SEC FORM 4

SEC Form 4

FORM 4

UNITED STATES SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

STATEMENT OF CHANGES IN BENEFICIAL OWNERSHIP

Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934
or Section 30(h) of the Investment Company Act of 1940

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Check this box if no longer subject to Section 16. Form 4 or Form 5 obligations may continue. See Instruction 1(b).

1. Name and Address of Reporting Person^*

Casey Susan G

(Last)

(First)

(Middle)

406 BLACKWELL STREET

SUITE 240

(Street)

DURHAM

27701

(City)

(State)

(Zip)

2. Issuer Name and Ticker or Trading Symbol
SQUARE 1 FINANCIAL INC [ SQBK ]

5. Relationship of Reporting Person(s) to Issuer
(Check all applicable)

X	Director	10% Owner
	Officer (give title below)	Other (specify below)

3. Date of Earliest Transaction (Month/Day/Year)
10/06/2015

4. If Amendment, Date of Original Filed (Month/Day/Year)

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. Transaction Date (Month/Day/Year)	2A. Deemed Execution Date, if any (Month/Day/Year)	3. Transaction 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)
1. Title of Security (Instr. 3)	2. Transaction Date (Month/Day/Year)	2A. Deemed Execution Date, if any (Month/Day/Year)	Code	V	Amount	(A) or (D)	Price		6. Ownership Form: Direct (D) or Indirect (I) (Instr. 4)	7. Nature of Indirect Beneficial Ownership (Instr. 4)
Class A Common Stock	10/06/2015		D		253,636	D	⁽¹⁾⁽²⁾	0	D
Class A Common Stock	10/06/2015		D		13,500	D	⁽¹⁾⁽²⁾	0	I	By IRA

Table II - Derivative Securities Acquired, Disposed of, or Beneficially Owned (e.g., puts, calls, warrants, options, convertible securities)
1. Title of Derivative Security (Instr. 3)	2. Conversion or Exercise Price of Derivative Security	3. Transaction Date (Month/Day/Year)	3A. Deemed Execution Date, if any (Month/Day/Year)	4. Transaction 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 (Month/Day/Year)		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: Direct (D) or Indirect (I) (Instr. 4)	11. Nature of Indirect Beneficial Ownership (Instr. 4)
1. Title of Derivative Security (Instr. 3)	2. Conversion or Exercise Price of Derivative Security	3. Transaction Date (Month/Day/Year)	3A. Deemed Execution Date, if any (Month/Day/Year)	Code	V	(A)	(D)	Date Exercisable	Expiration Date	Title	Amount or Number of Shares	8. Price of Derivative Security (Instr. 5)		10. Ownership Form: Direct (D) or Indirect (I) (Instr. 4)	11. Nature of Indirect Beneficial Ownership (Instr. 4)
Restricted Stock Units	⁽¹⁾⁽²⁾	10/06/2015		D			721	⁽³⁾	⁽³⁾	Class A Common Stock	721	⁽¹⁾⁽²⁾	0	D

Explanation of Responses:

1. On October 6, 2015, pursuant to the Agreement and Plan of Merger, dated March 1, 2015, between PacWest Bancorp ("PacWest") and Square 1 Financial, Inc. ("Square 1"), Square 1 merged with and into PacWest, and each outstanding share of Square 1 common stock was converted into the right to receive 0.5997 of a share of PacWest common stock, with cash paid in lieu of fractional shares at a rate of $42.7827 per share (the "Average Closing Price"). At the effective time of the merger, each outstanding option to acquire shares of Square 1 common stock, whether vested or unvested, was cancelled and entitles the holder to receive an amount in cash equal to the product of (i) the total number of shares of Square 1 common stock subject to such option and

2. (ii) the excess, if any, of (A) the product of (1) the Average Closing Price and (2) 0.5997 over (B) the exercise price per share of Square 1 common stock underlying such option, less any applicable taxes to be withheld with respect to such payment. Each outstanding restricted stock unit issued under Square 1's stock plan, whether vested or unvested, was cancelled and entitles the holder to receive an amount in cash equal to the product of (i) the number of shares of Square 1 common stock subject to such restricted stock unit award and (ii) the product of (A) the Average Closing Price and (B) 0.5997. In connection with the merger, the reporting person has the right to receive 160,201 shares of PacWest common stock and $18,498.55 in cash, subject to any required tax withholding under applicable law. On October 6, 2015, the effective date of the merger, the closing price of PacWest common stock was $43.97 per share.

3. These restricted stock units were cancelled at the effective time of the merger and converted into the right to receive the consideration as described in notes (1) and (2) above.

	Leah Webb, Attorney-in-Fact	10/08/2015
	** 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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