UNITED STATES SECURITIES AND EXCHANGE COMMISSION

                             WASHINGTON, D.C. 20549

                                   FORM 12B-25

                           NOTIFICATION OF LATE FILING

(Check one):    /  / Form 10-K   /  /Form 20-F    /  /Form 11-K  /X/Form 10-Q
               /  /Form N-SAR    /  /Form N-CSR

                            For Period Ended: 3/31/06

/  /Transition Report on Form 10-K
/  /Transition Report on Form 20-F
/  /Transition Report on Form 11-K
/  /Transition Report on Form 10-Q
/  /Transition Report on Form N-SAR For the Transition Period Ended:
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  Read instruction (on back page) Before Preparing Form. Please Print or Type.
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NOTHING IN THIS FORM SHALL BE CONSTRUED TO IMPLY THAT THE COMMISSION HAS
VERIFIED ANY INFORMATION CONTAINED HEREIN.

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If the notification relates to a portion of the filing checked above, identify
the Item(s) to which the notification relates:

NOT APPLICABLE
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PART I -- REGISTRANT INFORMATION

LIGAND PHARMACEUTICALS INCORPORATED
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Full Name of Registrant

NOT APPLICABLE
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Former Name if Applicable

10275 SCIENCE CENTER DRIVE
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Address of Principal Executive Office (Street and Number)

SAN DIEGO, CA  92121
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City, State and Zip Code





PART II - RULES 12B-25(B) AND (C)

     If the subject report could not be filed without unreasonable effort or
expense and the registrant seeks relief pursuant to Rule 12b-25(b), the
following should be completed. (Check box if appropriate)

          (a)  The reason described in reasonable detail in Part III of this
               form could not be eliminated without unreasonable effort or
               expense

  /x/          (b) The subject annual report, semi-annual report, transition
               report on Form 10-K, Form 20-F, Form 11-K, Form N-SAR or Form
               N-CSR, or portion thereof, will be filed on or before the
               fifteenth calendar day following the prescribed due date; or the
               subject quarterly report or transition report on Form 10-Q, or
               portion thereof, will be filed on or before the fifth calendar
               day following the prescribed due date; and

          (c)  The accountant's statement or other exhibit required by Rule
               12b-25(c) has been attached if applicable.

PART III - NARRATIVE

State below in reasonable detail why Forms 10-K, 20-F, 11-K, 10-Q, N-SAR, N-CSR,
or the transition report or portion thereof, could not be filed within the
prescribed time period.

The quarterly report on Form 10-Q of Ligand Pharmaceuticals Incorporated (the
"Company") for the period ended March 31, 2006 could not be filed with the
Securities and Exchange Commission on a timely basis due to the following
reasons:

     The Company requires additional time to complete accounting adjustments
     relating to the termination of the Organon Co-Promotion Agreement and
     implementation of FAS 123(R) - "Share Based Payment."

PART IV - OTHER INFORMATION

1.   Name and telephone number of person to contact in regard to this
     notification


                                                  
Warner R. Broaddus              (858)                   550-7500
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(Name) (Area Code) (Telephone Number)



2.   Have all other periodic reports required under Section 13 or 15(d) of the
     Securities Exchange Act of 1934 or Section 30 of the Investment Company Act
     of 1940 during the preceding 12 months or for such shorter period that the
     registrant was required to file such report(s) been filed? If answer is no,
     identify report(s). Yes /x / No/ /






3.   Is it anticipated that any significant change in results of operations from
     the corresponding period for the last fiscal year will be reflected by the
     earnings statements to be included in the subject report or portion
     thereof? Yes /x/ No/ /

If so, attach an explanation of the anticipated change, both narratively and
quantitatively, and, if appropriate, state the reasons why a reasonable estimate
of the results cannot be made.

     Until the adjustments referenced above are made and preparation of the
     financial statements is completed by the Company and reviewed by its
     independent accounting firm, we cannot estimate the changes in results of
     operations.


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                       LIGAND PHARMACEUTICALS INCORPORATED
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                  (Name of Registrant as Specified in Charter)

has caused this notification to be signed on its behalf by the undersigned
hereunto duly authorized.



Date   March 10, 2006
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By    /S/ WARNER R. BROADDUS
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      Warner R. Broaddus
      General Counsel, Vice President & Secretary