<Page>
EFFECTIVE DATE: OCTOBER 5, 2004
5. CODE OF BUSINESS ETHICS FOR PRINCIPAL EXECUTIVE AND FINANCIAL OFFICERS
DFA INVESTMENT DIMENSIONS GROUP INC.
DIMENSIONAL EMERGING MARKETS VALUE FUND INC.
DIMENSIONAL INVESTMENT GROUP INC.
THE DFA INVESTMENT TRUST COMPANY
I. COVERED OFFICERS AND PURPOSES OF THE CODE
The Boards of Directors/Trustees (together, the "Boards") of DFA
Investment Dimensions Group Inc., Dimensional Emerging Markets Value Fund
Inc., Dimensional Investment Group Inc. and The DFA Investment Trust Company
(each a "Fund," and together, the "Funds") have adopted this Code of Business
Ethics for Principal Executive and Financial Officers (the "Code"). The Code
applies to the Funds' principal executive officers and principal financial
officers (together, the "Covered Officers"), and is adopted to promote:
- honest and ethical conduct, including the ethical handling of conflicts
of interest;
- full, fair, accurate, timely and understandable disclosure in reports
and documents that a Fund files with, or submits to, the U.S. Securities
and Exchange Commission (the "SEC"), and in other public communications
made by the Funds;
- compliance with applicable laws and governmental rules and regulations;
- the prompt internal reporting of violations of the Code to the
appropriate person(s) identified in the Code; and
- accountability for adherence to the Code.
II. COVERED OFFICERS SHOULD "ADHERE TO A HIGH STANDARD OF BUSINESS ETHICS"
Each Covered Officer owes a duty to the Funds to adhere to a high
standard of business ethics and should be sensitive to situations that may
give rise to actual, as well as apparent, conflicts of interests.
Each Covered Officer shall:
- observe all laws and governmental rules and regulations, accounting
standards and Fund policies;
- adhere to a high standard of business ethics; and
- place the interests of the Funds before the Covered Officer's own
personal interests.
All activities of Covered Officers should be guided by and adhere to
these fiduciary standards.
III. COVERED OFFICERS SHOULD HANDLE ETHICALLY CONFLICTS OF INTEREST
GUIDING PRINCIPLES. A "conflict of interest" occurs when a Covered
Officer's private interests interfere with the interests of, or his service
to, the Funds. A conflict of interest can arise when a Covered Officer takes
actions or has interests that may make it difficult to perform his Fund work
objectively and effectively. For example, a conflict of interest would arise
if a Covered Officer, or a member of his family, receives improper personal
benefits as a result of his positions with the Funds. In addition, the Funds
must be sensitive to situations that create apparent, if not actual,
conflicts of interest. Service to the Funds should not be subordinated to
personal gain and advantage.
Certain conflicts of interest covered by this Code arise out of the
relationships between Covered Officers and the Funds that already are subject
to conflict of interest provisions in the Investment Company Act of 1940, as
amended (the "1940 Act"), and the Investment Advisers Act of 1940, as amended
(the "Advisers Act"). For example, Covered Officers may not individually
engage in certain transactions (such as the purchase or sale of securities or
other property) with the Funds because of the Covered Officers' status as
"affiliated persons" of the Funds. The compliance programs and procedures
1
<Page>
of the Funds and Dimensional Fund Advisors Inc., the Funds' investment
advisor and administrator (the "Advisor"), are designed to prevent, or
identify and correct, violations of these provisions. This Code does not,
and is not intended to, repeat or replace those compliance programs and
procedures. Covered Officers must in all cases comply with applicable
statutes and regulations.
Although typically not presenting an opportunity for improper personal
benefit, conflicts of interest arise from, or as a result of, the contractual
relationships between the Funds and the Advisor, of which the Covered
Officers are also officers or employees. As a result, it is recognized by
the Boards that, subject to the Advisor's fiduciary duties to the Funds, the
Covered Officers will, in the normal course of their duties (whether formally
for the Funds or for the Advisor, or for both), be involved in establishing
policies and implementing decisions that will have different effects on the
Advisor and the Funds. The Boards recognize that the participation of the
Covered Officers in such activities is inherent in the contractual
relationships between the Funds and the Advisor, and is consistent with the
expectation of the Boards of the performance by the Covered Officers of their
duties as officers of the Funds. Such participation, if addressed in
conformity with the provisions of the 1940 Act and the Advisers Act, will be
deemed to have been handled ethically. In addition, it is recognized by the
Boards that the Covered Officers may also be officers or employees of one or
more other investment companies advised by the Advisor and covered by this or
other Codes.
Other conflicts of interest are covered by the Code, even if such
conflicts of interest are not subject to provisions in the 1940 Act and the
Advisers Act. In reading the following examples of conflicts of interest
under the Code, the Covered Officers should keep in mind that such a list
cannot be exhaustive by covering every possible scenario. It follows that
the overarching principle-that the personal interest of a Covered Officer
should not be placed improperly before the interest of a Fund-should be the
guiding principle in all circumstances.
Each Covered Officer must:
- avoid conflicts of interest whenever possible;
- handle any actual or apparent conflict of interest ethically;
- not use his personal influence or personal relationships improperly to
influence investment decisions or financial reporting by the Funds whereby
the Covered Officer would benefit personally to the detriment of the Funds;
- not cause the Funds to take action, or fail to take action, for the
individual personal benefit of the Covered Officer rather than for the
benefit of the Funds;
- not use material, non-public knowledge of portfolio transactions made or
contemplated for the Funds to profit personally, or to cause others to
profit, by the market effect of such transactions; and
- as described in more detail below, discuss any material transaction or
relationship, which could reasonably be expected to give rise to a
conflict of interest, with Rex A. Sinquefield, the Funds' Co-Chairman
(the "Designated Ethics Officer"). In the event Mr. Sinquefield is not
available, the Chairman of the Audit Committee may take action required
hereunder of the Designated Ethics Officer.
