Exhibit 5.1

HCP, Inc.

3760 Kilroy Airport Way

Suite 300

Long Beach, California 90806

Re:          HCP, Inc., a Maryland corporation (the “Company”)

Ladies and Gentlemen:

We have acted as Maryland corporate counsel to the Company in connection with the registration of Three Hundred Fourteen Thousand Eight Hundred Thirty-Eight (314,838) shares (the “Shares”) of common stock of the Company, par value one dollar ($1.00) per share (“Common Stock”), to be issued to one or more holders (the “Selling Unit Holders”) of non-managing member units (the “Units”) in HCPI/Utah II, LLC, a Delaware limited liability company (the “LLC”), upon exchange of such Units, under the Securities Act of 1933, as amended (the “Act”), by the Company on Form S-3 (Registration No. 333-161721) filed with the Securities and Exchange Commission (the “Commission”) on or about September 4, 2009, as amended and supplemented (the “Registration Statement”).  You have requested our opinion with respect to the matters set forth below.

In our capacity as Maryland corporate counsel to the Company and for the purposes of this opinion, we have examined originals, or copies certified or otherwise identified to our satisfaction, of the following documents (collectively, the “Documents”):

(i)                                     the corporate charter of the Company (the “Charter”), consisting of Articles of Restatement filed with the State Department of Assessments and Taxation of Maryland (the “Department”) on August 2, 2004, Articles of Merger filed with the Department on November 30, 2004, Articles of Amendment filed with the Department on September 7, 2007 and Articles of Restatement filed with the Department on September 10, 2007;

Atlanta |  Baltimore |  Bethesda |  Denver |  Las Vegas |  Los Angeles |  New Jersey |  Philadelphia |  Phoenix |  Salt Lake City |  Washington, DC |  Wilmington

(ii)           the Fourth Amended and Restated Bylaws of the Company, dated as of September 20, 2006, as amended by Amendment No. 1 to Fourth Amended and Restated Bylaws of the Company dated as of October 25, 2007, Amendment No. 2 to Fourth Amended and Restated Bylaws of the Company dated as of October 29, 2009 and Amendment No. 3 to Fourth Amended and Restated Bylaws of the Company dated as of March 7, 2011 (collectively, the “Bylaws”);

(iii)          the Minutes of the Organizational Action of the Board of Directors of the Company, dated March 21, 1985 (the “Organizational Minutes”);

(iv)                              resolutions adopted by the Board of Directors of the Company on or as of July 19, 2001, January 28, 2005, October 25, 2008 and July 29, 2009 (the “Directors’ Resolutions”);

(v)                                 the Amended and Restated Limited Liability Company Agreement of the LLC, dated as of August 17, 2001 (the “Amended Agreement”), Amendment No. 1 to Amended and Restated Limited Liability Company Agreement of the LLC, dated as of October 30, 2001 (the “First Amendment”), Amendment No. 2 to Amended and Restated Limited Liability Company Agreement of the LLC, dated as of July 3, 2002 (the “Second Amendment”), Amendment No. 3 to Amended and Restated Limited Liability Company Agreement of the LLC, dated as of September 27, 2002 (the “Third Amendment”), Amendment No. 4 to Amended and Restated Limited Liability Company Agreement of the LLC, dated as of June 25, 2003 (the “Fourth Amendment”), Amendment No. 5 to Amended and Restated Limited Liability Company Agreement of the LLC, dated as of July 16, 2004 (the “Fifth Amendment”), Amendment No. 6 to Amended and Restated Limited Liability Company Agreement of the LLC and New Member Joinder Agreement, dated as of February 28, 2007 (the “Sixth Amendment”), and Amendment No. 7 to Amended and Restated Limited Liability Company Agreement of the LLC and New Member Joinder Agreement, dated as of July 26, 2010 (the “Seventh Amendment”, and together with the Amended Agreement, the First Amendment, the Second Amendment, the Third Amendment, the Fourth Amendment, the Fifth Amendment and the Sixth Amendment, the “LLC Agreement”);

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(vi)          a certificate of James W. Mercer, the Executive Vice President, General Counsel and Secretary of the Company, of even date herewith (the “Officer’s Certificate”), to the effect that, among other things, the Charter, the Bylaws, the Organizational Minutes, the Directors’ Resolutions and the LLC Agreement are true, correct and complete, have not been rescinded or modified and are in full force and effect on the date of the Officer’s Certificate;

(vii)         the Registration Statement and the related base prospectus dated September 9, 2009, and prospectus supplement relating to the sale of the Shares, each in the form filed or to be filed with the Commission pursuant to the Act;

(viii)        a status certificate of the Department, dated as of a recent date, to the effect that the Company is duly incorporated and existing under the laws of the State of Maryland; and

(ix)                              such other laws, records, documents, certificates, opinions and instruments as we have deemed necessary to render this opinion, subject to the limitations, assumptions and qualifications noted below.

