American Assets Trust (AAT) 424B7 Prospectus with selling stockholder info

Filed Pursuant to Rule 424(b)(7)

Registration No. 333-252097

CALCULATION OF REGISTRATION FEE

Title Of Securities Being Registered	Number of Shares to be Registered(1)	Proposed Maximum Offering Price Per Share(2)	Proposed Maximum Aggregate Offering Price(3)	Amount Of Registration Fee(4)
Common Stock, par value $.01 per share	22,178,095(1)	$27.95(2)	$619,877,755.25(3)	$—(4)

(1) Including an indeterminate number of shares that may be issued by American Assets Trust, Inc. with respect to such shares of common stock by way of a stock dividend, stock split or in connection with a stock combination, recapitalization, merger, consolidation or otherwise.

(2) Based upon the average of the high and low prices of our common stock reported on the New York Stock Exchange on January 12, 2021, pursuant to Rule 457(c) of the Securities Act of 1933, as amended.

(3) Estimated solely for the purpose of calculating the registration fee pursuant to Rule 457 of the Securities Act.

(4) Pursuant to Rule 415(a)(6) under the Securities Act, the registrant is carrying forward to this prospectus supplement (and the registration statement (No. 333-252097) of the registrant filed on January 14, 2021 (the “2021 Registration Statement”), of which this prospectus supplement forms a part) 22,178,095 shares of common stock that were previously registered on the registration statement (No. 333-201909) of the registrant, which was filed with the Securities and Exchange Commission (the “SEC”) on February 6, 2015 (the “2015 Registration Statement”) and automatically became effective upon filing, and registration fees of $63,266, $954 and $14,793 that were previously paid on February 6, 2015, March 26, 2015 and April 28, 2015, respectively, in connection with the registrant’s filing of the 2015 Registration Statement. Such securities and registration fees were previously carried forward to a prospectus supplement dated February 7, 2018 (and the registration statement (No. 333-222876) of the registrant filed on February 5, 2018, of which it formed a part (the “2018 Registration Statement”). The 2018 Registration Statement terminated effective upon the filing of the 2021 Registration Statement on January 14, 2021.

PROSPECTUS SUPPLEMENT

(To Prospectus dated January 14, 2021)

American Assets Trust, Inc.

22,178,095 Shares of Common Stock

This prospectus supplement supplements our prospectus dated January 14, 2021 and relates to (1) the possible issuance of shares of common stock of American Assets Trust, Inc., a Maryland corporation (“we” or “our”), to the holders of common units representing common limited partnership interests in American Assets Trust, L.P., our operating partnership, and the possible resale of shares of common stock by such holders from one or more sellers in the open market, (2) the possible resale by Insurance Company of the West of 400,000 shares of our common stock issued in a private placement on September 12, 2014 and (3) the possible resale by Explorer Insurance Company of 200,000 shares of our common stock issued in a private placement on March 9, 2015. Holders of common limited partnership units identified in this prospectus supplement were issued such units in a private placement transaction and are entitled to tender their common units to our operating partnership for cash redemption. We may elect to exchange such tendered units for shares of our common stock on a one-for-one basis. We will not receive any of the proceeds from the issuance of the common stock to the holder or from the resale of the shares by the holders.

You should read this prospectus supplement in conjunction with the prospectus. This prospectus supplement is not complete without, and may not be delivered or used except in conjunction with, the prospectus, including any amendments or supplements to it. This prospectus supplement is qualified by reference to the prospectus, except to the extent that the information provided by this prospectus supplement supplements information contained in the prospectus.

Investing in our common stock involves risks. See “Risk Factors” beginning on page 5 of the prospectus as well as the risk factors relating to our business that are incorporated by reference in the prospectus.

Neither the Securities and Exchange Commission nor any state securities commission has approved or disapproved of these securities or determined if this prospectus supplement or the accompanying prospectus is truthful or complete. Any representation to the contrary is a criminal offense.

The date of this Prospectus Supplement is January 14, 2021.

The section entitled “Selling Security holders” in the prospectus is hereby supplemented as follows:

SELLING STOCKHOLDERS

The “selling stockholders” are the people or entities who may sell shares of our common stock registered pursuant to this prospectus supplement, and the accompanying prospectus. Such selling stockholders may currently hold shares of our common stock registered pursuant to this prospectus supplement or may receive shares of our common stock registered pursuant to this prospectus supplement upon exchange of common units. The following table provides the names of the selling stockholders, the number of shares of our common stock currently held by such selling shareholders prior to any exchange by them of common units, the maximum number of shares of our common stock currently issuable to such selling stockholders in such exchange and the aggregate number of shares of our common stock that will be owned by such selling stockholders after the exchange. Since the selling stockholders may sell all, some or none of their shares, we cannot estimate the aggregate number of shares that the selling stockholders will offer pursuant to this prospectus supplement or that the selling stockholders will own upon completion of the offering to which this prospectus supplement relates. The following table does not take into effect any restrictions on ownership or transfer as described in “Restrictions on Ownership and Transfer” in the accompanying prospectus.

The selling stockholders named below and their permitted transferees, pledgees, orderees or other successors may from time to time offer the shares of our common stock offered by this prospectus supplement:

Name of Beneficial Owner (1)	Common Shares Owned Prior to the Exchange		Common Units Owned Prior to the Exchange		Maximum Number of Common Shares Issuable in the Exchange		Common Shares Owned Following the Exchange (2)					Maximum Number of Shares to be Resold		Common Shares Owned After Resale (3)
							Number		%					Number		%
Ernest Rady Trust U/D/T March 10, 1983 (4)		6,258,628		9,720,409		9,720,409		15,979,037		20.95	%		14,399,145		1,579,892		2.62	%
American Assets, Inc. (5)		1,673,449		5,107,577		5,107,577		6,781,026		10.11	%		5,107,577		1,673,449		2.78	%
Insurance Company of the West (6)		1,255,336		0		0		1,255,336		2.04	%		400,000		855,336		1.42	%
Rady Foundation dated August 5, 2020 (7)		719,341		0		0		719,341		1.18	%		717,341		2,000		*
The Stuart C. Gildred (Trust A) UTA Dated 8/18/76 (8)		0		531,973		531,973		531,973		*			531,973		0		*
Parma Family Limited Partnership (9)		27,107		243,920		243,920		271,027		*			243,920		27,107		*
Explorer Insurance Company (10)		200,000		0		0		200,000		*			200,000		0		*
Donald R. Rady Trust DTD 11/26/92 (11)		0		167,374		167,374		167,374		*			167,374		0		*
Robert & Katherine Barton Living Trust UTA 4/21/07 (12)		90,807		0		0		90,807		*			481		90,326		*
Margo S. Rady Trust DTD 11/26/92 (13)		0		91,252		91,252		91,252		*			91,252		0		*
Margo S. Rady Trust UTA Dated 7/1/2005 (14)		0		76,098		76,098		76,098		*			76,098		0		*

Name of Beneficial Owner (1)	Common Shares Owned Prior to the Exchange		Common Units Owned Prior to the Exchange		Maximum Number of Common Shares Issuable in the Exchange		Common Shares Owned Following the Exchange (2)				Maximum Number of Shares to be Resold		Common Shares Owned After Resale (3)
							Number		%				Number		%
Grandtodd, LLC (15)		0		76,068		76,068		76,068		*		76,068		0		*
Firestone Investment LP (16)		0		63,627		63,627		63,627		*		63,627		0		*
Elkus Enterprises (15)		0		50,737		50,737		50,737		*		50,737		0		*
Philip L. Elkus Trust UDT 9/9/74 (17)		0		13,697		13,697		13,697		*		13,697		0		*
Parma Family Trust DTD 7/31/73 (9)		0		7,130		7,130		7,130		*		7,130		0		*
ICW Group Holdings Inc. (18)		0		2,004		2,004		2,004		*		2,004		0		*
Other selling stockholders as a group (19)		0		29,671		29,671		29,671		*		29,671		0		*
Total		10,224,668		16,181,537		16,181,537		26,406,205				22,178,095		4,201,003

* Less than 1.0 percent.

(1) Except for Insurance Company of the West and Explorer Insurance Company, the selling stockholders listed below hold shares of our common stock and/or common units in our operating partnership received in connection with private placements that we entered into in connection with our initial public offering.

(2) Assumes that we exchange the common units of the selling stockholders for shares of our common stock, regardless of whether such common units are currently exchangeable. The percentage ownership is determined for each selling stockholder by taking into account the issuance and sale of shares of our common stock of only such selling stockholder. Also assumes that no transactions with respect to our common stock or common units occur other than the exchange. Based on a total of 60,282,929 shares of our common stock outstanding as of October 30, 2020.

