are responsible for th e accuracy and adequacy of the disclosure
in the filing to be certain that the filing incl udes the information the Securities Act of 1933 and
all applicable Securities Act rules require.  Since the company and its management are in

Mr. Mark S. Casady Chief Executive Officer and Chairman LPL Investment Holdings Inc. July 30, 2010 Page 3

possession of all facts relating to a company’s disc losure, they are responsible for the accuracy
and adequacy of the disclosures they have made.
Notwithstanding our comments, in the event you request acceleration of  the effective date
of the pending registration statement please pr ovide a written statement from the company
acknowledging that:
• should the Commission or the staff, acting purs uant to delegated authority, declare the
filing effective, it does not foreclose the Co mmission from taking any action with respect
to the filing;

• the action of the Commission or the staff, acting pursuant to delegated authority, in
declaring the filing effective, does not relieve the company from its full responsibility for
the adequacy and accuracy of the disclosure in the filing; and

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

Please refer to Rules 460 and 461 regarding re quests for acceleration.  We will consider a
written request for acceleration of  the effective date of the regi stration statement as confirmation
of the fact that those reques ting acceleration are aware of thei r respective responsibilities under
the Securities Act of 1933 and the Securities Excha nge Act of 1934 as they relate to the proposed
public offering of the securities specified in th e above registration stat ement.  Please allow
adequate time for us to review any amendment prior to the requested effective date of the
registration statement.
 You may contact Howard Ef ron, Staff Accountant, at (202) 551-3439 or Kevin Woody,
Branch Chief, at (202) 551-3629 if you have que stions regarding comments on the financial
statements and related matters.  Please contac t Kristina Aberg, Attorney-Advisor, at (202) 551-
3404 or me at (202) 551-3655 with any other questions.
Sincerely,

 Sonia Gupta Barros Special Counsel
 cc: Julie H. Jones, Esq.  Keith F. Higgins, Esq.