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                       SECURITIES AND EXCHANGE COMMISSION
                             Washington, D.C. 20549
                                  -----------
                                   SCHEDULE TO
                                 AMENDMENT NO. 9

           TENDER OFFER STATEMENT UNDER SECTION 14(d)(1) or 13(e)(1)
                     OF THE SECURITIES EXCHANGE ACT OF 1934

                                 EON LABS, INC.
                            (Name of Subject Company)

                                   NOVARTIS AG
                              NOVARTIS CORPORATION
                            ZODNAS ACQUISITION CORP.
                       (Name of Filing Persons--Offerors)

                          COMMON STOCK, PAR VALUE $0.01
                         (Title of Class of Securities)

                                    29412E100
                      (CUSIP Number of Class of Securities)

                                  George Miller
                        Head of Legal and General Affairs
                                   Novartis AG
                                 35 Lichtstrasse
                           CH-4002 Basel, Switzerland
                                 41-61-324-1111
           (Name, Address and Telephone Number of Person Authorized
      to Receive Notices and Communications on Behalf of Filing Persons)

                                   -Copies to-
                           Andrew R. Brownstein, Esq.
                             Trevor S. Norwitz, Esq.
                         Wachtell, Lipton, Rosen & Katz
                               51 West 52nd Street
                               New York, NY 10019
                                 (212) 403-1000
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                            CALCULATION OF FILING FEE

              Transaction Valuation          Amount of Filing Fee
              ---------------------------------------------------
                   $977,098,158*                  $115,005*
              ---------------------------------------------------
*  Estimated for purposes of calculating the amount of the filing fee only. The
   calculation of the filing fee is described on the cover page to Amendment No.
   1 to the Schedule TO filed on May 27, 2005.

[X]Check the box if any part of the fee is offset as provided by Rule
   0-11(a)(2) and identify the filing with which the offsetting fee was
   previously paid. Identify the previous filing by registration statement
   number, or the Form or Schedule and the date of its filing.

      Amount Previously Paid:    $115,005          Filing Party:  Novartis Corp.
      Form or Registration No.:  Schedule TO       Date Filed:  May 23, 2005

[_]Check the box if the filing relates solely to preliminary communications
   made before the commencement of a tender offer.
Check the appropriate boxes below to designate any transactions to which the
   statement relates:
[X] third-party tender offer subject to Rule 14d-1.
[_] issuer tender offer subject to Rule 13e-4.
[_] going-private transaction subject to Rule 13e-3.
[_] amendment to Schedule 13D under Rule 13d-2.
Check the following box if the filing is a final amendment reporting the results
of the tender offer: [_]
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           This Amendment No. 9 amends and supplements the Tender Offer
Statement on Schedule TO, as amended, (the "SCHEDULE TO"), originally filed with
the Securities and Exchange Commission on May 23, 2005 and as amended and
supplemented by Amendment No. 1 on May 27, 2005, Amendment No. 2 on June 2,
2005, Amendment No. 3 on June 7, 2005, Amendment No. 4 on June 15, 2005,
Amendment No. 5 on June 21, 2005, Amendment No. 6 on July 5, 2005, Amendment No.
7 on July 8, 2005, and Amendment No. 8 on July 19, 2005 by Novartis AG, a Swiss
Corporation, Novartis Corporation ("NOVARTIS US"), a New York corporation and an
indirect wholly owned subsidiary of Novartis AG, and Zodnas Acquisition Corp.
("ZODNAS"), a Delaware corporation and an indirect wholly owned subsidiary of
Novartis US. The Schedule TO relates to the offer by Zodnas to purchase any and
all of the outstanding shares of common stock, par value $0.01 per share (the
"SHARES"), of Eon Labs, Inc., a Delaware corporation ("EON"), for $31.00 per
Share, net to the seller in cash, upon the terms and subject to the conditions
set forth in the Offer to Purchase, dated May 23, 2005 (the "OFFER TO
PURCHASE"), and in the related Letter of Transmittal. Copies of the Offer to
Purchase and the related Letter of Transmittal are filed with the Schedule TO as
exhibits (a)(1)(A) and (a)(1)(B), respectively. Capitalized terms used and not
defined herein shall have the meanings assigned such terms in the Offer to
Purchase and Schedule TO.

ITEMS 1 THROUGH 9 AND 11.

           Items 1 through 9 and 11 of the Schedule TO, which incorporate by
reference the information contained in the Offer to Purchase, are hereby amended
and supplemented as follows:

 
           The Offer expired at 5:30 pm on Wednesday, July 20, 2005. Based on a
preliminary count by the Depositary, there were tendered and not withdrawn
26,198,976 Shares as of 5:30 pm New York City time on July 20, 2005, and an
additional 839,738 Shares were guaranteed to be delivered within the next three
days. These Shares represent approximately 30.4% of the total outstanding Shares
and, together with the Santo Shares, represent approximately 97.9% of the total
outstanding Shares.

           The full text of the press release announcing the expiration of the
Offer is attached as Exhibit (a)(5)(I) hereto and is incorporated herein by
reference.



ITEM 12.   EXHIBITS



           Item 12 of the Schedule TO is hereby amended by adding thereto the
following:

(a)(5)(I) Text of Press Release issued by Novartis dated July 21, 2005.




                                    SIGNATURE

      After due 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.

