Exhibit 10.28

[Execution Copy]

As of June 9, 2008

Mr. Laurence A. Tosi

388 W. Broadway

Loft B

New York, New York 10012

Dear Laurence:

We are pleased to confirm the terms relating to your becoming a Senior Managing
Director (“SMD”) and Chief Financial Officer of Blackstone (as defined below) as
soon as possible, but no later than December 10, 2008 (your “Start Date”). This
letter agreement (this “SMD Agreement”) shall be effective as of the “as of”
date first set forth above (the “Effective Date”) and sets forth the terms of
your becoming an SMD with Blackstone (as defined below). “Blackstone” or
“Blackstone Entities” means The Blackstone Group L.P. and its current and future
affiliates; provided, that the terms “Blackstone” and “Blackstone Entities” do
not include any investment fund affiliated with a Blackstone Entity or any
portfolio company or underlying investment of any fund affiliated with a
Blackstone Entity. The limited liability company agreement, limited partnership
agreement or other governing agreement of any Blackstone Entity in which you
have a partnership, membership or other participation interest, in each case now
or hereafter in existence and as amended and/or restated, is herein called such
Blackstone Entity’s “Governing Agreement.” “Active Member” of a Blackstone
Entity means a person who is (i) an SMD and (ii) an active member or partner
(excluding a withdrawn, retaining withdrawn or deceased member or partner) of
such Blackstone Entity.

1. Title; Reporting; Key Responsibilities.

(a) You will be Chief Financial Officer and an SMD of Blackstone.

(b) You will report to Hamilton E. James (“HEJ”), President and Chief Operating
Officer of the firm, and, if HEJ is not available, to Stephen A. Schwarzman
(“SAS”), Chairman and Chief Executive Officer of the firm.

(c) You will (i) serve on the Executive Committee of Blackstone, (ii) attend
meetings of the Management Committee and (iii) have such other duties as are
customary for the chief financial officer of a public company.

2. Your Annual Draw; Health and Related Benefits, Guaranteed Compensation.

(a) Except as otherwise provided herein, you will be paid such distributions and
benefits as may be determined by Blackstone from time to time. Effective as of
your Start Date, you will be entitled to take a draw at an annual rate equal to
the annual draw of other SMDs generally (which rate currently is $350,000
(prorated for any portion of a calendar year in which you are not an SMD)),
payable in equal monthly installments against your allocable share of the net
pre-tax income of certain Blackstone Entities and/or your annual bonus
compensation (including the 2008 Minimum Comp (defined below) for purposes of
the 2008 calendar year). You understand and agree that (x) the amounts and types
of your distributions remain at all times subject to the sole discretion of
Blackstone and are subject to change at any time and (y) Blackstone may alter,
amend, modify, discontinue or supplement any and all benefits, policies and
programs at any time in its sole discretion, except in each case for 2008
Minimum Comp as provided in Section 2(d) below and your percentage of net
management fee income and carried interest

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for 2009 as provided in Section 2(e) below. Your annual bonus may be subject to
Blackstone’s policies regarding minimum deferral on a basis generally consistent
with other SMDs; provided that you shall not be required by Blackstone to defer
any portion of the 2008 Minimum Comp.

(b) You will also receive health care insurance and other benefits related to
such health care insurance comparable to those provided generally to all SMDs.
You hereby acknowledge that, as an SMD, you will be responsible for the payment
of such insurance and other benefits on the same basis generally as other SMDs.
You will also receive all other benefits generally available to other SMDs,
including five weeks of annual vacation (prorated for any calendar year in which
you are an SMD for less than the entire calendar year).

(c) During your service at Blackstone (in any capacity) and until the expiration
of all transfer restrictions applicable to any limited partner interests or
units you may hold of Blackstone Holdings or The Blackstone Group L.P.,
respectively (collectively, the “BX Units”), you agree (on behalf of yourself
and any and all estate planning vehicles, partnerships or other legal entities
controlled by or affiliated with you (“Affiliated Vehicles”)) that all BX Units
held by you and all such Affiliated Vehicles will only be held in an account at
Blackstone’s equity plan administrator or otherwise administered by such
administrator.

(d) If (i) you are still an SMD with Blackstone on December 31, 2008,
(ii) Blackstone terminates your services as an SMD without Cause (as defined
below, except that for purposes of this Section 2(d), Section 3(c)(ii) and
Section 3(c)(iii), all determinations of Cause shall be made using an objective,
reasonable person standard) prior to December 31, 2008 or (iii) Blackstone
breaches its agreement to commence your service on the terms specified in
Section 1 on or about your Start Date, you will be entitled to guaranteed
minimum aggregate compensation of $3,500,000 cash for 2008 (“2008 Minimum
Comp”), which amount includes the pro rated amount of your annual draw as set
forth in Section 2(a) for services performed in 2008 and your annual bonus
(including any portion of such amounts that you may, at your sole discretion,
elect to defer). If your service as an SMD is terminated by Blackstone without
Cause prior to December 31, 2008 or Blackstone breaches its agreement to
commence your service on the terms specified in Section 1 on or about the Start
Date, your 2008 Minimum Comp shall be paid to you within 30 days of such
termination or the elapsed Start Date, as applicable.

(e) If you are still an SMD with Blackstone on December 31, 2009, you will be
entitled to (i) 0.215% of the net management fee income (before SMD compensation
and taxes except New York City unincorporated business tax) from Blackstone
Entities that generate (non-performance/non-incentive) management fees from
investment funds and portfolio companies affiliated with any Blackstone Entities
and (ii) 0.2% of the profit sharing percentage in all Blackstone carried
interest vehicle transactions that close after January 1, 2009, subject to
applicable vesting. Carried interest with respect to any transaction will be
subject to customary obligations and conditions contained in the Governing
Agreements of the Blackstone Entity (e.g., vesting, clawback, holdback, capital
commitment obligations, forfeitures, future dilution) on the same terms
applicable to other SMDs generally working on such transaction.