There are some conflict of interest situations that should always be
discussed with the Designated Ethics Officer, if material. Examples of these
situations include:
- any outside business activity that detracts from an individual's ability
to devote appropriate time and attention to his responsibilities with the
Funds;
- service as a director on the board of any public or private company;
- the receipt of any non-nominal gifts;
- the receipt of any entertainment from any company with which the Funds
have current or prospective business dealings, unless such entertainment
is business-related, reasonable in cost, appropriate as to time and place,
and not so frequent as to raise any question of impropriety;
2
<Page>
- being in the position of supervising, reviewing or having any influence
on the job evaluation, pay or benefit of any immediate family member;
- any ownership interest in, or any consulting or employment relationship
with, any of the Funds' service providers, other than the Advisor and DFA
Securities Inc. ("DFAS"), or any affiliated person thereof; and
- a direct or indirect financial interest in commissions, transaction
charges or spreads paid by a Fund for effecting portfolio transactions or
for selling or redeeming shares other than an interest arising from the
Covered Officer's employment, such as compensation or equity ownership.
IV. DISCLOSURE
Each Covered Officer is required to be familiar and comply with the
Funds' disclosure controls and procedures so that the Funds' subject reports
and documents filed with the SEC comply in all material respects with the
applicable federal securities laws and SEC rules. In addition, each Covered
Officer having direct or supervisory authority regarding these SEC filings or
the Funds' other public communications should, to the extent appropriate
within his area of responsibility, consult with other Fund officers and
employees and take other appropriate steps regarding these disclosures with
the goal of making full, fair, accurate, timely and understandable disclosure.
Each Covered Officer:
- must familiarize himself with the disclosure requirements applicable to
the Funds as well as the business and financial operations of the Funds;
and
- must not knowingly misrepresent, or intentionally cause others to
misrepresent, facts about the Funds to others, whether within or
outside the Funds, including to the Funds' directors/trustees and
auditors, and to governmental regulators and self-regulatory organizations.
V. Compliance
It is the Funds' policy to comply with all applicable laws and
governmental rules and regulations. It is the responsibility of each Covered
Officer to adhere to the standards and restrictions imposed by those laws,
rules and regulations, including those relating to affiliated transactions,
accounting and auditing matters.
VI. Reporting and Accountability
Each Covered Officer must:
- upon adoption of the Code, affirm in writing to the Designated Ethics
Officer that he has received, read, and understands the Code;
- annually thereafter affirm to the Designated Ethics Officer that he has
received, read and understands the Code and has complied with the
requirements of the Code;
- not retaliate against any employee or Covered Officer for reports of
potential violations that are made in good faith; and
- notify the Designated Ethics Officer promptly if the Covered Officer
knows of any violation of this Code. Failure to do so is itself a
violation of this Code.
The Designated Ethics Officer is responsible for applying the
provisions of the Code to specific situations in which questions arise under
the Code, and the Designated Ethics Officer has the authority to interpret
this Code in any particular situation. The Designated Ethics Officer is
authorized (and encouraged) to consult, as appropriate, with the Audit
Committee of the Funds, the members of the Boards who are not "interested
persons" (together, the "Independent Directors"), and counsel to the Funds
and the Independent Directors.
The Funds will comply with the following procedures in investigating
and enforcing this Code:
3
<Page>
- the Designated Ethics Officer will take all appropriate action to
investigate any violations and potential violations reported to him;
- violations and potential violations will be reported to the Audit
Committee after such investigation;
- if the Audit Committee determines that a violation of this Code has
occurred, the Audit Committee will consider appropriate action, which
may include the review of, and necessary modifications to, applicable
policies and procedures; notification to appropriate personnel of the
Advisor or the Advisor's board of directors; or recommending the
dismissal of the Covered Officer;
- appropriate disciplinary or preventive action may include a letter of
censure, suspension, dismissal or, in the event of criminal or other
serious violations of law, notification of the SEC or other appropriate
law enforcement authorities;
- the Audit Committee will report to the Boards any action (whether
disciplinary, preventive or otherwise) taken to address violations of
this Code;
- the Audit Committee will be responsible for granting waivers and
determining sanctions, as appropriate; and
- any changes to or waivers of this Code will, to the extent required, be
disclosed on Form N-CSR as provided by SEC rules.
VII. OTHER POLICIES AND PROCEDURES
The code of ethics under Rule 17j 1 under the 1940 Act, adopted by the
Funds, the Advisor and the affiliated companies of the Advisor, and the
Advisor's policies and procedures set forth in the STATEMENT OF POLICY OF
EMPLOYEE TRADING are separate requirements applying to the Covered Officers
and others, and are not part of this Code.
VIII. AMENDMENTS
This Code may not be amended except in written form, which is
specifically approved or ratified by a majority vote of the Boards, including
a majority of the Independent Directors.
IX. CONFIDENTIALITY
All reports and records prepared or maintained pursuant to this Code
shall be considered confidential and shall be maintained and protected
accordingly. Except as otherwise required by law or this Code, such matters
shall not be disclosed to anyone other than the members of the Boards and
their counsel, the Funds, and the Advisor.
X. INTERNAL USE
The Code is intended solely for the internal use by the Funds and does
not constitute an admission, by or on behalf of any Fund, as to any fact,
circumstance, or legal conclusion.
Date: June 26, 2003
4
<Page>
Exhibit A
PERSONS COVERED BY THIS CODE OF BUSINESS ETHICS
-----------------------------------------------
David G. Booth (Principal Executive Officer of the Funds)
Michael T. Scardina (Principal Financial Officer of the Funds)
A-1