(3) Assumes that the selling stockholders sell all of their shares of our common stock offered pursuant to this prospectus supplement. The percentage ownership is determined for each selling stockholder by taking into account the issuance and sale of shares of our common stock of only such selling stockholder. Based on a total of 60,282,929 shares of our common stock outstanding as of October 30, 2020.

(4) Ernest Rady is the trustee of Ernest Rady Trust U/D/T March 10, 1983 and has the voting and dispositive power over its shares of common stock and common units. Mr. Rady is our Chairman, President and Chief Executive Officer and owns more than 10% of our outstanding common stock.

(5) Mr. Rady is the president of American Assets, Inc. and has the voting and dispositive power over its shares of common stock and common units. Mr. Rady is our Chairman, President and Chief Executive Officer and owns more than 10% of our outstanding common stock.

(6) Mr. Rady is chairman of Insurance Company of the West and has the voting and dispositive power of its shares of common stock. Mr. Rady is our Chairman, President and Chief Executive Officer and owns more than 10% of our outstanding common stock..

(7) Mr. Rady is the trustee of the Rady Foundation dated August 8, 2020 and has the voting and dispositive power over its shares of common stock. Mr. Rady is our Chairman, President and Chief Executive Officer and owns more than 10% of our outstanding common stock.

(8) Lynn R. Gildred is the trustee of The Stuart C. Gildred (Trust A) UTA Dated 8/18/76 and has voting and dispositive power over its common units.

(9) Leon W. Parma is the managing general partner of Parma Family Limited Partnership and has the voting and dispositive power over its shares of common stock and common units. Leon W. Parma has voting and dispositive power over its common units.

(10) Mr. Rady is the chairman of Explorer Insurance Company. and has the voting and dispositive power over its shares of common stock and common units. Mr. Rady is our Chairman, President and Chief Executive Officer and owns more than 10% of our outstanding common stock.

(11) Donald R. Rady is the trustee of the Donald R. Rady Trust DTD 11/26/92 and has the voting and dispositive power over its common units.

(12) Robert F. Barton is the trustee of the Robert & Katherine Barton Living Trust dated 4/21/07 and has voting and dispositive power over its shares of common stock. Mr. Barton is our Executive Vice President and Chief Financial Officer.

(13) Margo S. Rady is the trustee of the Margo S. Rady Trust DTD 11/26/92 and has the voting and dispositive power over its common units.

(14) Bernard Feldman is the trustee of the Margo S. Rady Trust UTA Dated 7/1/2005, and has the voting and dispositive power over their common units.

(15) David R. Elkus has the voting and dispositive power over the common units owned by each of (a) Grandtodd, LLC and (b) Elkus Enterprises.

(16) Michael Leibowitz and Karen Mallari are the Managers of Firestone Asset Management, LLC, which is the General Partner of Firestone Investments, L.P. and hold all voting and dispositive powers over its common units.

(17) Philip L. Elkus is the trustee of the Philip L. Elkus Trust UDT 9/9/74 and has the voting and dispositive power over its common units.

(18) Mr. Rady is the chairman of ICW Group Holdings, Inc. and has the voting and dispositive power over its shares of common stock and common units. Mr. Rady is our Chairman, President and Chief Executive Officer and owns more than 10% of our outstanding common stock.

(19) Amount includes the aggregate holdings of unrelated selling stockholders that represent less than 1% of our 60,282,929 shares of common stock outstanding as of October 30, 2020. No selling stockholder included in this group has held any position or office with us or had a material relationship with us in the past three years.

PROSPECTUS

Guarantees

AMERICAN ASSETS TRUST, L.P.

Debt Securities

We may offer and sell the securities identified above from time to time in one or more offerings. This prospectus provides you with a general description of the securities.

Each time we offer and sell securities, we will provide a supplement to this prospectus that contains specific information about the offering, as well as the amounts, prices and terms of the securities. The supplement may also add, update or change information contained in this prospectus with respect to that offering. You should carefully read this prospectus and the applicable prospectus supplement before you invest in any of our securities.

American Assets Trust, L.P. may offer and sell the securities described in this prospectus and any prospectus supplement to or through one or more underwriters, dealers and agents, or directly to purchasers, or through a combination of these methods. If any underwriters, dealers or agents are involved in the sale of any of the securities, their names and any applicable purchase price, fee, commission or discount arrangement between or among them will be set forth, or will be calculable from the information set forth, in the applicable prospectus supplement. See the sections of this prospectus entitled “About this Prospectus” and “Plan of Distribution” for more information. No securities may be sold without delivery of this prospectus and the applicable prospectus supplement describing the method and terms of the offering of such securities.

INVESTING IN OUR SECURITIES INVOLVES RISKS. SEE THE “RISK FACTORS” ON PAGE 5 OF THIS PROSPECTUS AND ANY SIMILAR SECTION CONTAINED IN THE APPLICABLE PROSPECTUS SUPPLEMENT CONCERNING FACTORS YOU SHOULD CONSIDER BEFORE INVESTING IN OUR SECURITIES.

American Assets Trust, Inc.’s common stock is listed on the New York Stock Exchange under the symbol “AAT.” On January 13, 2021, the last reported sale price of American Assets Trust, Inc.’s common stock on the New York Stock Exchange was $28.47 per share.

Neither the Securities and Exchange Commission nor any state securities commission has approved or disapproved of these securities or passed upon the adequacy or accuracy of this prospectus. Any representation to the contrary is a criminal offense.

The date of this prospectus is January 14, 2021.

TABLE OF CONTENTS

ABOUT THIS PROSPECTUS	1
WHERE YOU CAN FIND MORE INFORMATION; INCORPORATION BY REFERENCE	2
THE COMPANY	4
RISK FACTORS	5
GUARANTOR DISCLOSURES	6
USE OF PROCEEDS	7
DESCRIPTION OF DEBT SECURITIES AND RELATED GUARANTEES	8
DESCRIPTION OF THE PARTNERSHIP AGREEMENT OF AMERICAN ASSETS TRUST, L.P.	20
MATERIAL PROVISIONS OF MARYLAND LAW AND OF OUR CHARTER AND BYLAWS	28
FEDERAL INCOME TAX CONSIDERATIONS	34
PLAN OF DISTRIBUTION	35
LEGAL MATTERS	36
EXPERTS	36

ABOUT THIS PROSPECTUS

This prospectus is part of a registration statement that we filed with the U.S. Securities and Exchange Commission, or the SEC, as a “well-known seasoned issuer” as defined in Rule 405 under the Securities Act of 1933, as amended, or the Securities Act, using a “shelf” registration process. By using a shelf registration statement, we may sell securities (including guarantees of debt securities sold by our operating partnership) from time to time and in one or more offerings as described in this prospectus. Each time that we offer and sell securities, we will provide a prospectus supplement to this prospectus that contains specific information about the securities being offered and sold and the specific terms of that offering. The prospectus supplement may also add, update or change information contained in this prospectus with respect to that offering. If there is any inconsistency between the information in this prospectus and the applicable prospectus supplement, you should rely on the prospectus supplement. Before purchasing any securities, you should carefully read both this prospectus and the applicable prospectus supplement, together with the additional information described under the heading “Where You Can Find More Information; Incorporation by Reference.”

We have not authorized any other person to provide you with different information. If anyone provides you with different or inconsistent information, you should not rely on it. We will not make an offer to sell these securities in any jurisdiction where the offer or sale is not permitted. You should assume that the information appearing in this prospectus and the applicable prospectus supplement to this prospectus is accurate as of the date on its respective cover, and that any information incorporated by reference is accurate only as of the date of the document incorporated by reference, unless we indicate otherwise. Our business, financial condition, results of operations and prospects may have changed since those dates.

References in this prospectus to the “Company” or the “guarantor” refer to American Assets Trust, Inc., a Maryland corporation. When we refer to “we,” “our,” “us” and “our company” in this prospectus, we mean the Company, American Assets Trust, L.P., and any of our other subsidiaries, unless otherwise specified. When we refer to “you,” we mean the holders of the applicable class or series of securities. American Assets Trust, L.P. is a Maryland limited partnership of which we are the sole general partner and to which we refer in this prospectus as our operating partnership.