3. Side-by-Side Investment; Funds of Funds; Deferred Units.

(a) Side-by-Side Allocations. You will also be allocated $1,250,000 for each
election period (or approximately $2,500,000 per year at a normalized investment
rate) (subject to proration for any portion of an annual election period in
which you are not an SMD) in side-by-side investment opportunities generated
through BCP V, BREP VI, BREP International II and Blackstone Mezzanine Partners
II L.P. (and/or other side-by-side investment opportunities that become
available to SMDs generally), such aggregate amount to be allocated among the
foregoing funds for each annual

 

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election period in proportion, as nearly as practicable, to the amounts of
side-by-side investment opportunities available through the respective funds for
such annual election period; provided that (i) your allocations will provide you
the opportunity, but not the obligation, to invest personally and (ii) your
allocations in 2008 shall be made available only if you can demonstrate to
Blackstone that you are a “qualified purchaser” under the Securities Act of
1933, as amended.

(b) Funds of Funds. You will have the opportunity, but not the obligation, to
invest personally in Blackstone’s fund of funds investment products managed by
Blackstone Alternative Asset Management L.P. (or its successor, “BAAM”) as long
as you serve as an SMD, subject to the same limitations on exclusions from
management fees or incentive fees that are applicable to other SMDs generally
with respect to their BAAM investments; provided that you invest an amount in
such fund of funds investment products that is reasonably consistent with
amounts invested therein generally by other SMDs, as determined by Blackstone.

(c) Deferred Unit Awards

(i) Start Date Awards. You will receive promptly after the Start Date, two
equity-based awards (the “Start Date Awards”) under Section 8 of the Blackstone
Group L.P. 2007 Equity Incentive Plan (the “Plan”) equal, respectively, to:

 

  1. 155,764 deferred partnership units (“Partnership Units”) of Blackstone
Holdings (as defined in the IPO registration statement of The Blackstone Group
L.P.) (“Deferred Units”) (the “Sign-On Grant”); and

 

  2. 338,381 Deferred Units (the “Make-Whole Grant”), representing the
forfeiture of compensation-related items from Merrill Lynch (the “Forfeited
Equity”).

(ii) 2008 Equity Bonus Award. In addition to the Start Date Awards, if (A) you
are still an SMD with Blackstone on the date in calendar year 2009 when bonuses
generally are paid to other SMDs in respect of calendar year 2008 (e.g., around
January 15, 2009), (B) Blackstone terminates your services as an SMD without
Cause prior to such payment date or (C) Blackstone breaches its agreement to
commence your service on the terms specified in Section 1 on or about your Start
Date, then you will receive an equity-based award under Section 8 of the Plan
equal to $4,500,000 of Deferred Units, calculated using the 30-day volume
weighted average trading price of Partnership Units prior to the date of grant
(the “2008 Equity Bonus Grant” and, together with the Start Date Awards, the
“Awards”).

(iii) Vesting. The Deferred Units will vest as follows:

 

  1. The Deferred Units underlying the Sign-On Grant will vest 100% on the fifth
anniversary of the Start Date (with no partial period vesting);

 

  2. The Deferred Units underlying the Make-Whole Grant will vest and any
restrictions shall lapse in accordance with the vesting schedule of the
Forfeited Equity (as set forth on Schedule A); and

 

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  3. The Deferred Units underlying the 2008 Equity Bonus Grant will vest such
that 20% vest upon each of the first, second, third, fourth and fifth
anniversaries of the grant date; provided that if the 2008 Equity Bonus Grant is
granted on the date set forth in clause (B) or clause (C) of paragraph
(ii) above, then the Deferred Units underlying the 2008 Equity Bonus Grant shall
be 100% vested on the applicable date of grant.

The unvested portion of your Awards will be terminated and will be null and void
(and cease to represent a right to receive Partnership Units) once you are no
longer an SMD of Blackstone for any reason, except that the then-outstanding,
but unvested portion of your Awards will become fully vested (and not subject to
call rights or repurchase rights, except as described in Section 3(c)(v) below
or in the Non-Competition Agreement) if (i) your service with Blackstone is
terminated by Blackstone without Cause or as a result of your death, permanent
disability or (ii) there is a Change in Control (as defined in the partnership
agreements of Blackstone Holdings). The unvested portion of your Award (and any
vested Deferred Units which have been retained and not yet delivered to you
pursuant to Section 3(c)(iv) below) will also be terminated and be null and void
upon the termination of your service with Blackstone for Cause.

(iv) Delivery of Partnership Units. As of each vesting date with respect to your
Awards, the number of Partnership Units corresponding to the vested portion of
the respective Awards shall be delivered to you; provided, however, that any
such Partnership Units that would otherwise be subject to continuing transfer
and forfeiture restrictions as described in Section 3(c)(v) shall not be
delivered to you as of the relevant vesting date and shall instead be retained
by Blackstone and delivered to you as of the date on which the related transfer
restrictions lapse and, in the event your services as an SMD are terminated,
forfeiture restrictions lapse. Prior to the delivery of the underlying
Partnership Units, you will not be the actual owner of the Partnership Units
underlying your Awards and will not have any voting rights or rights with
respect to distributions with respect to such Partnership Units, except as
provided in Section 3(c)(vi) below.

(v) Post-Vesting Transferability and Forfeiture Restrictions. The Partnership
Units delivered to you under any vested portion of your Deferred Units will
generally be freely transferable after vesting (subject to the partnership
agreements of Blackstone Holdings and any trading procedures established by
Blackstone and generally applicable to SMDs), except that (i) you may only
transfer up to 33 1/3%, 66 2/3% and 75% of the aggregate number of Deferred
Units which vested under each Award on and after the first, second and third
anniversaries, respectively, of your Start Date and (ii) you will not be
permitted to transfer more than 75% of the aggregate number of Deferred Units
which vested under your Awards during your service with Blackstone and,
following your termination of service, during the non-compete and non-solicit
periods described in the Non-Competition Agreement. The Partnership Units
underlying your Awards which are unvested or which are not transferable and thus
remain undelivered pursuant to Section 3(c)(iv), will also remain subject to the
forfeiture terms described under Section 3(c)(v) hereof and Section IV of the
Non-Competition Agreement until such restrictions lapse. All transfer
restrictions will lapse upon (i) your death or permanent disability or (ii) a
Change in Control.

