ACHN Achison Inc (PK)

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 * G1 EXECUTION SERVICES, LLC	2. Issuer Name and Ticker or Trading Symbol ACHILLION PHARMACEUTICALS INC [ ACHN ]	5. Relationship of Reporting Person(s) to Issuer (Check all applicable) _____ Director                    __X__ 10% Owner _____ Officer (give title below)    _____ Other (specify below)
(Last)          (First)          (Middle) 175 W. JACKSON BLVD., SUITE 1700, 501 PLAZA 2	3. Date of Earliest Transaction (MM/DD/YYYY) 1/28/2020
(Street) CHICAGO, IL 60604 (City)        (State)        (Zip)	4. If Amendment, Date Original Filed (MM/DD/YYYY)	6. Individual or Joint/Group Filing (Check Applicable Line) ___ Form filed by One Reporting Person _ X _ 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	1/28/2020		J(1)		10917	D	$6.30 (1)	0	D (2)(4)
Common Stock	1/28/2020		J(1)		14115498	D	$6.30 (1)	0	D (3)(4)

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

Explanation of Responses:
(1)	Disposed of pursuant to an Agreement and Plan of Merger among Achillion Pharmaceuticals, Inc., Alexion Pharmaceuticals, Inc. and Beagle Merger Sub, Inc. In addition to the cash consideration of $6.30 per share, each shareholder will also receive one contingent value right ("CVR") per share. Each CVR represents the right to receive contingent cash payments of $1.00 upon the achievement of a certain clinical trial milestone with respect to ACH-5228 and $1.00 upon the achievement of a certain regulatory approval milestone with respect to ACH-4471.
(2)	These securities are directly owned by G1 Execution Services, LLC ("G1X").
(3)	These securities are directly owned by Susquehanna Securities, LLC ("SS").
(4)	G1X, Susquehanna Fundamental Investments, LLC ("SFNDI") and SS are affiliated entities under common ownership. G1X, SFNDI and SS each disclaim beneficial ownership of the reported securities except to the extent of their respective pecuniary interest therein, and this report shall not be deemed an admission that any of them are the beneficial owners of the securities for purposes of Section 16 of the Securities Exchange Act of 1934, as amended, or for any other purpose.

Reporting Owners
Reporting Owner Name / Address	Relationships
	Director	10% Owner	Officer	Other
G1 EXECUTION SERVICES, LLC 175 W. JACKSON BLVD., SUITE 1700 501 PLAZA 2 CHICAGO, IL 60604		X
SUSQUEHANNA FUNDAMENTAL INVESTMENTS, LLC 401 CITY AVENUE, SUITE 220 BALA CYNWYD, PA 19004		X
SUSQUEHANNA SECURITIES, LLC 401 CITY AVENUE, SUITE 220 BALA CYNWYD, PA 19004		X

Signatures
G1 Execution Services, LLC By: /s/ Brian Sopinsky Name: Brian Sopinsky Title: Secretary		1/30/2020
**Signature of Reporting Person		Date
Susquehanna Fundamental Investments, LLC By: /s/ Brian Sopinsky Name: Brian Sopinsky Title: Assistant Secretary		1/30/2020
**Signature of Reporting Person		Date
Susquehanna Securities, LLC By: /s/ Brian Sopinsky Name: Brian Sopinsky Title: Secretary		1/30/2020
**Signature of Reporting Person		Date