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WHERE YOU CAN FIND MORE INFORMATION; INCORPORATION BY REFERENCE

Available Information

The Company and the operating partnership file reports, proxy statements and other information with the SEC. The SEC maintains a web site that contains reports, proxy and information statements and other information about issuers, such as us, who file electronically with the SEC. The address of that website is http://www.sec.gov.

Our web site address is www.americanassetstrust.com. The information on our web site, however, is not, and should not be deemed to be, a part of this prospectus.

This prospectus and any prospectus supplement are part of a registration statement that we filed with the SEC and do not contain all of the information in the registration statement. The full registration statement may be obtained from the SEC or us, as provided below. Forms of the indenture and other documents establishing the terms of the offered securities are or may be filed as exhibits to the registration statement. Statements in this prospectus or any prospectus supplement about these documents are summaries and each statement is qualified in all respects by reference to the document to which it refers. You should refer to the actual documents for a more complete description of the relevant matters. You may inspect a copy of the registration statement through the SEC’s website, as provided above.

Incorporation by Reference

The SEC’s rules allow us to “incorporate by reference” information into this prospectus, which means that we can disclose important information to you by referring you to another document filed separately with the SEC. The information incorporated by reference is deemed to be part of this prospectus, and subsequent information that we file with the SEC will automatically update and supersede that information. Any statement contained in a previously filed document incorporated by reference will be deemed to be modified or superseded for purposes of this prospectus to the extent that a statement contained in this prospectus modifies or replaces that statement.

We incorporate by reference our documents listed below and any future filings made by American Assets Trust, Inc. and American Assets Trust, L.P. with the SEC under Sections 13(a), 13(c), 14 or 15(d) of the Securities Exchange Act of 1934, as amended, which we refer to as the “Exchange Act” in this prospectus, between the date of this prospectus and the termination of the offering of the securities described in this prospectus. We are not, however, incorporating by reference any documents or portions thereof, whether specifically listed below or filed in the future, that are not deemed “filed” with the SEC, including our Compensation Committee report and performance graph or any information furnished pursuant to Items 2.02 or 7.01 of Form 8-K or related exhibits furnished pursuant to Item 9.01 of Form 8-K.

This prospectus and any accompanying prospectus supplement incorporate by reference the documents set forth below that have previously been filed with the SEC:

• our Annual Report on Form 10-K for the year ended December 31, 2019, filed with the SEC on February 14, 2020.

• our Quarterly Reports on Form 10-Q for the quarters ended March 31, 2020, June 30, 2020 and September 30, 2020, filed with the SEC on May  1, 2020, July 31, 2020 and October 30, 2020.

• our Definitive Proxy Statement on Schedule 14A, filed with the SEC on April 10, 2020.

• our Current Reports on Form 8-K filed with the SEC on June 9, 2020, January  8, 2021 and January 14, 2021.

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All reports and other documents American Assets Trust, Inc. and American Assets Trust, L.P. subsequently file pursuant to Section 13(a), 13(c), 14 or 15(d) of the Exchange Act prior to the termination of this offering but excluding any information furnished to, rather than filed with, the SEC, will also be incorporated by reference into this prospectus and deemed to be part of this prospectus from the date of the filing of such reports and documents.

You may request a free copy of any of the documents incorporated by reference in this prospectus (other than exhibits, unless they are specifically incorporated by reference in the documents) by writing or telephoning us at the following address:

AMERICAN ASSETS TRUST, INC.

11455 EL CAMINO REAL, SUITE 200

SAN DIEGO, CALIFORNIA 92130

ATTENTION: GENERAL COUNSEL

(858) 350-2600

Exhibits to the filings will not be sent, however, unless those exhibits have specifically been incorporated by reference in this prospectus and any accompanying prospectus supplement.

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THE COMPANY

The Company operates as a full service, vertically integrated and self-administered real estate investment trust, or REIT, that owns, operates, acquires and develops high quality retail, office, multifamily and mixed-use properties in attractive, high-barrier-to-entry markets in Southern California, Northern California, Oregon, Washington, Texas and Hawaii. As of December 31, 2020, our portfolio is comprised of twelve retail shopping centers; nine office properties; a mixed-use property consisting of a 369-room all-suite hotel and a retail shopping center; and six multifamily properties. Additionally, as of December 31, 2020, we owned land at three of our properties that we classified as held for development and construction in progress. Our core markets include San Diego, the San Francisco Bay Area, Portland, Oregon, Bellevue, Washington and Oahu, Hawaii.

The Company is a Maryland corporation that was formed on July 16, 2010, and elected to be taxed as a REIT for federal income tax purposes commencing with the Company’s taxable year ended December 31, 2011. The Company intends to continue operating in a manner that will allow it to maintain its qualification as a REIT for federal income tax purposes. To maintain REIT status, the Company must meet a number of organizational and operational requirements, including a requirement that we annually distribute at least 90% of its REIT taxable income (excluding net capital gain) to its stockholders.

Our principal executive office is located at 11455 El Camino Real, Suite 200, San Diego, California 92130, and our telephone number is (858) 350-2600.

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RISK FACTORS

Investment in any securities offered pursuant to this prospectus and the applicable prospectus supplement involves risks. You should carefully consider the risk factors incorporated by reference to American Assets Trust, Inc.’s most recent Annual Report on Form 10-K and any subsequent Quarterly Reports on Form 10-Q or Current Reports on Form 8-K, any subsequent Annual Reports on Form 10-K, Quarterly Reports on Form 10-Q or Current Reports on Form 8-K American Assets Trust, L.P. files after the date of this prospectus, and all other information contained or incorporated by reference into this prospectus, as updated by our subsequent filings under the Exchange Act, and the risk factors and other information contained in the applicable prospectus supplement before acquiring any of such securities. The occurrence of any of these risks might cause you to lose all or part of your investment in the offered securities.

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GUARANTOR DISCLOSURES

American Assets Trust, Inc. may guarantee debt securities of the operating partnership as described in “Description of Debt Securities and Related Guarantees.” Any such guarantees by American Assets Trust, Inc. will be full, irrevocable, unconditional and absolute joint and several guarantees to the holders of each series of such outstanding guaranteed debt securities. The Company owns all of its assets and conducts all of its operations through the operating partnership and the operating partnership is consolidated into the Company’s financial statements.

In March 2020, the SEC adopted amendments to Rule 3-10 of Regulation S-X and created Rule 13-01 to simplify disclosure requirements related to certain registered securities. The Company and the operating partnership have filed this prospectus with the SEC registering, among other securities, debt securities of the operating partnership, which will be fully and unconditionally guaranteed by the Company. As a result of the amendments to Rule 3-10 of Regulation S-X, subsidiary issuers of obligations guaranteed by the parent are no longer required to provide separate financial statements, provided that the subsidiary obligor is consolidated into the parent company’s consolidated financial statements, the parent guarantee is “full and unconditional” and, subject to certain exceptions as set forth below, the alternative disclosure required by Rule 13-01 is provided, which includes narrative disclosure and summarized financial information. Accordingly, separate consolidated financial statements of the operating partnership are not expected to be presented or incorporated by reference for future periods.

Furthermore, as permitted under Rule 13-01(a)(4)(vi) of Regulation S-X, we do not expect to present or incorporate by reference summarized financial information for the operating partnership going forward because the assets, liabilities and results of operations of the operating partnership are not materially different than the corresponding amounts in American Assets Trust, Inc.’s consolidated financial statements that have been and will be incorporated by reference herein, and management believes such summarized financial information would be repetitive and would not provide incremental value to investors.

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USE OF PROCEEDS

Our operating partnership intends to use the net proceeds from any sale of the securities pursuant to this prospectus to potentially acquire or develop additional properties and for general corporate purposes, which may include payment of dividends, the repayment of existing indebtedness and capital expenditures for improvements to the properties in our portfolio. Pending application of cash proceeds, we will invest the net proceeds in interest-bearing accounts, money market accounts and interest-bearing securities in a manner that is consistent with the Company’s intention to continue to qualify for taxation as a REIT. Such investments may include, for example, government and government agency certificates, government bonds, certificates of deposit, interest-bearing bank deposits, money market accounts and mortgage loan participations. Further details regarding the use of the net proceeds from the sale of a specific series or class of the securities will be set forth in the applicable prospectus supplement.

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DESCRIPTION OF DEBT SECURITIES AND RELATED GUARANTEES

This section describes the general terms and provisions of the operating partnership’s debt securities. When our operating partnership offers to sell a particular series of debt securities, we will describe the specific terms of the series in a supplement to this prospectus, along with any applicable modifications of or additions to the general terms of the debt securities as described in this prospectus, including the terms of any related guarantees by the Company and the terms, if any, on which a series of debt securities may be convertible into or exchangeable for other securities. To the extent the information contained in the prospectus supplement differs from this summary description, you should rely on the information in the prospectus supplement.