In reaching the opinions set forth below, we have assumed the following:

(a)                                  each person executing any instrument, document or agreement on behalf of any party (other than the Company) is duly authorized to do so;

(b)                                 each natural person executing any instrument, document or agreement is legally competent to do so;

(c)                                  any of the Documents submitted to us as originals are authentic; the form and content of any Documents submitted to us as unexecuted drafts do not differ in any respect relevant to this opinion from the form and content of such documents as executed and delivered; any of the Documents submitted to us as certified or photostatic copies conform to the original documents; all signatures on all of the Documents are genuine; all public records reviewed or relied upon by us or on our behalf are true and complete; all statements and information contained in the Documents are true and complete; there has been no modification of, or amendment to, any of the Documents, and there has been no waiver of any provision of any of the Documents by action or omission of the parties or otherwise;

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(d)                                 prior to issuance of any of the Shares, the Board of Directors of the Company, or a properly appointed committee of the Board of Directors to which the Board of Directors has delegated the requisite power and authority, will adopt resolutions satisfying the requirements of Section 2-203 of the Maryland General Corporation Law with respect to the issuance of such Shares.

(e)                                  upon the issuance of any of the Shares subsequent to the date hereof, the total number of shares of Common Stock of the Company issued and outstanding on the date subsequent to the date hereof on which such Shares are issued will not exceed the total number of shares of Common Stock that the Company is authorized to issue under the Charter;

(f)                                    none of the Shares will be issued or transferred in violation of the provisions of Article V of the Charter relating to restrictions on ownership and transfer of stock or the provisions of Article V of the Charter relating to business combinations; and

(g)                                 none of the Shares will be issued and sold to an Interested Stockholder of the Company or an Affiliate thereof, all as defined in Subtitle 6 of Title 3 of the Maryland General Corporation Law (the “MGCL”), in violation of Section 3-602 of the MGCL.

Based on the foregoing, and subject to the assumptions and qualifications set forth herein, it is our opinion that, as of the date of this letter:

1.                                       The Company has been duly incorporated and is validly existing as a corporation in good standing under the laws of the State of Maryland.

2.                                       The Shares have been generally authorized for issuance, and if, as and when such Shares are issued and delivered by the Company to the Selling Unit Holders pursuant, in each case, to due authorization by the Board of Directors, or a properly appointed committee thereof to which the Board of Directors has delegated the requisite power and authority, in exchange for Units of the LLC, all in accordance with such authorization by the Board of Directors or committee thereof and upon the terms and conditions set forth in the LLC Agreement, such Shares will be duly authorized, validly issued, fully paid and non-assessable.

The foregoing opinion is limited to the substantive laws of the State of Maryland, and we do not express any opinion herein concerning any other law.  We express no opinion as to the applicability or effect of any federal or state securities laws, including the securities laws of the State of Maryland, or as to federal or state laws regarding fraudulent transfers.  To the extent that any matter as to which our opinion is expressed herein would be governed by any jurisdiction other than the State of Maryland, we do not express any opinion on such matter.

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This opinion letter is issued as of the date hereof and is necessarily limited to laws now in effect and facts and circumstances presently existing and brought to our attention.  We assume no obligation to supplement this opinion letter if any applicable laws change after the date hereof, or if we become aware of any facts or circumstances that now exist or that occur or arise in the future and may change the opinions expressed herein after the date hereof.

We consent to your filing this opinion as an exhibit to the Registration Statement and further consent to the filing of this opinion as an exhibit to the applications to securities commissioners for the various states of the United States for registration of the Shares.  We also consent to the identification of our firm as Maryland counsel to the Company in the section of the Registration Statement entitled “Validity of Securities”.  In giving this consent, we do not admit that we are within the category of persons whose consent is required by Section 7 of the Act.

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