 

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(vi) Dividends. To the extent that distributions or dividends are made with
respect to Partnership Units underlying your Deferred Units (i.e., those
Partnership Units that have not yet been delivered to you), you will receive
such distributions or dividends with respect to those Deferred Units (whether or
not vested and/or delivered) related to Blackstone earnings accruing during the
periods you are associated with Blackstone; provided that you will not be
entitled to dividends if you do not hold your vested units on any record date
(due to for example, your selling such units prior to a record date).

4. Compliance Policies; Non-Competition.

(a) You acknowledge and agree that you are subject to all applicable provisions
of the Blackstone compliance policies applicable to you that have been made
available to you, including the Compliance Policies and Procedures Manual (to
the extent applicable to you), Investment Adviser Compliance Policies and
Procedures and its related supplements (each, to the extent applicable to you),
and USA Patriot Act Anti-Money Laundering Policies, as well as Blackstone’s Code
of Business Conduct and Ethics (including the Code of Ethics for Financial
Professionals, if applicable) and the Employee Handbook and Business Continuity
Plan (or in the case of UK-based SMDs, the U.K. AML Manual and U.K. Compliance
Manual) (collectively, the “Blackstone Compliance Policies”).

(b) You acknowledge that you have executed the SMD Non-Competition and
Non-Solicitation Agreement, attached hereto as Schedule B (the “Non-Competition
Agreement”), and agree that the terms thereof are incorporated herein by
reference.

(c) Subject to Section 5.5 of the Agreement of Limited Partnership of The
Blackstone Group L.P., you acknowledge and agree that becoming a party to this
SMD Agreement does not afford you any rights with respect to the management
and/or operation of Blackstone.

5. Termination; Resignation

(a) You acknowledge and agree that Blackstone may terminate your service at any
time for any reason, or for no reason at all with or without Cause; provided,
however, that Blackstone shall provide you with written notice at least ninety
days prior to the date of the termination of your service during which
Blackstone may elect to place you on paid leave for all or part of such
ninety-day period; provided, further, that during such ninety-day period, you
shall continue to receive your base draw and benefits, subject to applicable law
and the payment of benefits-related premiums, but shall not receive or
participate in any profit sharing or bonus arrangements (including participation
in any carried interest or fee-sharing program).

(b) Notwithstanding the foregoing, you acknowledge and agree that Blackstone may
terminate your services hereunder for Cause and such termination shall be
effective immediately. For purposes of this SMD Agreement, Cause means the
occurrence or existence of any of the following as determined fairly,
reasonably, on an informed basis and in good faith by Blackstone: (i) (w) any
breach by you of any provision of the Non-Competition Agreement, (x) any
material breach of any rules or regulations of Blackstone applicable to you,
(y) your deliberate failure to perform your duties to Blackstone, or (z) your
committing to or engaging in any conduct or behavior that is or may be harmful
to Blackstone in a material way; provided that, in the case of any of the
foregoing clauses (w), (x), (y) and (z), Blackstone has given you written notice
(a “Notice of Breach”) within fifteen days after Blackstone becomes aware of
such action and you fail to cure such breach, failure to perform or conduct or
behavior within fifteen days after receipt by you of such Notice of Breach from
Blackstone (or such longer period, not to exceed an additional fifteen days, as
shall be reasonably required for such cure, provided that you are diligently
pursuing such cure); (ii) any act of fraud, misappropriation, dishonesty,
embezzlement or

 

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similar conduct against Blackstone; or (iii) conviction (on the basis of a trial
or by an accepted plea of guilty or nolo contendere) of a felony or crime
(including any misdemeanor charge involving moral turpitude, false statements or
misleading omissions, forgery, wrongful taking, embezzlement, extortion or
bribery), or a determination by a court of competent jurisdiction, by a
regulatory body or by a self-regulatory body having authority with respect to
securities laws, rules or regulations of the applicable securities industry,
that you individually have violated any applicable securities laws or any rules
or regulations thereunder, or any rules of any such self-regulatory body
(including, without limitation, any licensing requirement), if such conviction
or determination has a material adverse effect on (A) your ability to function
as an SMD, taking into account the services required of you and the nature of
Blackstone’s business or (B) the business of Blackstone.

(c) You agree to provide Blackstone with written notice of your intention to
terminate your service with Blackstone at least ninety days prior to the date of
such termination (the “Notice Period”). Written notice pursuant to this
Section 5(c) shall be provided to any of the Chief Executive Officer, Chief
Operating Officer or Chief Legal Officer of Blackstone. During the Notice
Period, you shall perform any and all duties as directed by Blackstone, in its
sole discretion.

(d) You shall be placed on garden leave status for a period commencing on the
day following the conclusion of the ninety-day Notice Period and continuing for
ninety days thereafter (the “Garden Leave Period”). During the Garden Leave
Period, you shall continue to receive your base draw and benefits, subject to
the payment of related premiums, but shall not receive or participate in any
profit sharing or bonus arrangements (including participation in any carried
interest or fee-sharing program). During the Garden Leave Period, you shall not
be required to carry out any duties for or on behalf of Blackstone. You agree
that you will not enter into any employment or other business relationship with
any other employer or otherwise prior to the conclusion of the Garden Leave
Period.

(e) The provisions of Sections 5(c) and 5(d) shall not be applicable in
instances in which your service with Blackstone is terminated by Blackstone with
or without Cause (including if Blackstone elects to terminate your service
during the Garden Leave Period).

