UNITED STATES  
  SECURITIES AND EXCHANGE COMMISSION  
  Washington, DC  20549  
     

SCHEDULE 13G

Under the Securities Exchange Act of 1934

(Amendment No. 1)*

 


Atara Biotherapeutics, Inc. (the “Issuer”)
(Name of Issuer)

Common Stock, $0.0001 par value per share (the “Shares”)
(Title of Class of Securities)
 
046513107
(CUSIP Number)
 
December 31, 2015
(Date of Event Which Requires Filing of this Statement)
 
 

 

Check the appropriate box to designate the rule pursuant to which this Schedule is filed:

☐ Rule 13d-1(b)

☐ Rule 13d-1(c)

☒ Rule 13d-1(d)

 

*The remainder of this cover page shall be filled out for a reporting person’s initial filing on this form with respect to the subject class of securities, and for any subsequent amendment containing information which would alter the disclosures provided in a prior cover page.
The information required in the remainder of this cover page shall not be deemed to be “filed” for the purpose of Section 18 of the Securities Exchange Act of 1934 (“Act”) or otherwise subject to the liabilities of that section of the Act but shall be subject to all other provisions of the Act (however, see the Notes).
 
 
CUSIP No. 046513107   Page 2 of 14 Pages

 

1 NAMES OF REPORTING PERSONS
I.R.S. IDENTIFICATION NO. OF ABOVE PERSON (ENTITIES ONLY)
  Carlos Slim Helú
2

CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP*

(a) o

(b) o

 

3 SEC USE ONLY
4 CITIZENSHIP OR PLACE OF ORGANIZATION
  México

NUMBER OF		 5 SOLE VOTING POWER
- 0 -
SHARES
BENEFICIALLY
OWNED BY		 6 SHARED VOTING POWER
616,153 Shares (See Item 4(c))
EACH
REPORTING		 7 SOLE DISPOSITIVE POWER
- 0 -
PERSON WITH 8 SHARED DISPOSITIVE POWER
616,153 Shares (See Item 4(c))
9 AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON
616,153 Shares (See Item 4(a))
10 CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES
CERTAIN SHARES* ☐
11 PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW 9
2.2% (See Item 4(b))
12 TYPE OF REPORTING PERSON*
IN
       

*SEE INSTRUCTIONS BEFORE FILLING OUT!

 
 
CUSIP No. 046513107   Page 3 of 14 Pages

 

1 NAMES OF REPORTING PERSONS
I.R.S. IDENTIFICATION NO. OF ABOVE PERSON (ENTITIES ONLY)
  Carlos Slim Domit
2

CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP*

(a) o

(b) o

3 SEC USE ONLY
4 CITIZENSHIP OR PLACE OF ORGANIZATION
  México

NUMBER OF		 5 SOLE VOTING POWER
- 0 -
SHARES
BENEFICIALLY
OWNED BY		 6 SHARED VOTING POWER
616,153 Shares (See Item 4(c))
EACH
REPORTING		 7 SOLE DISPOSITIVE POWER
- 0 -
PERSON WITH 8 SHARED DISPOSITIVE POWER
616,153 Shares  (See Item 4(c))
9 AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON
616,153 Shares (See Item 4(a))
10 CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES
CERTAIN SHARES* ☐
11 PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW 9
2.2% (See Item 4(b))
12 TYPE OF REPORTING PERSON*
IN
       

*SEE INSTRUCTIONS BEFORE FILLING OUT!

 
 
CUSIP No. 046513107   Page 4 of 14 Pages

 

1 NAMES OF REPORTING PERSONS
I.R.S. IDENTIFICATION NO. OF ABOVE PERSON (ENTITIES ONLY)
  Marco Antonio Slim Domit
2

CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP*

(a) o

(b) o

3 SEC USE ONLY
4 CITIZENSHIP OR PLACE OF ORGANIZATION
  México

NUMBER OF		 5 SOLE VOTING POWER
- 0 -
SHARES
BENEFICIALLY
OWNED BY		 6 SHARED VOTING POWER
616,153 Shares (See Item 4(c))
EACH
REPORTING		 7 SOLE DISPOSITIVE POWER
- 0 -
PERSON WITH 8 SHARED DISPOSITIVE POWER
616,153 Shares  (See Item 4(c))
9 AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON
616,153 Shares (See Item 4(a))
10 CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES
CERTAIN SHARES* ☐
11 PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW 9
2.2% (See Item 4(b))
12 TYPE OF REPORTING PERSON*
IN
       

*SEE INSTRUCTIONS BEFORE FILLING OUT!

