Eagle Rock Energy Partners L P (EROC) DEFA14A Additional proxy soliciting materials

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

SCHEDULE 14A

Proxy Statement Pursuant to Section 14(a) of the Securities

Exchange Act of 1934 (Amendment No.  )

Filed by the Registrant þ

Filed by a Party other than the Registrant o

Check the appropriate box:

o Preliminary Proxy Statement

o Confidential, for Use of the Commission Only (as permitted by Rule 14a-6(e)(2))

o Definitive Proxy Statement

þ Definitive Additional Materials

o Soliciting Material Pursuant to §240.14a-12

Eagle Rock Energy Partners, L.P. 

 (Name of Registrant as Specified In Its Charter)

(Name of Person(s) Filing Proxy Statement, if other than the Registrant)

Payment of Filing Fee (Check the appropriate box):

þ	No fee required.
o	Fee computed on table below per Exchange Act Rules 14a-6(i)(1) and 0-11.
	(1)	Title of each class of securities to which transaction applies:
	(2)	Aggregate number of securities to which transaction applies:
	(3)	Per unit price or other underlying value of transaction computed pursuant to Exchange Act Rule 0-11 (set forth the amount on which the filing fee is calculated and state how it was determined):
	(4)	Proposed maximum aggregate value of transaction:
	(5)	Total fee paid:
o	Fee paid previously with preliminary materials.
o	Check box if any part of the fee is offset as provided by Exchange Act Rule 0-11(a)(2) and identify the filing for which the offsetting fee was paid previously. Identify the previous filing by registration statement number, or the Form or Schedule and the date of its filing.
	(1)	Amount Previously Paid:
	(2)	Form, Schedule or Registration Statement No.:
	(3)	Filing Party:
	(4)	Date Filed:

                                                                                                                                              0;         

May 6, 2010

Dear Limited Partner,

By now you should have received your annual report as well as your proxy statement and proxy card for Eagle Rock Energy Partners, L.P.’s Special Meeting to be held on May 14, 2010.  Our records show your common units have not yet been voted.

At this important meeting, our common unitholders will consider and vote on proposals intended to improve the Partnership’s liquidity position, simplify its structure and position it for future growth.  Our board of directors unanimously recommends that you vote “FOR” the proposals.  

These matters require the affirmative vote of a majority of our unaffiliated common unitholders.  To date, we have not received enough affirmative votes to meet the approval requirement, and we are therefore soliciting your vote again.  Please be aware that your broker cannot vote on your behalf with respect to the proposals.

Whether or not you plan to attend the Special Meeting, we urge you to vote as soon as possible.  If you do not cast a vote, it is equivalent to voting against the proposals.  Therefore, we urge you to vote today.

The fastest way to vote is to use the telephone or internet instructions on the enclosed proxy card.

If you have questions or if you need assistance voting, please contact Morrow & Co., LLC, our proxy solicitor, at 1-800-607-0088.

Thank you for your support of Eagle Rock and for taking the time to vote.

Sincerely,

/s/Joseph A. Mills

Joseph A. Mills

Chairman and Chief Executive Officer

P. O. Box 2968

Houston, TX  77252-2968

281-408-1200 OfficeWWW.EAGLEROCKENERGY.COM