6. Representations, Warranties and Covenants.

(a) Except as set forth on Schedule 6(a) and except for the agreements,
arrangements and plans listed on Schedule 6(a) hereto (true, correct and
complete copies of which have been delivered to Blackstone prior to the date
hereof), you represent and warrant, as of the date hereof and (except as would
not materially impair your ability to perform your duties as described herein)
as of your Start Date, as follows:

(i) This SMD Agreement and the Non-Competition Agreement (this SMD Agreement and
the Non-Competition Agreement being herein collectively called the “Other
Business Agreements”), constitute valid and binding obligations of you and your
affiliates, enforceable against you or any of your affiliates in accordance with
the terms thereof.

(ii) You are not subject to:

1. any restrictive covenants, including without limitation, relating to
competition, solicitation or confidentiality (other than general obligations to
maintain confidentiality consistent with your fiduciary and other executive
duties), arising from any agreement, oral, written or otherwise, between you and
any Other Person (as defined below); or

 

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2. any agreement, oral, written or otherwise, between you and any Other Person,
or any common law, statutory or fiduciary duty owed to any Other Person, that
will in any way (I) materially compromise, limit or restrict your ability to
perform your duties commencing on your Start Date on behalf of all Blackstone
Entities pursuant to any Other Business Agreement, (II) purport to bind
contractually or otherwise any of the Blackstone Entities, or (III) subject any
Blackstone Entity (or any partner, member, affiliate, officer or employee of any
of the foregoing) to any liability of any kind or to any claim by any Other
Person.

“Other Person” means any corporation, partnership, limited liability company,
sole proprietorship or other person, entity or association (other than a
Blackstone Entity), including, without limitation, any Employer-affiliated
Entity (as hereinafter defined). “Past or Present Employer” means any
corporation, partnership, limited liability company, sole proprietorship or
other person, entity or association with which you have or have had any
employment, partnership, limited liability company, consulting or similar
business relationship or of which you are or have been an officer or director.
“Employer-affiliated Entity” means, collectively, any Past or Present Employer
and any corporation, partnership, limited liability company, sole proprietorship
or other person, entity or association that is an affiliate, subsidiary,
predecessor or successor of any Past or Present Employer.

(iii) None of (A) the execution, delivery and performance of any of the Other
Business Agreements, (B) the consummation of the transactions contemplated
hereby or thereby or (C) compliance by you with any of the provisions hereof or
thereof will (x) (I) violate or conflict with, or result in a breach of, or
default under, any of the provisions of any contract, agreement or other
instrument or obligation (including, without limitation, any common law,
statutory or fiduciary duty) to which you are a party, or by which you or any of
your properties or assets may be bound or affected (including, without
limitation, any agreement with, or any common law, statutory or fiduciary duty
owed to, any Employer-affiliated Entity), or (II) subject any Blackstone Entity
(or any partner, member, affiliate, officer or employee of any of the forgoing)
to any liability of any kind or to any claim by any Other Person; (y) result in
a violation of any law, statute, rule, regulation, order, writ, injunction or
decree applicable to you or to your properties or assets; or (z) require any
consent or approval by, or any notification of, or filing with, any person
(including any Employer-affiliated Entity, governmental body or self-regulatory
organization).

(iv) There are no actions, suits, governmental investigations, claims or other
legal proceedings pending or, to your knowledge, threatened against you.

(v) You have not, directly or indirectly, solicited any partners, members,
executives, officers or employees of any Other Person (including, without
limitation, any Employer-affiliated Entity) for any employment, partnership,
limited liability company, consulting or similar business relationship with
Blackstone or any other entity.

(vi) You have all of the proper and necessary licenses (regulatory or otherwise)
to conduct your business activities contemplated by this SMD Agreement.

(vii) You have not violated, in any manner that might affect Blackstone, any of
the applicable provisions of any Employer-affiliated Entity’s employment
agreements, employee handbooks, benefit plans and similar instruments to which
you are or were subject prohibiting competition with such Employer-affiliated
Entity, solicitation of its clients or solicitation and/or hiring of its
employees (collectively referred to herein as “Employer-affiliated Entity
Restrictive Provisions”).

 

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(b) You covenant and agree that you will at all times (i) perform your
obligations under the Other Business Agreements in a manner (A) consistent with:
(I) your obligations under all other agreements to which you are a party, or by
which you or any of your properties or assets may be bound or affected
(including, without limitation, any agreement with any Employer-affiliated
Entity), and (II) any other legal obligations or duties to any Other Person
(including without limitation, any common law, statutory or fiduciary duties
owed to any Other Person), (ii) act in good faith in a manner that you
reasonably believe to be in Blackstone’s best interests; and (iii) remain in
full compliance with all Employer-affiliated Entity Restrictive Provisions to
which you are subject.

(c) Blackstone represents and warrants that the Other Business Agreements
constitute valid and binding obligations of Blackstone and its affiliates,
enforceable against Blackstone or its affiliates in accordance with the terms
thereof.

7. Arbitration; Venue. Any dispute, controversy or claim between you and
Blackstone, arising out of or concerning the provisions of this SMD Agreement,
your service with Blackstone or otherwise concerning any rights, obligations or
other aspects of your relationship with Blackstone, shall be finally resolved in
accordance with the provisions of Section VII of the Non-Competition Agreement.
Without limiting the foregoing, you acknowledge that a violation on your part of
this SMD Agreement would cause irreparable damage to Blackstone. Accordingly,
you agree that Blackstone will be entitled to injunctive relief for any actual
or threatened violation of this SMD Agreement in addition to any other remedies
it may have.

8. Successors and Assigns. This SMD Agreement shall be binding upon and inure to
the benefit of the parties hereto and their respective predecessors, successors,
assigns, heirs, executors, administrators and personal representatives, and each
of them, whether so expressed or not, and to the extent provided herein, the
affiliates of the parties and Blackstone. This SMD Agreement is not assignable
by you without the prior written consent of Blackstone, and any attempted
assignment of this SMD Agreement, without such prior written consent, shall be
void.