 
 
CUSIP No. 046513107   Page 5 of 14 Pages

 


1		 NAMES OF REPORTING PERSONS
I.R.S. IDENTIFICATION NO. OF ABOVE PERSON (ENTITIES ONLY)
  Patrick Slim Domit
2

CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP*

(a) o

(b) o

3 SEC USE ONLY
4 CITIZENSHIP OR PLACE OF ORGANIZATION
  México

NUMBER OF		 5 SOLE VOTING POWER
- 0 -
SHARES
BENEFICIALLY
OWNED BY		 6 SHARED VOTING POWER
616,153 Shares (See Item 4(c))
EACH
REPORTING		 7 SOLE DISPOSITIVE POWER
- 0 -
PERSON WITH 8 SHARED DISPOSITIVE POWER
616,153 Shares  (See Item 4(c))
9 AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON
616,153 Shares (See Item 4(a))
10 CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES
CERTAIN SHARES* ☐
11 PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW 9
2.2% (See Item 4(b))
12 TYPE OF REPORTING PERSON*
IN
       

*SEE INSTRUCTIONS BEFORE FILLING OUT!

 
 
CUSIP No. 046513107   Page 6 of 14 Pages

 

1 NAMES OF REPORTING PERSONS
I.R.S. IDENTIFICATION NO. OF ABOVE PERSON (ENTITIES ONLY)
  María Soumaya Slim Domit
2

CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP*

(a) o

(b) o

3 SEC USE ONLY
4 CITIZENSHIP OR PLACE OF ORGANIZATION
  México

NUMBER OF		 5 SOLE VOTING POWER
- 0 -
SHARES
BENEFICIALLY
OWNED BY		 6 SHARED VOTING POWER
616,153 Shares (See Item 4(c))
EACH
REPORTING		 7 SOLE DISPOSITIVE POWER
- 0 -
PERSON WITH 8 SHARED DISPOSITIVE POWER
616,153 Shares  (See Item 4(c))
9 AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON
616,153 Shares (See Item 4(a))
10 CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES
CERTAIN SHARES* ☐
11 PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW 9
2.2% (See Item 4(b))
12 TYPE OF REPORTING PERSON*
IN
       

*SEE INSTRUCTIONS BEFORE FILLING OUT!

 
 
CUSIP No. 046513107   Page 7 of 14 Pages

 

1 NAMES OF REPORTING PERSONS
I.R.S. IDENTIFICATION NO. OF ABOVE PERSON (ENTITIES ONLY)
  Vanessa Paola Slim Domit
2

CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP*

(a) o

(b) o

3 SEC USE ONLY
4 CITIZENSHIP OR PLACE OF ORGANIZATION
  México

NUMBER OF		 5 SOLE VOTING POWER
- 0 -
SHARES
BENEFICIALLY
OWNED BY		 6 SHARED VOTING POWER
616,153 Shares (See Item 4(c))
EACH
REPORTING		 7 SOLE DISPOSITIVE POWER
- 0 -
PERSON WITH 8 SHARED DISPOSITIVE POWER
616,153 Shares  (See Item 4(c))
9 AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON
616,153 Shares (See Item 4(a))
10 CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES
CERTAIN SHARES* ☐
11 PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW 9
2.2% (See Item 4(b))
12 TYPE OF REPORTING PERSON*
IN
       

*SEE INSTRUCTIONS BEFORE FILLING OUT!

 
 
CUSIP No. 046513107   Page 8 of 14 Pages

 

1 NAMES OF REPORTING PERSONS
I.R.S. IDENTIFICATION NO. OF ABOVE PERSON (ENTITIES ONLY)
  Johanna Monique Slim Domit
2

CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP*

(a) o

(b) o

3 SEC USE ONLY
4 CITIZENSHIP OR PLACE OF ORGANIZATION
  México

NUMBER OF		 5 SOLE VOTING POWER
- 0 -
SHARES
BENEFICIALLY
OWNED BY		 6 SHARED VOTING POWER
616,153 Shares (See Item 4(c))
EACH
REPORTING		 7 SOLE DISPOSITIVE POWER
- 0 -
PERSON WITH 8 SHARED DISPOSITIVE POWER
616,153 Shares  (See Item 4(c))
9 AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON
616,153 Shares (See Item 4(a))
10 CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES
CERTAIN SHARES* ☐
11 PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW 9
2.2% (See Item 4(b))
12 TYPE OF REPORTING PERSON*
IN
       

*SEE INSTRUCTIONS BEFORE FILLING OUT!

