Statement of Changes in Beneficial Ownership (4)

FORM 4 [ X ] Check this box if no longer subject to Section 16. Form 4 or Form 5 obligations may continue. See Instruction 1(b).	UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 STATEMENT OF CHANGES IN BENEFICIAL OWNERSHIP OF SECURITIES	OMB APPROVAL OMB Number: 3235-0287 Estimated average burden hours per response... 0.5
	Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934 or Section 30(h) of the Investment Company Act of 1940

1. Name and Address of Reporting Person * Schaum Meredith	2. Issuer Name and Ticker or Trading Symbol OPTIMER PHARMACEUTICALS INC [ OPTR ]	5. Relationship of Reporting Person(s) to Issuer (Check all applicable) _____ Director                      _____ 10% Owner __ X __ Officer (give title below)      _____ Other (specify below) Gen Counsel and Chief Comp Off
(Last)          (First)          (Middle) 101 HUDSON STREET, SUITE 3501	3. Date of Earliest Transaction (MM/DD/YYYY) 10/24/2013
(Street) JERSEY CITY, NJ 07302 (City)        (State)        (Zip)	4. If Amendment, Date Original Filed (MM/DD/YYYY)	6. Individual or Joint/Group Filing (Check Applicable Line) _ X _ Form filed by One Reporting Person ___ Form filed by More than One Reporting Person

Table I - Non-Derivative Securities Acquired, Disposed of, or Beneficially Owned
1.Title of Security (Instr. 3)	2. Trans. Date	2A. Deemed Execution Date, if any	3. Trans. Code (Instr. 8)		4. Securities Acquired (A) or Disposed of (D) (Instr. 3, 4 and 5)			5. Amount of Securities Beneficially Owned Following Reported Transaction(s) (Instr. 3 and 4)	6. Ownership Form: Direct (D) or Indirect (I) (Instr. 4)	7. Nature of Indirect Beneficial Ownership (Instr. 4)
			Code	V	Amount	(A) or (D)	Price
Common stock	10/24/2013		D		2937   (1)	D	$10.75   (2)	0	D

Table II - Derivative Securities Beneficially Owned ( e.g. , puts, calls, warrants, options, convertible securities)
1. Title of Derivate Security (Instr. 3)	2. Conversion or Exercise Price of Derivative Security	3. Trans. Date	3A. Deemed Execution Date, if any	4. Trans. Code (Instr. 8)		5. Number of Derivative Securities Acquired (A) or Disposed of (D) (Instr. 3, 4 and 5)		6. Date Exercisable and Expiration Date		7. Title and Amount of Securities Underlying Derivative Security (Instr. 3 and 4)		8. Price of Derivative Security (Instr. 5)	9. Number of derivative Securities Beneficially Owned Following Reported Transaction(s) (Instr. 4)	10. Ownership Form of Derivative Security: Direct (D) or Indirect (I) (Instr. 4)	11. Nature of Indirect Beneficial Ownership (Instr. 4)
				Code	V	(A)	(D)	Date Exercisable	Expiration Date	Title	Amount or Number of Shares
Stock option (right to buy)	$10.72	10/24/2013		D			30000	(3)	2/26/2023	Common stock	30000	$2.06	0	D

Explanation of Responses:
( 1)	Includes 1,148 shares acquired under the Optimer Pharmaceuticals, Inc. ("Optimer") employee stock purchase plan on October 22, 2013.
( 2)	Pursuant to the Agreement and Plan of Merger, dated as of July 30, 2013 (the "Merger Agreement"), among Optimer, Cubist Pharmaceuticals, Inc. ("Cubist"), and PDRS Corporation, shares were converted into the right to receive per share consideration of: (i) $10.75 cash and (ii) one contingent value right issued by Cubist in accordance with the Contingent Value Rights Agreement, dated as of October 24, 2013, between Cubist and American Stock Transfer & Trust Company, LLC (together, the "Per Share Merger Consideration").
( 3)	Pursuant to the terms of the Merger Agreement, each option was fully vested and converted into the right to receive a cash payment equal to the excess, if any, of $12.78 (the last reported sale price of a share of Optimer common stock on The NASDAQ Global Select Market on October 23, 2013) over such option's per share exercise price.

Reporting Owners
Reporting Owner Name / Address	Relationships
	Director	10% Owner	Officer	Other
Schaum Meredith 101 HUDSON STREET SUITE 3501 JERSEY CITY, NJ 07302			Gen Counsel and Chief Comp Off

Signatures
Meredith Schaum		10/28/2013
** Signature of Reporting Person		Date

Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly.
*	If the form is filed by more than one reporting person, see Instruction 4(b)(v).
**	Intentional misstatements or omissions of facts constitute Federal Criminal Violations. See 18 U.S.C. 1001 and 15 U.S.C. 78ff(a).
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