9. Entire Agreement. This SMD Agreement (including the schedule hereto, which is
incorporated herein by reference and made a part hereof), embodies the complete
agreement and understanding among the parties with respect to the subject matter
hereof and thereof and supersedes and terminates any prior understandings,
agreements or representations, written or oral, which may have related to the
subject matter hereof or thereof in any way, except, to the extent you become a
party thereto after the date hereof, for any (i) governing agreements of the
general partners or managing members (collectively, “General Partners”) of
Blackstone sponsored investment funds; and (ii) any guarantees executed by you
for the benefit of any limited partners or General Partners of any Blackstone
sponsored investment fund in respect of any “clawback” obligation to such
Blackstone sponsored investment fund. For the sake of clarity, to the extent of
any conflict between Sections 2 and 3 of this SMD Agreement, on the one hand,
and the Plan or any Governing Agreement, on the other hand, the provisions of
Sections 2 and 3 of this SMD Agreement shall govern.

10. No Implied Duty. Except as otherwise expressly provided in this SMD
Agreement, neither the Blackstone Entities nor any of their members, partners or
affiliates will be under any duty, express or implied, of any kind or nature
whatsoever (including, without limitation, any implied duty of good faith and
fair dealing) to have revenues, earnings, income or carried interest
distributions of any particular amount or at any particular level such that you
will be entitled to compensation, earnings, income or distributions of any
particular amount, to cause any amount to be available for distribution to any
person, or to distribute any amount to any person, or to maintain your profit
sharing percentage at, or raise your profit sharing percentage to, any level, or
to retain you as a member or partner of any Blackstone Entity for any period of
time or through any particular date that may be necessary to entitle you to
receive any amount.

 

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11. Legal Fees. Blackstone will reimburse you for your legal fees and expenses
related to the negotiation and execution of this SMD Agreement; provided that
such reimbursement shall not exceed $15,000.

12. Indemnification. You will be entitled to the indemnification provisions on
the terms provided in the partnership agreements of Blackstone Holdings (in the
form that they exist at the relevant time of such indemnification with respect
to the senior executive officers of Blackstone), during and following the
termination of your service with Blackstone, and your rights under this
Section 12 and partnership agreements of Blackstone Holdings shall survive
indefinitely regardless of termination of this SMD Agreement for any reason.

13. Headings. The section headings in this SMD Agreement are for convenience of
reference only and shall in no event affect the meaning or interpretation of
this SMD Agreement.

14. Modification or Waiver in Writing. This SMD Agreement may not be modified or
amended except by a writing signed by each of the parties hereto. No waiver of
this SMD Agreement or of any promises, obligations or conditions contained
herein shall be valid unless in writing and signed by the party against whom
such waiver is to be enforced. No delay on the part of any person in exercising
any right, remedy or power hereunder shall operate as a waiver thereof, nor
shall any waiver on the part of any person of any such right, remedy or power,
nor any single or partial exercise of any such right, remedy or power, preclude
any further exercise thereof or the exercise of any other right, remedy or
power.

15. Blackstone Partnership Agreement. This SMD Agreement shall be treated as
part of the partnership agreements of Blackstone Holdings for purposes of
Section 761(c) of the Code and Sections 1.704-1(b)(2)(ii)(h) and 1.761-1(c) of
the Treasury Regulations. Unless otherwise determined by Blackstone, the amounts
payable hereunder shall be paid to you in your capacity as a member or partner
of one or more applicable Blackstone Entities and shall be appropriately
reflected on your IRS Schedule(s) K-1. The parties do not intend to create an
employer-employee relationship hereby and no amounts payable hereunder shall be
treated as compensation paid to an employee for tax purposes. You covenant and
agree that you will pay all U.S. federal, state, local and foreign taxes on the
amounts payable hereunder that are required by law to be paid by you.

16. Governing Law. This SMD Agreement shall be governed by and construed in
accordance with the laws of the State of New York applicable to agreements made
and to be performed entirely within such State.

17. Counterparts. This SMD Agreement may be executed in any number of
counterparts, each of which shall be an original and all of which shall
constitute one and the same instrument. Signatures delivered by facsimile shall
be effective for all purposes.

18. Conditions. This SMD Agreement shall not be effective until the completion
of a satisfactory drug screening and background check (with respect to
education, criminal, employment and credit records). You hereby acknowledge and
accept Blackstone’s employee policies and procedures.

 

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WHEREOF, the parties hereto have duly executed this Senior Managing Director
Agreement as of the date first above written,

 

BLACKSTONE HOLDINGS I L.P. By:   Blackstone Holdings I/II GP Inc., its general
partner By:  

/s/ Stephen A. Schwarzman

Name:   Stephen A. Schwarzman Title:   Chairman and Chief Executive Officer

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By:  

/s/ Laurence A. Tosi

  (Please sign above) Print Name:    Laurence A. Tosi

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SMD Non-Competition and Non-Solicitation Agreement

This SMD Non-Competition and Non-Solicitation Agreement, dated as of June 9,
2008 (the “Non-Competition Agreement”), between Blackstone Holdings I L.P., a
Delaware limited partnership, Blackstone Holdings II L.P., a Delaware limited
partnership, Blackstone Holdings III L.P., a Delaware limited partnership,
Blackstone Holdings IV L.P., a Québec société en commandite, and Blackstone
Holdings V L.P., a Québec société en commandite (collectively, “Blackstone
Holdings” and, together with its subsidiaries and affiliated entities,
“Blackstone”), and each of the other persons from time to time party hereto
(each, an “SMD”).

