Under the Securities Exchange Act of 1934
(Amendment No. 6)*

(Name of Issuer)

(Title of Class of Securities)

(CUSIP Number)

(Name, Address and Telephone Number of Person
Authorized to Receive Notices and Communications)

(Date of Event Which Requires Filing of this Statement)

If the filing person has previously filed a statement on Schedule 13G to report the acquisition that is the subject of this Schedule 13D, and is filing this schedule because of §§240.13d-1(e), 240.13d-1(f) or 240.13d-1(g), check the following box. o

Note: Schedules filed in paper format shall include a signed original and five copies of the schedule, including all exhibits. See §240.13d-7 for other parties to whom copies are to be sent.

* The remainder of this cover page shall be filled out for a reporting person's initial filing on this form with respect to the subject class of securities, and for any subsequent amendment containing information which would alter disclosures provided in a prior cover page.

The information required on the remainder of this cover page shall not be deemed to be "filed" for the purpose of Section 18 of the Securities Exchange Act of 1934 ("Act") or otherwise subject to the liabilities of that section of the Act but shall be subject to all other provisions of the Act (however, see the Notes).

(1)

(1)           Power is exercised through its sole general partner, Castle Creek Capital LLC

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(2)

(1)           Power is exercised through its sole general partner, Castle Creek Capital LLC

3

(1)                                  Power is exercised through its controlling members, Eggemeyer Advisory Corp and WJR Corp

(2)                                  Solely in its capacity as sole general partner of Castle Creek Capital Partners Fund IIa, LP and Castle Creek Capital Partners Fund IIb, LP

4

(1)                                  Power is exercised through its sole shareholder and President, John M. Eggemeyer, III

(2)                                  In its capacity as a controlling member of Castle Creek Capital LLC, the sole general partner of Castle Creek Capital Partners Fund IIa, LP and Castle Creek Capital Partners Fund IIb, LP

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(1)                                  Consists of 293,957 shares owned by Mr. Eggemeyer and 2,646 shares for which Mr. Eggemeyer is the sole trustee.

(2)                                  Consists of 2,529 shares for which power is exercised as President of Castle Creek Capital LLC and as sole shareholder of one of its controlling members. Power is shared with William J. Ruh as Executive Vice President of Castle Creek Capital LLC and as sole shareholder of one of its controlling members.

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(1)                                  Power is exercised through its sole shareholder and President, William J. Ruh

(2)                                  In its capacity as a controlling member of Castle Creek Capital LLC, the sole general partner of Castle Creek Capital Partners Fund IIa, LP and Castle Creek Capital Partners Fund IIb, LP

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(1)                                  Consists of 77,238 shares owned directly and 3,400 shares for which Mr. Ruh is the sole trustee

(2)                                  Consists of 2,529 shares for which power is exercised as Executive Vice President of Castle Creek Capital LLC and as sole shareholder of one of its controlling members. Power is shared with John M. Eggemeyer, III as President of Castle Creek Capital LLC and as sole shareholder of one of its controlling members

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This Amendment No. 6 (the “Amendment”) amends and supplements the Schedule 13D jointly filed by Castle Creek Capital Partners Fund I, LP; Castle Creek Capital Partners Fund IIa, LP; Castle Creek Capital Partners Fund IIb, LP; Castle Creek Capital LLC; Eggemeyer Advisory Corp; John M. Eggemeyer, III; WJR Corp.; and William J. Ruh on December 11, 2001, as previously amended and supplemented by Amendment No. 1 filed on February 13, 2002; Amendment No. 2, filed on July 26, 2002; Amendment No. 3 filed on August 1, 2002 (as amended and supplemented, the “Schedule 13D”); Amendment No. 4 filed on August 10, 2005, and Amendment No 5filed on December 1, 2005 with respect to the common stock, with no par value, (the “Common Stock”) of PacWest Bancorp, a California corporation with its principal executive offices at 401 West “A” Street, San Diego,, CA 92101 (the “Issuer”). All capitalized terms used in this Amendment that are not otherwise defined herein have the meanings ascribed to such terms in the Schedule 13D.