 
 
CUSIP No. 046513107   Page 9 of 14 Pages

 


1		 NAMES OF REPORTING PERSONS
I.R.S. IDENTIFICATION NO. OF ABOVE PERSON (ENTITIES ONLY)
  Inversora Carso, S.A. de C.V., formerly known as Inmobiliaria Carso, S.A. de C.V.
2

CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP*

(a) o

(b) o

3 SEC USE ONLY
4 CITIZENSHIP OR PLACE OF ORGANIZATION
  México

NUMBER OF		 5 SOLE VOTING POWER
- 0 -
SHARES
BENEFICIALLY
OWNED BY		 6 SHARED VOTING POWER
616,153 Shares (See Item 4(c))
EACH
REPORTING		 7 SOLE DISPOSITIVE POWER
- 0 -
PERSON WITH 8 SHARED DISPOSITIVE POWER
616,153 Shares  (See Item 4(c))
9 AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON
616,153 Shares (See Item 4(a))
10 CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES
CERTAIN SHARES* ☐
11 PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW 9
2.2% (See Item 4(b))
12 TYPE OF REPORTING PERSON*
HC
       

*SEE INSTRUCTIONS BEFORE FILLING OUT

 

 
 
CUSIP No. 046513107   Page 10 of 14 Pages

 

 

 


Item 1.		  
(a)

Name of Issuer:

Atara Biotherapeutics, Inc. (the “Issuer”)

(b)

Address of Issuer’s Principal Executive Offices:

701 Gateway Blvd., Suite 200

South San Francisco, CA 94080

Item 2.  
(a)

Name of Persons Filing:

This statement is filed pursuant to Rule 13d-1(d) under the U.S. Securities Exchange Act of 1934, as amended (the “Act”), by the persons listed below (the “Reporting Persons”).

(1)

 

Carlos Slim Helú, Carlos Slim Domit, Marco Antonio Slim Domit, Patrick Slim Domit, María Soumaya Slim Domit, Vanessa Paola Slim Domit and Johanna Monique Slim Domit (collectively, the “Slim Family”). The members of the Slim Family are beneficiaries of a Mexican trust which in turn owns all of the outstanding voting securities of Inversora Carso, S.A. de C.V., formerly known as Inmobiliaria Carso, SA. de C.V. (“Inversora Carso”).

 

(2)

 

Inversora Carso, a sociedad anónima de capital variable organized under the laws of the United Mexican States (“Mexico”), is a holding company with portfolio investments in various companies. Inversora Carso owns all of the outstanding voting securities of Control Empresarial de Capitales S.A. de C.V.

 

(b)

Address of Principal Business Office:

(i) The principal business address for each member of the Slim Family is:

Paseo de las Palmas 736
Colonia Lomas de Chapultepec
11000 México D.F.
México


(ii) Inversora Carso’s principal business address is:

Lago Zurich 245
Presa Falcon, Piso 20
Colonia Granada Ampliación
11529 México D.F.
México

(c)

Citizenship:

Each member of the Slim Family is a Mexican citizen and Inversora Carso is a Mexican corporation.

 

 
 

 

CUSIP No. 046513107   Page 11 of 14 Pages

 

 

(d)

Title of Class of Securities:

Common Stock, $0.0001 par value per share (the “Shares”)

(e)

CUSIP Number:

046513107

Item 3. If this statement is filed pursuant to Rule 13d-1(b), or 13d-2(b) or (c), check whether the person filing is a(n):
(a)   Broker or dealer registered under Section 15 of the Act;
     
(b)   Bank as defined in Section 3(a)(6) of the Act;
     
(c)   Insurance company as defined in Section 3(a)(19) of the Act;
     
(d)   Investment company registered under Section 8 of the Investment Company Act;
     
(e)   Investment adviser in accordance with Rule 13d-1(b)(1)(ii)(E);
 
(f)   Employee benefit plan or endowment fund in accordance with Rule 13d-1(b)(1)(ii)(F);
     
(g)   Parent holding company or control person in accordance with Rule 13d-1(b)(1)(ii)(G);
     
(h)   Savings association as defined in Section 3(b) of the Federal Deposit Insurance Act;
 
(i)  

Church plan that is excluded from the definition of an investment company under Section 3(c)(14) of the Investment Company Act; or

 

 
(j)   Group, in accordance with Rule 13d-1(b)(1)(ii)(J).
Item 4. Ownership.
(a)

Amount Beneficially Owned:

As of the date of this filing, (i) Inversora Carso, directly or indirectly, owns 616,153 Shares, and (ii) the Slim Family, which are beneficiaries of a Mexican trust that in turn owns all of the issued and outstanding voting equity securities of Inversora Carso, may be deemed to beneficially own indirectly the Shares beneficially owned, directly or indirectly, by Inversora Carso.