WHEREAS,

(a) Each SMD acknowledges and agrees that it is essential to the success of
Blackstone that Blackstone be protected by non-competition and non-solicitation
agreements that will be entered into by such SMD and other SMDs of Blackstone;

(b) Each SMD acknowledges and agrees that Blackstone would suffer significant
and irreparable harm from SMD competing with Blackstone after the termination of
SMD’s service with Blackstone; and

(c) Each SMD acknowledges and agrees that in the course of such SMD’s service
with Blackstone, such SMD has been and will be provided with Confidential
Information (as hereinafter defined) of Blackstone, and has been and will be
provided with the opportunity to develop relationships with investors and
clients, prospective investors and clients, employees and other agents of
Blackstone, and such SMD further acknowledges that such Confidential Information
and relationships are extremely valuable assets in which Blackstone has invested
and will continue to invest substantial time, effort and expense;

NOW, THEREFORE, for good and valuable consideration, each SMD and Blackstone
hereby covenant and agree to the following restrictions which such SMD
acknowledges and agrees are reasonable and necessary to protect the legitimate
business interests of Blackstone and which will not unnecessarily or
unreasonably restrict such SMD’s professional opportunities should his or her
service with Blackstone terminate:

I. Non-Competition and Non-Solicitation Covenants

A. Non-Competition. Each SMD shall not, directly or indirectly, during such
SMD’s service with Blackstone, and for a period ending twelve months following
(i) the termination by Blackstone of such SMD’s service pursuant to Sections
5(a) or 5(b) of the SMD Agreement, or (ii) the commencement of such SMD’s Garden
Leave Period pursuant to Section 5(d) of the SMD Agreement, associate (including
but not limited to association as a sole proprietor, owner, employer, principal,
investor, joint venturer, shareholder, associate, employee, member, consultant,
contractor or otherwise) with any Competitive Business or any of the affiliates,
related entities, successors or assigns of any Competitive Business; provided
however that with respect to the equity of any Competitive Business which is or
becomes publicly traded, such SMD’s ownership as a passive investor of less than
3% of the outstanding publicly traded stock of a Competitive Business shall not
be deemed a violation of this Non-Competition Agreement; provided further that
if such SMD’s service with Blackstone is terminated without Cause by Blackstone,
then the foregoing period of time will be reduced to 90 days rather than twelve
months. For purposes of this Non-Competition Agreement, “Competitive Business”
means any business, in any geographical or market area where Blackstone conducts
business or provides products or services, that competes with the business of
Blackstone, including any business in which Blackstone

 

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engaged during the term of such SMD’s service and any business that Blackstone
was actively considering conducting at the time of such SMD’s termination of
service and of which such SMD has, or reasonably should have, knowledge.

B. Non-Solicitation of Clients/Investors. Each SMD shall not, directly or
indirectly, during such SMD’s service with Blackstone, and for a period ending
twelve months following (i) the termination by Blackstone of such SMD’s service
pursuant to Sections 5(a) or 5(b) of the SMD Agreement, or (ii) the commencement
of such SMD’s Garden Leave Period pursuant to Section 5(d) of the SMD Agreement,
(a) solicit, or assist any other individual, person, firm or other entity in
soliciting, the business of any Client or Prospective Client for or on behalf of
an existing or prospective Competitive Business; (b) perform, provide or assist
any other individual, person, firm or other entity in performing or providing,
services similar to those provided by Blackstone, for any Client or Prospective
Client; or (c) impede or otherwise interfere with or damage (or attempt to
impede or otherwise interfere with or damage) any business relationship and/or
agreement between Blackstone and (i) a Client or Prospective Client or (ii) any
supplier.

1. For purposes of this Non-Competition Agreement, “Client” shall mean any
person, firm, corporation or other organization whatsoever for whom Blackstone
provided services (including without limitation any investor in any Blackstone
fund, any portfolio company of a Blackstone fund, any client of any Blackstone
business group or any other person for whom Blackstone renders any service) with
respect to whom each SMD, individuals reporting to such SMD or individuals over
whom such SMD had direct or indirect responsibility, had personal contact or
dealings on Blackstone’s behalf during the three-year period immediately
preceding such SMD’s termination of service. “Prospective Client” shall mean any
person, firm, corporation or other organization whatsoever with whom Blackstone
has had any negotiations or discussions regarding the possible engagement of
business, investment in a Blackstone fund, investment in or provision of
services to any portfolio company of a Blackstone fund, or the performance of
business services within the eighteen months preceding such SMD’s termination of
service with Blackstone with respect to whom such SMD, individuals reporting to
such SMD or individuals over whom such SMD had direct or indirect
responsibility, had personal contact or dealing on Blackstone’s behalf during
such eighteen-month period.

2. For purposes of this Section I.B., “solicit” means to have any direct or
indirect communication of any kind whatsoever, regardless of by whom initiated,
inviting, advising, encouraging or requesting any individual, person, firm or
other entity, in any manner, to take or refrain from taking any action.

C. Non-Solicitation of Employees/Consultants. Each SMD shall not, directly or
indirectly, during such SMD’s service with Blackstone, and for a period ending
two years following (i) the termination by Blackstone of such SMD’s service
pursuant to Sections 5(a) or 5(b) of the SMD Agreement or (ii) the commencement
of such SMD’s Garden Leave Period pursuant to Section 5(d) of the SMD Agreement
(such period, the “Restricted Period”), solicit, employ, engage or retain, or
assist any other individual, person, firm or other entity in soliciting,
employing, engaging or retaining, (a) any employee or other agent of Blackstone,
including without limitation any former employee or other agent of Blackstone
who ceased working for Blackstone within the twelve-month period immediately
preceding or following the date on which such SMD’s service with Blackstone
terminated, or (b) any consultant or senior adviser that such SMD knows or
should know is under contract with Blackstone. For purposes of this Section
I.C., “solicit” means to have any direct or indirect communication of any kind
whatsoever, regardless of by whom initiated, inviting, advising, encouraging or
requesting any person or entity, in any manner, to terminate their employment or
business relationship with Blackstone, or recommending or suggesting (including
by identifying a person or entity to a third party) that a third party take any
of the foregoing actions.