The debt securities may be offered either separately, or together with, or upon the conversion or exercise of or in exchange for, other securities described in this prospectus. Debt securities may be the operating partnership’s senior, senior subordinated or subordinated obligations and may be issued in one or more series. Unless otherwise specified in the applicable prospectus supplement, the debt securities will be the operating partnership’s direct, unsecured senior obligations and will rank equally in right of payment with all of its other senior unsecured indebtedness.

Unless otherwise specified in a prospectus supplement, the debt securities will be issued under the indenture to be entered into among the operating partnership, the Company and U.S. Bank National Association, as trustee, a form of which has been filed as an exhibit to the Registration Statement of which this prospectus is a part (the “indenture”). The indenture contains the full legal text of the matters described in this section. We have summarized select portions of the indenture below. The summary is not complete and is subject to and qualified in its entirety by reference to all the provisions of the indenture, including definitions of the terms used in the indenture. Whenever we refer to particular sections or defined terms of the indenture in this prospectus or in a prospectus supplement, those sections or defined terms are incorporated by reference into this prospectus or the applicable prospectus supplement, and this summary also is subject to and qualified by reference to the description of the particular terms of a particular series of debt securities described in the applicable prospectus supplement. You should read the indenture for provisions that may be important to you. Capitalized terms used in the summary and not defined herein have the meanings specified in the indenture.

As used in this “Description of Debt Securities and Related Guarantees,” references to the “operating partnership,” “we,” “our” or “us” refer solely to American Assets Trust, L.P. and not to any of its subsidiaries and references to the “Company” or “guarantor” refer solely to American Assets Trust, Inc. and not to any of its subsidiaries, unless otherwise expressly stated or the context otherwise requires.

General

The terms of each series of debt securities will be established by or pursuant to a resolution of the Company’s board of directors and set forth or determined in the manner provided in a resolution of the Company’s board of directors, in an officer’s certificate or by a supplemental indenture. The particular terms of each series of debt securities, along with any applicable modifications of or additions to the general terms of the debt securities as described in this prospectus, will be described in a prospectus supplement relating to such series (including any pricing supplement or term sheet). A prospectus supplement, pricing supplement or term sheet may change any of the terms of the debt securities described in this prospectus.

Unless we state otherwise in the applicable prospectus supplement, we can issue an unlimited amount of the operating partnership’s debt securities under the indenture that may be in one or more series with the same or various maturities, at par, at a premium, or at a discount. We will set forth in a prospectus supplement (including any pricing supplement or term sheet) relating to any series of debt securities being offered, the aggregate principal amount and the following terms of the debt securities, if applicable:

• the title and ranking of the debt securities;

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• the price or prices (expressed as a percentage of the principal amount) at which we will sell the debt securities;

• any limit on the aggregate principal amount of the debt securities;

• the date or dates on which we will pay the principal of and premium, if any, on the debt securities;

• the rate or rates (which may be fixed or variable) per annum or the method used to determine the rate or rates (including any commodity, commodity index, stock exchange index or financial index) at which the debt securities will bear interest, the date or dates from which interest will accrue, the date or dates on which interest will commence and be payable and any regular record date for the interest payable on any interest payment date;

• the place or places where principal of, premium, if any, and interest on the debt securities will be payable;

• the price or prices and the terms and conditions upon which we may redeem the debt securities;

• any obligation we have to redeem or purchase the debt securities pursuant to any sinking fund or analogous provisions or at the option of a holder of debt securities;

• the dates on which and the price or prices at which we will repurchase debt securities at the option of the holders of debt securities and other detailed terms and provisions of these repurchase obligations;

• the denominations in which the debt securities will be issued, if other than denominations of $2,000 and any integral multiple of $1,000 in excess thereof;

• whether the debt securities will be issued in the form of certificated debt securities or global debt securities;

• the portion of principal amount of the debt securities payable upon declaration of acceleration of the maturity date, if other than the entire principal amount;

• if other than U.S. dollars, the designation of the currency, currencies or currency units in which payment of principal of, premium and interest on the debt securities will be made and, if payments of principal, premium or interest on the debt securities will be made in one or more currencies or currency units other than that or those in which the debt securities are denominated, the manner in which the exchange rate with respect to these payments will be determined;

• the manner in which the amounts of payment of principal of, premium, if any, or interest on the debt securities will be determined, if these amounts may be determined by reference to an index based on a currency or currencies other than that in which the debt securities are denominated or designated to be payable or by reference to a commodity, commodity index, stock exchange index or financial index;

• any provisions relating to any security provided for the debt securities or the guarantees, if any, thereof;

• any addition to, deletion of or change in the Events of Default described in this prospectus or in the indenture with respect to the debt securities and any change in the acceleration provisions described in this prospectus or in the indenture with respect to the debt securities;

• any addition to, deletion of or change in the covenants described in this prospectus or in the indenture with respect to the debt securities;

• any depositaries, interest rate calculation agents, exchange rate calculation agents or other agents with respect to the debt securities;

• the provisions, if any, relating to conversion or exchange of any debt securities of the series, including if applicable, the conversion or exchange price, the conversion or exchange period, the securities or other property into which such debt securities will be convertible or exchangeable, provisions as to whether conversion or exchange will be mandatory, at the option of the holders thereof or at our option, the events requiring an adjustment of the conversion or exchange price and provisions affecting conversion or exchange if such debt securities are redeemed;

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• whether the debt securities of the series will be senior debt securities, senior subordinated debt securities or subordinated debt securities and, if applicable, the subordination terms thereof;

• whether the debt securities of the series are guaranteed by the Company, the terms of the guarantee and whether any guarantee is made on a senior, senior subordinated or subordinated basis and, if applicable, the subordination terms of any guarantee; and

• any other terms of the debt securities, which may supplement, modify or delete any provision of the indenture as it applies to that series.

As discussed above, we may issue debt securities of the operating partnership that provide for an amount less than their stated principal amount to be due and payable upon declaration of acceleration of their maturity pursuant to the terms of the indenture. In addition, we may denominate the purchase price of any of the debt securities in a foreign currency or currencies or a foreign currency unit or units, and the principal of and any premium and interest on any series of debt securities may be payable in a foreign currency or currencies or a foreign currency unit or units. The applicable prospectus supplement will provide you with information on the federal income tax considerations and other special considerations applicable to any such debt securities.

No Protection in the Event of a Change of Control

Unless we state otherwise in the applicable prospectus supplement, the debt securities of any series will not contain any provisions which may afford holders of the debt securities of such series protection in the event the operating partnership or the Company has a change of control or in the event of a highly leveraged transaction (whether or not such transaction results in a change of control), which could adversely affect holders of debt securities.

Covenants

We will set forth in the applicable prospectus supplement any restrictive covenants applicable to any issue of any series of debt securities.

Merger, Consolidation and Sale of Assets

Unless we state otherwise in the applicable prospectus supplement, the operating partnership and the Company may consolidate with, or sell, lease or convey all or substantially all of their respective assets to, or merge with or into, any other entity, provided that the following conditions are met:

• the operating partnership or the Company, as the case may be, shall be the continuing entity, or the successor entity (if other than the operating partnership or the Company, as the case may be) formed by or resulting from any consolidation or merger or which shall have received the transfer of assets shall be organized and existing under the laws of the United States, any state thereof or the District of Columbia and shall expressly assume, in the case of the operating partnership, payment of the principal of and premium, if any, and interest and any redemption price due on all of the debt securities and the due and punctual performance and observance of all of the covenants and conditions of the operating partnership in the indenture and the debt securities, or in the case of the Company, the payment of all amounts due under its guarantees of the debt securities and the due and punctual performance and observance of all of the covenants and conditions of the Company in the indenture and the guarantees, as the case may be;

• immediately after giving effect to the transaction, no Event of Default under the indenture, and no event which, after notice or the lapse of time, or both, would become an Event of Default, shall have occurred and be continuing; and

• an officer’s certificate and legal opinion covering these conditions shall be delivered to the trustee.

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Upon any such merger, consolidation or conveyance, the resulting, surviving or transferee person shall succeed to, and may exercise every right and power of, the operating partnership or the Company, as the case may be, under the indenture.