Item 3 of this statement on Form 13D is hereby amended by adding the following:

Item 4. Purpose of theTransaction

On October 29, 2009, Castle Creek Capital Partners Fund IIa, LP, distributed 971,729 shares of the Issuer to the partners of Fund IIa and Castle Creek Capital Partners Fund IIb, LP distributed 410,457 shares of the Issuer to the partners of Fund IIb .  There are 77 investors in Fund IIa and 74 investors in Fund IIb.

Item 5 of this statement on Form 13D is hereby amended and restated in its entirety as follows:

Item 5. Interest in Securities of the Issuer

(a)(i) For each Reporting Person, as of October 30, 2009, the aggregate number of shares of Common Stock owned and the corresponding percentage of the total outstanding commons Stock of the Issuer is as follows (all percentages are based on 32,210,308 shares of Common Stock outstanding):

John M. Eggemeyer III

John M. Eggemeyer beneficially owns 299,132 shares of Common Stock which equals approximately 0.93% of the Issuers’ outstanding Common Stock. Mr. Eggemeyer’s sole beneficial ownership includes 293,957 shares owned directly and 2,646 shares for which he is the sole trustee. Mr. Eggemeyer’s shared beneficial ownership of 2,529 shares includes 2,529 shares beneficially owned as sole stockholder of Eggemeyer Advisory Corp

Eggemeyer Advisory Corp.

Eggemeyer Advisory Corp., as a controlling member of Castle Creek Capital LLC, beneficially owns 2,529 shares of Common Stock which equal approximately 0.01% of the Issuer’s outstanding Common Stock.

William J. Ruh

William J. Ruh beneficially owns 83,167 shares of Common Stock which equals approximately 0.26% of the Issuers’ outstanding Common Stock. Mr. Ruh’s sole beneficial ownership includes 77,238 shares owned directly, and 3,400 shares for which he is the sole trustee.. Mr. Ruh’s shared beneficial ownership of 2,529 shares includes 2,529 shares beneficially owned as sole stockholder of WJR Corp.

WJR Corp

WJR Corp., as a controlling member of Castle Creek Capital LLC, beneficially owns 2,529 shares of Common Stock which equal approximately 0.01% of the Issuer’s outstanding Common Stock

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Castle Creek Capital LLC

Castle Creek Capital LLC as the sole general partnes of Fund II, and Fund IIb beneficially owns 2,529 shares of Common Stock which equals approximately 0.01% of the Issuers outstanding Common Stock.

Castle Creek Capital Partners Fund IIa, LP

Castle Creek Capital Partner Fund IIa, LP beneficially owns 1,776 shares of Common Stock which equals approximately 0.01% of the Issuer’s outstanding Common Stock.

Castle Creek Capital Partners Fund IIb, LP

Castle Creek Capital Partner Fund IIb, LP beneficially owns 753 shares of Common Stock which equals approximately 0.00% of the Issuer’s outstanding Common Stock.

(b) For each person named in response to paragraph (a), indicate the number of shares as to which there is sole power to vote or to direct the vote, shared power to vote or direct the vote, sole or share power to dispose or to direct the disposition>

(c) The following is a list of the transactions in the shares of the Common Stock effected by the Reporting Persons during the past 60 days:

John M. Eggemeyer received a total of 15,930 shares in distributions from Castle Creek Capital Partners Fund IIa, LP and Castle Creek Capital Partners Fund IIb, LP on October 29, 2009.

William J. Ruh received 10,620 shares in a distribution from Castle Creek Capital Partners Fund IIb, LP on October 29, 2009.

Item 7. Material to be Filed as Exhibits

Exhibit 1 Agreement of Joint Filing

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Signature

After reasonable 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.

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