 

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II. Confidentiality

A. Each SMD expressly agrees, at all times, during and subsequent to such SMD’s
service with Blackstone, to maintain the confidentiality of, and not to disclose
to or discuss with, any person any Confidential Information (as hereinafter
defined), except (i) to the extent reasonably necessary or appropriate to
perform such SMD’s duties and responsibilities as an SMD including without
limitation furthering the interests of Blackstone and/or developing new business
for Blackstone (provided that Confidential Information relating to (x) personnel
matters related to any present or former employee, partner or member of
Blackstone (including such SMD himself or herself), including compensation and
investment arrangements, or (y) the financial structure, financial position or
financial results of the Blackstone Entities, shall not be so used without the
prior consent of Blackstone), (ii) with the prior written consent of Blackstone,
or (iii) as otherwise required by law, regulation or legal process or by any
regulatory or self-regulatory organization having jurisdiction; provided that
such SMD agrees that a copy of the provisions set forth in Section I may be
disclosed to such SMD’s prospective future employers upon request in connection
with such SMD’s application for employment.

B. For purposes of this Non-Competition Agreement, “Confidential Information”
means information concerning the business, affairs, operations, strategies,
policies, procedures, organizational and personnel matters related to any
present or former employee, partner or member of Blackstone (including each SMD
himself or herself), including compensation and investment arrangements, terms
of agreements, financial structure, financial position, financial results or
other financial affairs, actual or proposed transactions or investments,
investment results, existing or prospective clients or investors, computer
programs or other confidential information related to the business of Blackstone
or to its members, actual or prospective clients or investors (including funds
managed by affiliates of Blackstone), their respective portfolio companies or
other third parties. Such information may have been or may be provided in
written or electronic form or orally. All of such information, from whatever
source learned or obtained and regardless of Blackstone’s connection to the
information, is referred to herein as “Confidential Information.” Confidential
Information excludes information that has been made generally available to the
public (although it does include any confidential information received by
Blackstone from any clients), but information that when viewed in isolation may
be publicly known or can be accessed by a member of the public will still
constitute Confidential Information for these purposes if such information has
become proprietary to Blackstone through Blackstone’s aggregation or
interpretation of such information. Without limiting the foregoing, Confidential
Information includes any information, whether public or not, which
(1) represents, or is aggregated in such a way as to represent, or purport to
represent, all or any portion of the investment results of, or any other
information about the investment “track record” of, (a) Blackstone, (b) a
business group of Blackstone, (c) one or more funds managed by Blackstone, or
(d) any individual or group of individuals during their time at Blackstone, or
(2) describes an individual’s role in achieving or contributing to any such
investment results.

III. Non-Disparagement

Each SMD agrees that, during and at any time after such SMD’s service with
Blackstone, such SMD will not, directly or indirectly, through any agent or
affiliate, make any disparaging comments or criticisms (whether of a
professional or personal nature) to any individual or other third party
(including without limitation any present or former member, partner or employee
of Blackstone) or entity regarding Blackstone (or the terms of any agreement or
arrangement of any Blackstone entity) or any of their respective affiliates,
members, partners or employees, or regarding such SMD’s relationship with
Blackstone or the termination of such relationship which, in each case, are
reasonably expected to result in material damage to the business or reputation
of Blackstone or any of its affiliates, members, partners or employees.

 

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IV. Remedies

A. Injunctive Relief. Each SMD acknowledges and agrees that Blackstone’s remedy
at law for any breach of the Restrictive Covenants would be inadequate and that
for any breach of such covenants, Blackstone shall, in addition to other
remedies as may be available to it at law or in equity, or as provided for in
this Non-Competition Agreement, be entitled to an injunction, restraining order
or other equitable relief, without the necessity of posting a bond, restraining
such SMD from committing or continuing to commit any violation of such
covenants. Each SMD agrees that proof shall not be required that monetary
damages for breach of the provisions of this Non-Competition Agreement would be
difficult to calculate and that remedies at law would be inadequate.

B. Forfeiture. In the event of any breach of this Non-Competition Agreement, the
SMD Agreement or any limited liability company agreement, partnership agreement
or other governing document of Blackstone to which such SMD is a party, or any
termination for Cause of such SMD’s services, (i) such SMD shall no longer be
entitled to receive payment of any amounts that would otherwise be payable to
such SMD following such SMD’s withdrawal as an SMD, member or partner, as the
case may be, of Blackstone (including, without limitation, return of such SMD’s
capital contributions), (ii) all of such SMD’s remaining SMD, member, partner or
other interests (including carried interests) in Blackstone (whether vested or
unvested and whether delivered or not yet delivered) shall immediately terminate
and be null and void and all of the securities of Blackstone Holdings or the
Blackstone Group L.P., a Delaware limited partnership (whether vested or
unvested and whether delivered or not yet delivered) held by such SMD or such
SMD’s personal planning vehicle(s) shall be forfeited, (iii) no further such
interests or securities will be awarded to such SMD, and (iv) all unrealized
gains (by investment) related to such SMD’s side by side investments will be
forfeited.

V. Amendment; Waiver

A. This Non-Competition Agreement may not be modified, other than by a written
agreement executed by each SMD and Blackstone, nor may any provision hereof be
waived other than by a writing executed by Blackstone.

B. The waiver by Blackstone of any particular default by each SMD or any
employee of Blackstone, shall not affect or impair the rights of Blackstone with
respect to any subsequent default of the same or of a different kind by such SMD
or any employee of Blackstone; nor shall any delay or omission by Blackstone to
exercise any right arising from any default by such SMD affect or impair any
rights that Blackstone may have with respect to the same or any future default
by such SMD or any employee of Blackstone.

VI. Governing Law

This Non-Competition Agreement and the rights and duties hereunder shall be
governed by and construed and enforced in accordance with the laws of the State
of New York.