Events of Default

Unless we state otherwise in the applicable prospectus supplement, the indenture provides that the following events are “Events of Default” with respect to any series of debt securities:

• default in the payment of any interest on the debt securities of such series when such interest becomes due and payable that continues for a period of 30 days;

• default in the payment of any principal of or premium, if any, on the debt securities of such series, or any redemption price due with respect to the debt securities of such series, when due and payable;

• default in the deposit of any sinking fund payment, when and as due by the terms of any debt securities of such series;

• failure by the operating partnership or the Company to comply with their respective obligations described under “Merger, Consolidation and Sale of Assets”;

• default in the performance, or breach, of any other covenant or warranty of the operating partnership or the Company in the indenture (other than a covenant or warranty which has expressly been included in the indenture solely for the benefit of the debt securities of a series other than such series) and continuance of such default or breach for a period of 60 days after written notice as provided in the indenture;

• default under any bond, debenture, note, mortgage, indenture or instrument under which there may be issued or by which there may be secured or evidenced any indebtedness for money borrowed (other than Non-Recourse Debt) by the Company or the operating partnership or by any Significant Subsidiary of the operating partnership or the Company, the repayment of which the Company or the operating partnership has guaranteed or for which the Company or the operating partnership is directly responsible or liable as obligor or guarantor, having an aggregate principal amount outstanding of at least $25 million, whether such indebtedness exists as of the date of the indenture or shall thereafter be created, which default shall have resulted in such indebtedness becoming or being declared due and payable prior to the date on which it would otherwise have become due and payable, without such indebtedness having been discharged, or such acceleration having been rescinded or annulled, within the period specified in such instrument; provided, that if the cross-default amount applicable to recourse indebtedness specified in the credit agreement governing the Company’s second amended and restated credit facility, as such agreement may be amended, restated, extended, refinanced or replaced, is increased to exceed $25 million, the reference to $25 million in the foregoing clause shall be automatically replaced by such higher amount up to $50 million;

• a final judgment for the payment of $35 million or more (excluding any amounts covered by insurance) is rendered against the operating partnership, the Company or any of the operating partnership’s or the Company’s respective Significant Subsidiaries, which judgment is not discharged or stayed within 60 days after (1) the date on which the right to appeal thereof has expired if no such appeal has commenced, or (2) the date on which all rights to appeal have been extinguished; or

• certain events of bankruptcy, insolvency or reorganization with respect to the operating partnership, the Company or any Significant Subsidiary of the operating partnership or the Company.

A supplemental indenture or officer’s certificate establishing the terms of a particular series of debt securities may delete, modify or add to the Events of Default described above.

If an Event of Default with respect to the debt securities of a particular series occurs and is continuing (other than an Event of Default specified in the last bullet above, which shall result in an automatic acceleration), then in every case the trustee or the holders of not less than 25% in principal amount of the outstanding debt securities of such series may declare the principal amount of, and accrued and unpaid interest on, all of the debt securities

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of such series to be due and payable immediately by written notice thereof to the operating partnership and the Company (and to the trustee if given by the holders). However, at any time after the declaration of acceleration (or automatic acceleration) with respect to the debt securities of such series has occurred, but before a judgment or decree for payment of the money due has been obtained by the trustee, the holders of not less than a majority in principal amount of the debt securities of such series outstanding may rescind and annul the declaration and its consequences if:

• the operating partnership or the Company shall have deposited with the trustee all payments of the principal of and premium, if any, and interest on the debt securities of such series which have become due otherwise than by such acceleration, plus certain fees, expenses, disbursements and advances of the trustee; and

• all Events of Default, other than the non-payment of accelerated principal of and interest on the debt securities of such series, have been cured or waived as provided in the indenture.

The indenture also provides that the holders of not less than a majority in principal amount of the outstanding debt securities of any series may waive any past default or Event of Default with respect to the debt securities of such series and its consequences, except, among other things, a default:

• in the payment of the principal of or premium, if any, or interest on the debt securities of such series; or

• in respect of a covenant or provision contained in the indenture that cannot be modified or amended without the consent of the holders of each outstanding debt security affected thereby.

The trustee will be required to give notice to the holders of the debt securities of any particular series within 90 days of a default under the indenture with respect to the debt securities of such series known to a responsible officer (as defined in the indenture) of the trustee unless the default has been cured or waived; provided, however, that the trustee may withhold notice to the holders of the debt securities of such series of any default with respect to the debt securities of such series (except a default in the payment of the principal of or premium, if any or interest on the debt securities of such series) if responsible officers of the trustee in good faith determine the withholding to be in the interest of the holders of the debt securities of such series; and provided, further, that in the case of a default with respect to the debt securities of any series of the character specified in the penultimate bullet point of the first paragraph under this caption “Events of Default,” no such notice to holders of debt securities of such series shall be given until at least 60 days after the occurrence thereof.

The indenture provides that no holder of the debt securities of a particular series may institute any action or proceedings, judicial or otherwise, with respect to the indenture or for any remedy thereunder, unless:

• such holder has given the trustee written notice of an Event of Default and of the continuance thereof with respect to the debt securities of such series;

• the registered holders of at least 25% in aggregate principal amount of the outstanding debt securities of such series have made a written request upon the trustee to institute such action or proceeding and shall have offered to the trustee such indemnity or security reasonably satisfactory to it against costs, liabilities or expenses to be incurred therein or thereby;

• the trustee for 60 days after its receipt of such notice, request and offer of indemnity has failed to institute any such action, suit or proceeding; and

• no direction inconsistent with such written request shall have been given to the trustee by holders of a majority in an aggregate principal amount of the debt securities of such series then outstanding.

This provision will not prevent, however, any holder of the debt securities of any series from instituting suit for the enforcement of payment of the principal of or premium if any, or interest on such debt securities on or after the respective due dates thereof.

Subject to provisions in the indenture relating to its duties in case of default, the trustee will be under no obligation to exercise any of its rights or powers under the indenture at the request or direction of any holders of

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debt securities of any series then outstanding under the indenture, unless the holders of debt securities of such series shall have offered to the trustee security or indemnity satisfactory to the trustee. The holders of not less than a majority in principal amount of the outstanding debt securities of any series shall have the right to direct the time, method and place of conducting any proceeding for any remedy available to the trustee, or of exercising any trust or power conferred upon the trustee with respect to the debt securities of such series. However, the trustee may refuse to follow any direction which is in conflict with any law or the indenture or which may involve the trustee in personal liability or be unduly prejudicial to the holders of the debt securities of such series not joining therein.

Within 120 days after the close of each fiscal year, the operating partnership and the Company must deliver a certificate of an officer certifying to the trustee whether or not the officer has knowledge of any default under the indenture and, if so, specifying each default and the nature and status thereof.

As used in this subsection titled “—Events of Default”, the following terms have the respective meanings specified below:

“Non-Recourse Debt” means Debt of a Subsidiary of the operating partnership (or an entity in which the operating partnership is the general partner or managing member) that is directly or indirectly secured by real estate assets or other real estate-related assets (including equity interests) of a Subsidiary of the operating partnership (or entity in which the operating partnership is the general partner or managing member) that is the borrower and is non-recourse to the operating partnership or any Subsidiary of the operating partnership (other than pursuant to a Permitted Non-Recourse Guarantee and other than with respect to the Subsidiary of the operating partnership (or entity in which the operating partnership is the general partner or managing member) that is the borrower); provided, further, that, if any such Debt is partially recourse to the operating partnership or any Subsidiary of the operating partnership (other than pursuant to a Permitted Non-Recourse Guarantee and other than with respect to the Subsidiary of the operating partnership (or entity in which the operating partnership is the general partner or managing member) that is the borrower) and therefore does not meet the criteria set forth above, only the portion of such Debt that does meet the criteria set forth above shall constitute “Non-Recourse Debt.”

“Permitted Non-Recourse Guarantees” means customary completion or budget guarantees or indemnities (including by means of separate indemnification agreements and carve-out guarantees) provided under Non-Recourse Debt in the ordinary course of business by the operating partnership or any Subsidiary of the operating partnership in financing transactions that are directly or indirectly secured by real estate assets or other real estate-related assets (including equity interests) of a Subsidiary of the operating partnership (or entity in which the operating partnership is the general partner or managing member), in each case that is the borrower in such financing, but is non-recourse to the operating partnership or any of the operating partnership’s other Subsidiaries, except for customary completion or budget guarantees or indemnities (including by means of separate indemnification agreements or carve-out guarantees) as are consistent with customary industry practice (such as environmental indemnities and recourse triggers based on violation of transfer restrictions and other customary exceptions to nonrecourse liability).

