UNITED STATES
SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549
 
FORM 8-A
 
FOR REGISTRATION OF CERTAIN CLASSES OF SECURITIES
PURSUANT TO SECTION 12 (b) OR (g) OF THE
SECURITIES EXCHANGE ACT OF 1934
 
 
DFA INVESTMENT DIMENSIONS GROUP INC.  
(Exact name of registrant as specified in its charter)
 
Maryland                                                                                                              See Below
         (State of incorporation or organization)                        (I.R.S Employer Identification No.)         
 
6300 Bee Cave Road, Building One, Austin, TX                                                         78746 
(Address of principal executive offices)                                                                 (Zip Code)
 
 
 
 
 
Securities to be registered pursuant to Section 12(b) of the Act:
 
Title of each class
to be so registered
Name of each exchange on which
each class is to be registered
Shares of common stock, par value of one cent ($0.01)
 
U.S. Core Equity 1 Portfolio: ETF Class Shares 
NYSE Arca, Inc
U.S. High Relative Profitability Portfolio: ETF Class Shares 
NYSE Arca, Inc
U.S. Small Cap Value Portfolio: ETF Class Shares 
NYSE Arca, Inc
U.S. Vector Equity Portfolio: ETF Class Shares 
NYSE Arca, Inc
DFA Real Estate Securities Portfolio: ETF Class Shares 
NYSE Arca, Inc
 
If this form relates to the registration of a class of securities pursuant to Section 12(b) of the Exchange Act and is effective pursuant to General Instruction A.(c) or (e), check the following box. [X]
 
If this form relates to the registration of a class of securities pursuant to Section 12(g) of the Exchange Act and is effective pursuant to General Instruction A.(d) or (e), check the following box. [  ]
 
If this form relates to the registration of a class of securities concurrently with a Regulation A offering, check the following box. [  ]
 
Securities Act registration statement or Regulation A offering statement file number to which this form relates: 002-73948
 
Securities to be registered pursuant to Section 12 (g) of the Act:  
 
 
None
(Title of class)
 
 
1
 
 
INFORMATION REQUIRED IN REGISTRATION STATEMENT
 
Item 1.
Descriptions of Registrant’s Securities to be Registered.
 
 
 
A description of the class of shares of common stock, par value of one cent ($0.01), of the series of DFA Investment Dimensions Group Inc. (the “Fund”) listed below to be registered hereunder is set forth in Post-Effective Amendment No. 266 to the Fund’s Registration Statement on Form N-1A (Commission File Nos. 002-73948; 811-03258), as filed with the Securities and Exchange Commission on February 27, 2026, which description is incorporated herein by reference.
 
 
 
The classes of the series of the Fund that are registering securities, and their I.R.S. Employer Identification Numbers, are as follows:
 
U.S. Core Equity 1 Portfolio: ETF Class Shares 
US25239Y2202
U.S. High Relative Profitability Portfolio: ETF Class Shares 
US25239Y1964 
U.S. Small Cap Value Portfolio: ETF Class Shares 
US25239Y1709 
U.S. Vector Equity Portfolio: ETF Class Shares 
US25239Y1543 
DFA Real Estate Securities Portfolio: ETF Class Shares 
US25239Y1477 
 
Item 2.
Exhibits
 
1.
The Fund’s Articles of Amendment and Restatement is incorporated herein by reference to Exhibit (a)(1) to the Fund’s Registration Statement on Form N-1A (Commission File Nos. 002-73948; 811-03258), as filed with the Securities and Exchange Commission on February 27, 2026. 
2.
The Fund’s Articles Supplementary to the Charter is incorporated herein by reference to Exhibit (a)(2) to the Fund’s Registration Statement on Form N-1A (Commission File Nos. 002-73948; 811-03258), as filed with the Securities and Exchange Commission on February 27, 2026.  
3.
The Fund’s Articles of Amendment to the Charter is incorporated herein by reference to Exhibit (a)(3) to the Fund’s Registration Statement on Form N-1A (Commission File Nos. 002-73948; 811-03258), as filed with the Securities and Exchange Commission on February 27, 2026.
4.
The Fund’s Amended and Restated Bylaws are incorporated herein by reference to Exhibit (b) to the Fund’s Registration Statement on Form N-1A (Commission File Nos. 002-73948; 811-03258), as filed with the Securities and Exchange Commission on January 25, 2022.
 
SIGNATURE
 
 
 
Pursuant to the requirements of Section 12 of the Securities Exchange Act of 1934, the registrant has duly caused this registration statement to be signed on its behalf by the undersigned, thereto duly authorized, as of this 22nd day of September, 2026.
 
 
 
 
 
DFA INVESTMENT DIMENSIONS GROUP INC.
 
 
 
 
 
 
By:
/s/ Ryan P. Buechner
 
 
 
 
 
Name:  Ryan P. Buechner
 
 
 
 
 
Title:
Vice President and Assistant Secretary