VII. Resolution of Disputes; Submission to Jurisdiction; Waiver of Jury Trial

Any and all disputes which cannot be settled amicably, including any ancillary
claims of any party, arising out of, relating to or in connection with the
validity, negotiation, execution, interpretation, performance or non-performance
of this Non-Competition Agreement (including the validity, scope and
enforceability of this arbitration provision) or otherwise relating to
Blackstone (including, without limitation, any claim of discrimination in
connection with such SMD’s tenure as an SMD, partner or member of Blackstone or
any aspect of any relationship between such SMD and Blackstone or any

 

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termination of such SMD’s services as such member or partner or of any aspect of
any relationship between such SMD and Blackstone) shall be finally settled by
arbitration conducted by a single arbitrator in New York in accordance with the
then-existing Rules of Arbitration of the International Chamber of Commerce. If
the parties to the dispute fail to agree on the selection of an arbitrator
within thirty days of the receipt of the request for arbitration, the
International Chamber of Commerce shall make the appointment. The arbitrator
shall be a lawyer and shall conduct the proceedings in the English language.
Performance under this Non-Competition Agreement shall continue if reasonably
possible during any arbitration proceedings.

A. Notwithstanding the provisions of this Section VII, Blackstone may bring an
action or special proceeding in any court of competent jurisdiction for the
purpose of compelling a party to arbitrate, seeking temporary or preliminary
relief in aid of an arbitration hereunder and/or enforcing an arbitration award
and, for the purposes of this Section VII.A, each SMD (i) expressly consents to
the application of this Section to any such action or proceeding, (ii) agrees
that proof shall not be required that monetary damages for breach of the
provisions of this Non-Competition Agreement would be difficult to calculate and
that remedies at law would be inadequate, and (iii) irrevocably appoints the
Chief Legal Officer of Blackstone as such SMD’s agent for service of process in
connection with any such action or proceeding and agrees that service of process
upon such agent, who shall promptly advise such SMD of any such service of
process, shall be deemed in every respect effective service of process upon such
SMD in any such action or proceeding.

B. EACH SMD HEREBY IRREVOCABLY SUBMITS TO THE JURISDICTION OF COURTS LOCATED IN
NEW YORK, NEW YORK FOR THE PURPOSE OF ANY JUDICIAL PROCEEDING BROUGHT IN
ACCORDANCE WITH THE PROVISIONS OF SECTION VII.A, OR ANY JUDICIAL PROCEEDING
ANCILLARY TO AN ARBITRATION OR CONTEMPLATED ARBITRATION ARISING OUT OF OR
RELATING TO OR CONCERNING THIS NON-COMPETITION AGREEMENT. Such ancillary
judicial proceedings include any suit, action or proceeding to compel
arbitration, to obtain temporary or preliminary judicial relief in aid of
arbitration or to confirm an arbitration award. The parties acknowledge that the
forum designated by this Section VII.B will have a reasonable relation to this
Non-Competition Agreement, and to the parties’ relationship with one another.

C. Each SMD hereby waives, to the fullest extent permitted by applicable law,
any objection which such SMD now or hereafter may have to personal jurisdiction
or to the laying of venue of any such ancillary suit, action or proceeding
brought in any court referred to in Sections VII.A and VII.B and agrees not to
plead or claim the same.

D. Each SMD hereby agrees that such SMD shall not, nor shall such SMD allow
anyone acting on such SMD’s behalf to, subpoena or otherwise seek to gain access
to any financial statements or other confidential financial information relating
to Blackstone, or any of their respective members or partners, except as
specifically permitted by the terms of this Non-Competition Agreement or by the
provisions of any limited liability company agreement, partnership agreement or
other governing document of Blackstone to which such SMD is a party; provided,
that in any proceeding referred to in this Section VII, each SMD shall have the
right to use firm financial statements previously provided to such SMD to the
extent expressly provided in Section II of this Agreement.

VIII. Entire Agreement

This Non-Competition Agreement contains the entire agreement between the parties
with respect to the subject matter herein and supersedes all prior oral and
written agreements between the parties pertaining to such matters.

 

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IX. Severability

If any provision of this Non-Competition Agreement shall be held or deemed to be
invalid, illegal or unenforceable in any jurisdiction for any reason, the
invalidity of that provision shall not have the effect of rendering the
provision in question unenforceable in any other jurisdiction or in any other
case or of rendering any other provisions herein unenforceable, but the invalid
provision shall be substituted with a valid provision which most closely
approximates the intent and the economic effect of the invalid provision and
which would be enforceable to the maximum extent permitted in such jurisdiction
or in such case.

 

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WHEREOF, the parties hereto have duly executed this SMD Non-Competition and
Non-Solicitation Agreement as of the date first above written.

 

  BLACKSTONE HOLDINGS I L.P.   By:   Blackstone Holdings I/II GP Inc., its
general partner   By:  

/s/ Stephen A. Schwarzman

  Name:   Stephen A. Schwarzman   Title:   Chairman and Chief Executive Officer
  BLACKSTONE HOLDINGS II L.P.   By:   Blackstone Holdings I/II GP Inc., its
general partner   By:  

/s/ Stephen A. Schwarzman

  Name:   Stephen A. Schwarzman   Title:   Chairman and Chief Executive Officer
  BLACKSTONE HOLDINGS III L.P.   By:   Blackstone Holdings III GP L.L.C., its
general partner   By:  

/s/ Stephen A. Schwarzman

  Name:   Stephen A. Schwarzman   Title:   Chairman and Chief Executive Officer
  BLACKSTONE HOLDINGS IV L.P.   By:   Blackstone Holdings IV GP L.P., its
general partner   By:  

Blackstone Holdings IV GP Management L.L.C., its

general partner

  By:  

/s/ Stephen A. Schwarzman

  Name:   Stephen A. Schwarzman   Title:   Chairman and Chief Executive Officer
  BLACKSTONE HOLDINGS V L.P.   By:   Blackstone Holdings V GP L.P., its general
partner   By:  

Blackstone Holdings V GP Management (Delaware) L.P.,

its general partner

  By:  

Blackstone Holdings V GP Management L.L.C., its

general partner

  By:  

/s/ Stephen A. Schwarzman

  Name:   Stephen A. Schwarzman   Title:   Chairman and Chief Executive Officer

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Agreed and accepted as of the date

first above written:

By:  

/s/ Laurence A. Tosi

  (Please sign above) Print Name: Laurence A. Tosi