“Significant Subsidiary” of any specified person means any Subsidiary in which such person has invested at least $50.0 million in capital.

“Subsidiary” means, with respect to the operating partnership or the Company, any person (as defined in the indenture but excluding an individual), a majority of the outstanding voting stock, partnership interests, membership interests or other equity interest, as the case may be, of which is owned or controlled, directly or indirectly, by the operating partnership or the Company, as the case may be, or by one or more other Subsidiaries of the operating partnership or the Company, as the case may be. For the purposes of this definition, “voting stock” means stock having voting power for the election of directors, trustees or managers, as the case may be, whether at all times or only so long as no senior class of stock has such voting power by reason of any contingency.

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Modification, Waiver and Meetings

Unless we state otherwise in the applicable prospectus supplement, modifications and amendments of the indenture will be permitted to be made pursuant to a supplemental indenture entered into by the operating partnership, the Company and the trustee with the consent of the holders of not less than a majority in principal amount of all outstanding debt securities of each series affected by such supplemental indenture (including consent obtained in connection with a tender offer or exchange offer for the outstanding debt securities of such series); provided, however, that no modification or amendment may, without the consent of the holder of each debt security affected thereby:

• change the stated maturity of the principal of or premium, if any, or any installment of interest on any debt security or reduce the principal amount of or premium, if any, or the rate or amount of interest on any debt security;

• change the place of payment, or the coin or currency, for payment of principal of or premium, if any, or interest on any debt security or impair the right to institute suit for the enforcement of any payment on or with respect to any debt security;

• reduce the above-stated percentage of outstanding debt securities of any series necessary to modify or amend the indenture, to waive compliance with certain provisions thereof or certain defaults and their consequences thereunder or to reduce the quorum or change voting requirements set forth in the indenture;

• modify or affect in any manner adverse to the holders of any debt security the terms and conditions of the obligations of the Company, as guarantor, in respect of the payment of principal, premium, if any, and interest; or

• modify any of the foregoing provisions or any of the provisions relating to the waiver of certain defaults or Events of Default with respect to debt securities of any series, or the waiver of compliance with certain covenants applicable to the debt securities of any series, except to increase the percentage required to effect the action or to provide that certain other provisions may not be modified or waived without the consent of the holders of each of the debt securities affected thereby.

Notwithstanding the foregoing, modifications and amendments of the indenture will be permitted to be made by supplemental indenture executed by the operating partnership, the Company and the trustee without the consent of any holder of the debt securities for, among other things, any of the following purposes:

• to evidence a successor to the operating partnership as obligor or the Company as guarantor under the indenture;

• to add to the covenants of the operating partnership or the Company for the benefit of the holders of the debt securities of all or any series and any related guarantees or to surrender any right or power conferred upon the operating partnership or the Company in the indenture with respect to all or any series of debt securities or any related guarantees;

• to add Events of Default for the benefit of the holders of the debt securities of all or any series;

• to amend or supplement any provisions of the indenture with respect to the debt securities of all or any series, provided that no amendment or supplement shall adversely affect the interests of the holders of such debt securities in any respect;

• to secure the debt securities of all or any series;

• to provide for the acceptance of appointment by a successor trustee in respect of all or any series of debt securities or facilitate the administration of the trusts under the indenture by more than one trustee;

• to cure any ambiguity, defect or inconsistency in the indenture; provided that the action shall not adversely affect the interests of holders of the debt securities of any series in any respect;

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• to establish the form or terms of debt securities of any series and any related guarantees, and any deletions from or additions or changes to the indenture in connection therewith (provided that any such deletions, additions and changes shall not be applicable to any other debt securities then outstanding or to any other series of debt securities);

• to delete, amend or supplement any provision contained in the indenture or in any supplemental indenture (which deletion, amendment or supplement may apply to one or more series of debt securities or may apply to the indenture generally), provided that such deletion, amendment or supplement does not (i) apply to any debt securities of any series then outstanding created or issued prior to the date of the supplemental indenture pursuant to which such deletion, amendment or supplement is made and entitled to the benefit of such provision deleted, amended or supplemented by such supplemental indenture, or (ii) modify the rights of the holder of any such debt security;

• to comply with the Trust Indenture Act of 1939;

• to supplement any of the provisions of the indenture to the extent necessary to permit or facilitate satisfaction and discharge, legal defeasance or covenant defeasance of the debt securities of any series as described below under the caption “—Discharge, Defeasance and Covenant Defeasance”; provided that the action shall not adversely affect the interests of the holders of the debt securities of any series in any respect;

• to conform the provisions of the indenture, the debt securities or the related guarantee to this “Description of Debt Securities and Related Guarantees” and to the additional terms set forth in the applicable prospectus supplement; or

• to add guarantors for the benefit of the debt securities of all or any series.

The operating partnership and the Company may omit in any particular instance to comply with certain specified covenants in the indenture with respect to the debt securities of any series (which, if expressly stated in the prospectus supplement applicable to the debt securities of such series, may include any additional covenants specified in such prospectus supplement) if the holders of at least a majority in principal amount of all outstanding debt securities of such series waive such compliance. In determining whether the holders of the requisite principal amount of outstanding debt securities have given any request, demand, authorization, direction, notice, consent or waiver under the indenture or whether a quorum is present at a meeting of holders of debt securities, the indenture provides that debt securities owned by the operating partnership, the Company or any other obligor upon the debt securities or the guarantees thereof or any affiliate of the operating partnership, the Company, or of any other such obligor shall be disregarded.

The indenture contains provisions for convening meetings of the holders of debt securities of any series. A meeting of the holders of debt securities of any series will be permitted to be called at any time by the trustee, and also, upon request, by the operating partnership or the holders of at least 25% in principal amount of the outstanding debt securities of such series, in any case upon notice given as provided in the indenture. Except for any consent that must be given by the holder of each debt security affected by certain modifications and amendments of the indenture, any resolution presented at a meeting or adjourned meeting duly reconvened at which a quorum is present will be permitted to be adopted by the affirmative vote of the holders of a majority in principal amount of the outstanding debt securities of such series; provided, however, that, except for any consent that must be given by the holder of each debt security affected as referred to above, any resolution with respect to any request, demand, authorization, direction, notice, consent, waiver or other action that may be made, given or taken by the holders of a specified percentage, which is less than a majority, in principal amount of the outstanding debt securities of such series may be adopted at a meeting or adjourned meeting duly reconvened at which a quorum is present by the affirmative vote of the holders of the specified percentage in principal amount of the outstanding debt securities of such series. Any resolution passed or decision taken at any meeting of holders of debt securities of any series duly held in accordance with the indenture will be binding on all holders of the debt securities of such series. The quorum at any meeting called to adopt a resolution, and at any reconvened meeting, of the debt securities of any series will be holders of a majority in principal amount of

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the outstanding debt securities of such series; provided, however, that if any action is to be taken at the meeting with respect to a request, demand, authorization, direction, notice, consent, waiver or other action which may be given by the holders of not less than a specified percentage in principal amount of the outstanding debt securities of such series, holders of the specified percentage in principal amount of the outstanding debt securities of such series will constitute a quorum with respect to that matter. In the absence of a quorum at the reconvening of any adjourned meeting, such adjourned meeting may be further adjourned for a period of not less than ten days; at the reconvening of any meeting adjourned or further adjourned for lack of a quorum, the persons entitled to vote 25% in aggregate principal amount of the then outstanding debt securities of such series shall constitute a quorum.

Notwithstanding the foregoing provisions, if any action is to be taken at a meeting of holders of debt securities of any series with respect to any request, demand, authorization, direction, notice, consent, waiver or other action that the indenture expressly provides may be taken by holders of such series and one or more additional series acting collectively and voting together as a single class, there shall be no minimum quorum requirement for that meeting and the principal amount of outstanding debt securities of all such series that are entitled to vote in favor of that request, demand, authorization, direction, notice, consent, waiver or other action shall be taken into account in determining whether such action has been made, given or taken under the indenture.

Discharge, Defeasance and Covenant Defeasance

Unless we state otherwise in the applicable prospectus supplement, the indenture shall cease to be of further effect with respect to any series of debt securities, and the Company shall be released from its guarantee of the debt securities of such series (subject to the survival of a limited number of specified provisions) when:

• either (A) all outstanding debt securities of such series have been delivered to the trustee for cancellation (subject to specified exceptions) or (B) all outstanding debt securities of such series have become due and payable or will become due and payable at their maturity date within one year or are to be called for redemption on a redemption date within one year and the operating partnership has deposited with the trustee, in trust, funds in an amount sufficient to pay the entire indebtedness on the outstanding debt securities of such series not theretofore delivered to the trustee for cancellation in respect of principal, premium, if any, and interest, to the date of such deposit (if the debt securities of such series have become due and payable) or to the maturity date or redemption date, as the case may be;

• the operating partnership has paid or caused to be paid all other sums payable under the indenture with respect to the debt securities of such series; and

• certain other conditions are met.