Dated:  July 21, 2005

                                   NOVARTIS AG


                                    By: /s/ George Miller                
                                        --------------------------
                                        Name: George Miller  
                                        Title: Authorized Signatory


                                    By: /s/ Peter Rupprecht            
                                        --------------------------
                                        Name: Peter Rupprecht  
                                        Title: Authorized Signatory


                                    NOVARTIS CORPORATION


                                    By: /s/ Martin Henrich                  
                                        --------------------------
                                        Name: Martin Henrich
                                        Title: Executive Vice President


                                    ZODNAS ACQUISITION CORP.


                                    By: /s/ Wayne P. Merkelson            
                                        --------------------------
                                        Name: Wayne P. Merkelson  
                                        Title: Vice President




                                  EXHIBIT INDEX


*(a)(1)(A) Offer to Purchase, dated May 23, 2005.

*(a)(1)(B) Form of Letter of Transmittal.

*(a)(1)(C) Form of Notice of Guaranteed Delivery.

*(a)(1)(D) Form of Letter to Brokers, Dealers, Commercial Banks, Trust Companies
           and Other Nominees.

*(a)(1)(E) Form of Letter to Clients for use by Brokers, Dealers, Commercial
           Banks, Trust Companies and Other Nominees.

*(a)(1)(F) Guidelines for Certification of Taxpayer Identification Number (TIN)
           on Substitute Form W-9.

(a)(2)     Not applicable.

(a)(3)     Not applicable.

(a)(4)     Not applicable.

*(a)(5)(A) Text of Press Release issued by Novartis dated February 21, 2005,
           incorporated in this Schedule TO by reference to the Schedule TO
           filed by Novartis AG, Novartis US and Zodnas on February 22, 2005.

*(a)(5)(B) Form of Summary Advertisement published in The Wall Street Journal on
           May 23, 2005.

*(a)(5)(C) Text of Press Release issued by Novartis dated May 27, 2005.

*(a)(5)(D) Text of Press Release issued by Novartis dated June 7, 2005.

*(a)(5)(E) Text of Press Release issued by Novartis dated June 21, 2005.

*(a)(5)(F) Text of Press Release issued by Novartis dated July 5, 2005.

*(a)(5)(G) Text of Press Release issued by Novartis dated July 8, 2005.

*(a)(5)(H) Text of Press Release issued by Novartis dated July 19, 2005

(a)(5)(I)  Text of Press Release issued by Novartis dated July 21, 2005





*(a)(6)(A) Complaint titled Ellen Wiehl v. Eon Labs, Inc. et al., filed on
           February 22, 2005, in the Chancery Court of the State of Delaware,
           County of New Castle.

*(a)(6)(B) Complaint titled Paulena Partners LLC v. Eon Labs, Inc. et al., filed
           on February 22, 2005, in the Chancery Court of the State of Delaware,
           County of New Castle.

*(a)(6)(C) Complaint titled Robert Kemp, IRRA v. Eon Labs, Inc. et al., filed on
           February 22, 2005, in the Chancery Court of the State of Delaware,
           County of New Castle.

*(a)(6)(D) Complaint titled Peter J. Calcagno v. Eon Labs, Inc. et al., filed on
           February 23, 2005, in the Chancery Court of the State of Delaware,
           County of New Castle.

*(a)(6)(E) Complaint titled Christopher Pizzo v. Novartis AG et al., filed on
           February 23, 2005, in the Supreme Court of the State of New York,
           County of New York.

*(a)(6)(F) Complaint titled Erste Sparinvest Kapitalanlagegesellschaft MBH v.
           Eon Labs, Inc. et al., filed on March 1, 2005, in the Chancery Court
           of the State of Delaware, County of New Castle.

*(a)(6)(G) Complaint titled Merl Huntsinger v. Eon Labs, Inc. et al., filed on
           March 1, 2005, in the Chancery Court of the State of Delaware,
           County of New Castle.

*(a)(6)(H) Complaint titled Jason Hung v. Eon Labs, Inc. et al., filed on March
           3, 2005, in the Chancery Court of the State of Delaware, County of
           New Castle.

*(a)(6)(I) Consolidated Amended Complaint titled In re Eon Labs, Inc.
           Shareholders Litigation, filed on May 27, 2005, in the Chancery
           Court of the State of Delaware, County of New Castle.

*(a)(6)(J) Memorandum of Understanding dated as of July 8, 2005, by and among
           the parties to the actions filed in the Court of Chancery of the
           State of Delaware, County of Newcastle, titled IN RE EON LABS, INC.
           SHAREHOLDERS LITIGATION.

(b)        None.

*(d)(1)    Agreement and Plan of Merger, dated as of February 20, 2005, by and
           among Novartis US, Zodnas, Eon and, for purposes of Section 12
           thereof only, Novartis AG, incorporated in this Schedule TO by
           reference to Exhibit 2.2 to the Schedule 13D filed by Novartis US,
           Novartis AG and Zodnas on March 2, 2005.

*(d)(2)    Agreement for Purchase and Sale of Stock, dated as of February 20,
           2005, by and between Novartis US, Santo and, for purposes of Section
           10.12 thereof only, Novartis AG, incorporated in this Schedule TO by
           reference to Exhibit 2.1 to the Schedule 13D filed by Novartis US,
           Novartis AG and Zodnas on March 2, 2005.





*(d)(3)    Confidentiality Agreement, by and between Novartis US and Eon, dated
           as of February 11, 2005, incorporated in this Schedule TO by
           reference to Exhibit 2.3 to the Schedule 13D filed by Novartis US,
           Novartis AG and Zodnas on March 2, 2005.

(g)        None.

(h)        Not applicable.

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* Previously filed.