DFA Investment Dimensions Group Inc.

09/28/2026 | Press release | Distributed by Public on 09/28/2026 08:38

Prospectus by Investment Company (Form 497)

DFA Investment Dimensions Group Inc.

U.S. Large Cap Equity Portfolio

U.S. Small Cap Value Portfolio

U.S. Targeted Value Portfolio

U.S. Core Equity 1 Portfolio

U.S. Core Equity 2 Portfolio

U.S. Vector Equity Portfolio

U.S. Small Cap Portfolio

U.S. Micro Cap Portfolio

U.S. High Relative Profitability Portfolio

DFA Real Estate Securities Portfolio

U.S. Large Cap Growth Portfolio

U.S. Small Cap Growth Portfolio

Dimensional Investment Group Inc.

U.S. Large Company Portfolio

SUPPLEMENT TO THE CURRENTLY EFFECTIVE
PROSPECTUSES AND STATEMENTS OF ADDITIONAL INFORMATION

Effective September 28, 2026, the disclosure on the cover page of the currently effective Prospectuses and Statements of Additional Information ("SAIs") of the portfolios listed above, each a series of DFA Investment Dimensions Group Inc. or Dimensional Investment Group Inc, regarding the offering of ETF class shares is replaced with the following. Capitalized terms not otherwise defined in this supplement have the meanings assigned to them in the Prospectuses and SAIs.

The following Portfolios began offering ETF Class shares on the dates listed below:

Portfolio

Commencement of ETF Class Shares Offering

U.S. Micro Cap Portfolio

March 20, 2026

U.S. Small Cap Growth Portfolio

May 6, 2026

U.S. Large Company Portfolio

August 5, 2026

U.S. Small Cap Value Portfolio

September 28, 2026

U.S. Core Equity 1 Portfolio

September 28, 2026

U.S. Vector Equity Portfolio

September 28, 2026

U.S. High Relative Profitability Portfolio

September 28, 2026

DFA Real Estate Securities Portfolio

September 28, 2026

The Fund has registered ETF Class Shares for the U.S. Large Cap Equity Portfolio, U.S. Targeted Value Portfolio, U.S. Core Equity 2 Portfolio, U.S. Small Cap Portfolio, and U.S. Large Cap Growth Portfolio, but they are not offered for sale at this time.

The date of this Supplement is September 28, 2026

DFA Investment Dimensions Group Inc. published this content on September 28, 2026, and is solely responsible for the information contained herein. Distributed via EDGAR on September 28, 2026 at 14:38 UTC. If you believe the information included in the content is inaccurate or outdated and requires editing or removal, please contact us at [email protected]