The indenture provides that the operating partnership may elect:

• to be discharged from any and all obligations in respect of the debt securities of any series (subject to the survival of a limited number of specified provisions) (“legal defeasance”); or

• to be released from compliance with specified covenants in the indenture in respect of the debt securities of any series (“covenant defeasance”).

To effect legal defeasance or covenant defeasance, the operating partnership will be required to make an irrevocable deposit with the trustee, in trust for such purpose, of money and/or government obligations (as defined in the indenture) that, through the scheduled payment of interest and principal in accordance with their terms, will provide money in an amount sufficient to pay and discharge the principal, premium, if any, and interest on the debt securities of such series on the scheduled due dates or the applicable redemption date, as the case may be, in accordance with the terms of the indenture and the debt securities of such series. Upon any legal defeasance (but not covenant defeasance) the Company will be released from its guarantee of the debt securities of such series.

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The trust described in the preceding paragraph may only be established if, among other things:

• the operating partnership has delivered to the trustee a legal opinion of outside counsel reasonably acceptable to the trustee to the effect that the holders of the debt securities of such series will not recognize income, gain or loss for U.S. federal income tax purposes as a result of such legal defeasance or covenant defeasance and will be subject to U.S. federal income tax on the same amounts, in the same manner and at the same times as would have been the case if such legal defeasance or covenant defeasance had not occurred, and such legal opinion, in the case of legal defeasance, must refer to and be based upon a ruling of the Internal Revenue Service, or IRS, or a change in applicable U.S. federal income tax law occurring after the date of the indenture;

• if the cash and government obligations deposited are sufficient to pay the principal of, and premium, if any, and interest (including the redemption price) on the debt securities of such series, provided such debt securities of such series are redeemed on a particular redemption date, the operating partnership shall have given the trustee irrevocable instructions to redeem the debt securities of such series on the date and to provide notice of the redemption to the holders of the debt securities of such series;

• such legal defeasance or covenant defeasance will not result in a breach or violation of, or constitute a default under, the indenture or any other material agreement or instrument to which the operating partnership or the Company is a party or by which either of them is bound; and

• no Event of Default or event which with notice or lapse of time or both would become an Event of Default with respect to the debt securities of such series shall have occurred and shall be continuing on the date of, or, solely in the case of events of default due to certain events of bankruptcy, insolvency, or reorganization, during the period ending on the 91st day after the date of, such deposit into trust.

In the event we effect covenant defeasance with respect to the debt securities of any series, then any failure by the operating partnership or the Company to comply with any covenant as to which there has been covenant defeasance will not constitute an Event of Default. However, if the debt securities of such series are declared due and payable because of the occurrence of any other Event of Default, the amount of monies and/or government obligations deposited with the trustee to effect such covenant defeasance may not be sufficient to pay amounts due on the debt securities of such series at the time of any acceleration resulting from such Event of Default. However, the operating partnership and the Company would remain liable to make payment of such amounts due at the time of acceleration.

Governing Law

The indenture, the debt securities and any guarantees endorsed on the certificates evidencing the debt securities will be governed by, and construed in accordance with, the internal laws of the State of New York.

Book-entry System

The Global Notes

The debt securities of each series will be initially issued in the form of one or more registered debt securities in global form, without interest coupons, or the global notes. Upon issuance, each of the global notes will be deposited with the trustee as custodian for The Depository Trust Company, or DTC, and registered in the name of Cede & Co., as nominee of DTC.

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Ownership of beneficial interests in a global note will be limited to persons who have accounts with DTC, or DTC participants, or persons who hold interests through DTC participants. We expect that under procedures established by DTC:

• upon deposit of a global note with DTC’s custodian, DTC will credit portions of the principal amount of the global note to the accounts of the DTC participants designated by the applicable underwriters; and

• ownership of beneficial interests in a global note will be shown on, and transfer of ownership of those interests will be effected only through, records maintained by DTC (with respect to interests of DTC participants) and the records of DTC participants (with respect to other owners of beneficial interests in the global note).

Beneficial interests in global notes may not be exchanged for notes in physical, certificated form except in the limited circumstances described below.

Book-entry Procedures for the Global Notes

All interests in the global notes will be subject to the operations and procedures of DTC. We provide the following summary of those operations and procedures solely for the convenience of investors. The operations and procedures of DTC are controlled by that settlement system and may be changed at any time. None of the operating partnership, the Company or the applicable underwriters are responsible for those operations or procedures.

DTC has advised us that it is:

• a limited purpose trust company organized under the laws of the State of New York;

• a “banking organization” within the meaning of the New York State Banking Law;

• a member of the Federal Reserve System;

• a “clearing corporation” within the meaning of the Uniform Commercial Code; and

• a “clearing agency” registered under Section 17A of the Exchange Act.

DTC was created to hold securities for its participants and to facilitate the clearance and settlement of securities transactions between its participants through electronic book-entry changes to the accounts of its participants. DTC’s participants include securities brokers and dealers, including underwriters, banks and trust companies, clearing corporations and other organizations. Indirect access to DTC’s system is also available to others such as banks, brokers, dealers and trust companies; these indirect participants clear through or maintain a custodial relationship with a DTC participant, either directly or indirectly. Investors who are not DTC participants may beneficially own securities held by or on behalf of DTC only through DTC participants or indirect participants in DTC.

So long as DTC’s nominee is the registered owner of a global note, that nominee will be considered the sole owner or holder of the debt securities represented by that global note for all purposes under the indenture. Except as provided below, owners of beneficial interests in a global note:

• will not be entitled to have debt securities represented by the global note registered in their names;

• will not receive or be entitled to receive physical, certificated debt securities; and

• will not be considered the owners or holders of the debt securities under the indenture for any purpose, including with respect to the giving of any direction, instruction or approval to the trustee under the indenture.

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As a result, each investor who owns a beneficial interest in a global note of any series must rely on the procedures of DTC to exercise any rights of a holder of debt securities of such series under the indenture (and, if the investor is not a participant or an indirect participant in DTC, on the procedures of the direct, or, if applicable, indirect DTC participant through which the investor owns its interest).

Payments of principal, premium, if any, and interest with respect to the debt securities represented by a global note will be made by the trustee to DTC or DTC’s nominee as the registered holder of the global note. Neither the operating partnership, the Company nor the trustee will have any responsibility or liability for the payment of amounts to owners of beneficial interests in a global note, for any aspect of the records relating to or payments made on account of those interests by DTC, or for maintaining, supervising or reviewing any records of DTC relating to those interests.

Payments by participants and indirect participants in DTC to the owners of beneficial interests in a global note will be governed by standing instructions and customary industry practice and will be the responsibility of those participants or indirect participants and DTC.

Transfers between participants in DTC will be effected under DTC’s procedures and will be settled in same-day funds.

Certificated Notes

If the debt securities of any series are initially issued as global notes, debt securities of such series in physical, certificated form will be issued and delivered to each person that DTC identifies as a beneficial owner of the debt securities of such series only if:

• DTC notifies the operating partnership at any time that it is unwilling or unable to continue as depositary for the global notes of such series and a successor depositary is not appointed within 90 days;

• DTC ceases to be registered as a clearing agency under the Exchange Act at any time when the depositary is required to be so registered and a successor depositary is not appointed within 90 days after the operating partnership learns of such ineligibility;

• an Event of Default has occurred and is continuing under the indenture with respect to the debt securities of such series; or;

• we, at our option, determine that the debt securities of such series shall no longer be represented by global notes.

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DESCRIPTION OF THE PARTNERSHIP AGREEMENT OF AMERICAN ASSETS TRUST, L.P.

We have summarized the material terms and provisions of the Amended and Restated Agreement of Limited Partnership of American Assets Trust, L.P., which we refer to as the “partnership agreement.” This summary is not complete. For more detail, you should refer to the partnership agreement itself, a copy of which is filed with the SEC and is incorporated by reference as an exhibit to the registration statement of which this prospectus is a part. For purposes of this section, references to “we,” “our,” “us,” “our company” and the “general partner” refer to American Assets Trust, Inc. in our capacity as the general partner of our operating partnership.