(b) Percent of Class:
 

The Shares beneficially owned by the Slim Family constitute approximately 2.2% of the 28,631,144 issued and outstanding Shares, as reported in the Form 10-Q filed by the Issuer with the Securities and Exchange Commission on November 6, 2015.

The Shares beneficially owned by Inversora Carso constitute approximately 2.2% of the 28,631,144 issued and outstanding Shares, as reported in the Form 10-Q filed by the Issuer with the Securities and Exchange Commission on November 6, 2015.

(c) Number of shares as to which such person has:
  (i) Sole power to vote or to direct the vote: -0-

 

 
 
CUSIP No. 046513107   Page 12 of 14 Pages

 

(ii)

Shared power to vote or to direct the vote:

As to the Slim Family: 616,153 Shares

As to Inversora Carso: 616,153 Shares

 
 (iii)

Sole power to dispose or to direct the disposition of: -0-

 
(iv)

Shared power to dispose or direct the disposition of:

As to the Slim Family: 616,153 Shares

As to Inversora Carso: 616,153 Shares

Item 5. Ownership of Five Percent or Less of a Class.
If this statement is being filed to report the fact that as of the date hereof the reporting person has ceased to be the beneficial owner of more than five percent of the class of securities, check the following: ☒    
   
Item 6.

Ownership of More than Five Percent on Behalf of Another Person.

Not applicable.

Item 7.

Identification and Classification of the Subsidiary Which Acquired the Security Being Reported on by the Parent Holding Company.

Shares reported as beneficially owned by Inversora Carso include Shares owned by its subsidiary, Control Empresarial de Capitales, S.A. de C.V.

Item 8.

Identification and Classification of Members of the Group.

The identity of each member of the group filing this schedule is as follows: Carlos Slim Helú, Carlos Slim Domit, Marco Antonio Slim Domit, Patrick Slim Domit, María Soumaya Slim Domit, Vanessa Paola Slim Domit, Johanna Monique Slim Domit, and Inversora Carso, S.A. de C.V.

Item 9.

Notice of Dissolution of Group.

Not applicable.

Item 10. Certifications.
By signing below I certify that, to the best of my knowledge and belief, the securities referred to above were not acquired and are not held for the purpose of or with the effect of changing or influencing the control of the issuer of the securities and were not acquired and are not held in connection with or as a participant in any transaction having that purpose or effect, other than activities solely in connection with a nomination under §240.14a-11.
           

 

The Powers of Attorney for the members of the Slim Family, Inversora Carso and GFI, which are filed as exhibits to Amendment No. 1 to the Schedule 13G filed by the Reporting Persons with the Securities and Exchange Commission on February 14, 2014 in respect of their ownership in equity shares of YPF

 

 
 
CUSIP No. 046513107   Page 13 of 14 Pages

 

Sociedad Anónima and the Joint Filing Agreement, which is filed as an exhibit to the Schedule 13G filed by the Reporting Persons with the Securities and Exchange Commission on February 17, 2015 in respect of their ownership of Shares, are hereby incorporated herein by reference.

 
 
CUSIP No. 046513107   Page 14 of 14 Pages

 

SIGNATURE

After reasonable inquiry and to the best of my knowledge and belief, I certify that the information set forth in this statement is true, complete and correct.

   
 
Carlos Slim Helú  
                                                               
Carlos Slim Domit By: /s/ Raul Humberto Zepeda Ruiz      
                                                              Raul Humberto Zepeda Ruiz
Marco Antonio Slim Domit Attorney-in-Fact
                                                              February 16, 2016
Patrick Slim Domit  
                                                               
María Soumaya Slim Domit  
                                                                
Vanessa Paola Slim Domit  
                                                                
Johanna Monique Slim Domit  
 
   
INVERSORA CARSO, S.A. DE C.V.  

 

/s/ Raul Humberto Zepeda Ruiz              

  

By: Raul Humberto Zepeda Ruiz

Title: Attorney-in-Fact