General

Substantially all of the Company’s assets are held by, and substantially all of the Company’s operations are conducted through, our operating partnership, either directly or through its subsidiaries. The Company is the sole general partner of our operating partnership and, as of December 31, 2020, the Company owned an approximate 78.75% partnership interest in the operating partnership.

Certain persons who contributed interests in properties and/or other assets pursuant to the formation transactions related to the Company’s initial public offering received common units of partnership interest in our operating partnership, which we refer to as common units and have the terms described below. Our operating partnership is also authorized to issue a class of units of partnership interest designated as LTIP units, which have the terms described below. The units in the operating partnership are not listed on any exchange or quoted on any national market system.

Provisions in the partnership agreement may delay or make more difficult unsolicited acquisitions of us or changes in our control. These provisions could discourage third parties from making proposals involving an unsolicited acquisition of us or change of our control, although some stockholders might consider such proposals, if made, desirable. These provisions also make it more difficult for third parties to alter the management structure of our operating partnership without the concurrence of the Company’s board of directors. These provisions include, among others:

• redemption rights of limited partners and certain assignees of common units;

• transfer restrictions on units and other partnership interests;

• a requirement that the Company may not be removed as the general partner of our operating partnership without the Company’s consent;

• the Company’s ability in some cases to amend the partnership agreement and to cause our operating partnership to issue preferred partnership interests in our operating partnership with terms that we may determine, in either case, without the approval or consent of any limited partner; and

• the rights of the limited partners to consent to certain direct or indirect transfers of our interest in our operating partnership, including in connection with certain mergers, consolidations and other business combinations involving us, recapitalizations and reclassifications of the Company’s outstanding stock and issuances of the Company’s stock that require approval of the Company’s stockholders.

Purposes, Business and Management

Our operating partnership was formed for the purpose of conducting any business, enterprise or activity permitted by or under the Maryland Revised Uniform Limited Partnership Act. Our operating partnership may enter into any partnership, joint venture, business trust arrangement, limited liability company or other similar arrangement and may own interests in any entity engaged in any business permitted by or under the Maryland Revised Uniform Limited Partnership Act. However, our operating partnership may not, without our specific

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consent, which we may give or withhold in our sole and absolute discretion, take, or refrain from taking, any action that, in our judgment, in our sole and absolute discretion:

• could adversely affect the Company’s ability to continue to qualify as a REIT;

• could subject us to any taxes under Section 857 or Section 4981 of the Code or any other related or successor provision under the Code; or

• could violate any law or regulation of any governmental body or agency having jurisdiction over us, our securities or our operating partnership.

In general, the Company’s board of directors manages the business and affairs of our operating partnership by directing our business and affairs, in our capacity as the sole general partner of our operating partnership. Except as otherwise expressly provided in the partnership agreement and subject to the rights of holders of any class or series of partnership interest, all management powers over the business and affairs of our operating partnership are exclusively vested in us, in the Company’s capacity as the sole general partner of our operating partnership. The Company may not be removed as the general partner of our operating partnership, with or without cause, without the Company’s consent, which the Company may give or withhold in its sole and absolute discretion.

Restrictions on General Partner’s Authority

The partnership agreement prohibits the Company, in our capacity as general partner, from taking any action that would make it impossible to carry out the ordinary business of our operating partnership or performing any act that would subject a limited partner to liability as a general partner in any jurisdiction or any other liability except as provided under the partnership agreement. The Company generally may not, without the prior consent of the partners of our operating partnership (including the Company), amend, modify or terminate the partnership agreement, except for certain amendments described below that require the consent of a majority in interest of the limited partners (excluding the Company and any limited partner 50% or more of whose equity is owned, directly or indirectly, by the Company) and certain amendments described below that require the approval of each affected partner. The Company may not, in our capacity as the general partner of our operating partnership, without the consent of a majority in interest of the limited partners (excluding us and any limited partner 50% or more of whose equity is owned, directly or indirectly, by the Company):

• take any action in contravention of an express provision or limitation of the partnership agreement;

• transfer all or any portion of the Company’s general partnership interest in our operating partnership or admit any person as a successor general partner, subject to the exceptions described in “—Transfers of Partnership Interests—Restrictions on Transfers by the General Partner”;

• voluntarily withdraw as the general partner; or

• amend the partnership agreement to alter the restrictions on the general partner’s power to transfer all or any portion of its interest in our operating partnership or voluntarily withdraw as the general partner.

Without the consent of each affected limited partner, we may not enter into any contract, mortgage, loan or other agreement that expressly prohibits or restricts the Company or our operating partnership from performing the Company’s or our operating partnership’s specific obligations in connection with a redemption of units or expressly prohibits or restricts a limited partner from exercising its redemption rights in full. For the avoidance of doubt, because the Company has the right to elect to acquire common units tendered for redemption in exchange for shares of common stock, the approval of the limited partners generally should not be required in order for the Company or our operating partnership to enter into loan agreements which conditionally restrict our operating partnership from redeeming common units for cash. In addition to any approval or consent required by any other

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provision of the partnership agreement, the Company may not, without the consent of each affected partner, amend the partnership agreement or take any other action that would:

• convert a limited partner interest into a general partner interest (except as a result of our acquisition of that interest);

• modify the limited liability of a limited partner;

• alter the rights of any partner to receive the distributions to which such partner is entitled, or alter the allocations specified in the partnership agreement, except to the extent permitted by the partnership agreement in connection with the creation or issuance of any new class or series of partnership interest;

• alter or modify the redemption rights of holders of common units or the related definitions specified in the partnership agreement;

• remove, alter or amend certain provisions of the partnership agreement relating to the requirements for us to qualify as a REIT or permitting us to avoid paying tax under Sections 857 or 4981 of the Code; or

• amend the provisions of the partnership agreement requiring the consent of each affected partner before taking any of the actions described above.

Additional Partnership Interests and Limited Partners

The Company may cause our operating partnership to issue additional units or other partnership interests and to admit additional limited partners to our operating partnership from time to time, on such terms and conditions and for such capital contributions as the Company may establish in its sole and absolute discretion, without the approval or consent of any limited partner.

The partnership agreement authorizes our operating partnership to issue common units and LTIP units, and our operating partnership may issue additional partnership interests in one or more additional classes, or one or more series of any of such classes, with such designations, preferences, conversion or other rights, voting powers or rights, restrictions, limitations as to distributions, qualifications or terms or conditions of redemption (including, without limitation, terms that may be senior or otherwise entitled to preference over existing units) as the Company may determine, in its sole and absolute discretion, without the approval of any limited partner or any other person. Without limiting the generality of the foregoing, the Company may specify, as to any such class or series of partnership interest:

• the allocations of items of partnership income, gain, loss, deduction and credit to each such class or series of partnership interest;

• the right of each such class or series of partnership interest to share, on a junior, senior or pari passu basis, in distributions;

• the rights of each such class or series of partnership interest upon dissolution and liquidation of our operating partnership;

• the voting rights, if any, of each such class or series of partnership interest; and

• the conversion, redemption or exchange rights applicable to each such class or series of partnership interest.

If the Company issues shares of preferred stock, we anticipate that we will contribute the net proceeds of such issuance to our operating partnership in exchange for preferred units with substantially similar distribution rights.

Ability to Engage in Other Businesses; Conflicts of Interest

The Company may not conduct any business other than in connection with the ownership, acquisition and disposition of partnership interests, the management of the business and affairs of our operating partnership, the

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Company’s operations as a reporting company with a class (or classes) of securities registered under the Exchange Act, the Company’s operations as a REIT, the offering, sale, syndication, private placement or public offering of stock, bonds, securities or other interests, financing or refinancing of any type related to our operating partnership or its assets or activities and such activities as are incidental to those activities discussed above. In general, the Company must contribute any assets or funds that it acquires to our operating partnership in exchange for additional partnership interests. The Company may, however, in its sole and absolute discretion, from time to time hold or acquire assets in its own name or otherwise other than through our operating partnership so long as the Company takes commercially reasonable measures to ensure that the economic benefits and burdens of such property are otherwise vested in our operating partnership.

Distributions

Our operating partnership will make distributions at such times and in such amounts, as the Company may in its sole and absolute discretion determine:

• first, with respect to any partnership interests that are entitled to any preference in distribution, in accordance with the rights of the holders of such class(es) or series of partnership interest, and, within each such class, among the holders of such class pro rata in proportion to their respective percentage interests of such class; and

• second, with respect to any partnership interests that are not entitled to any preference in distribution, including the common units and, except as described below under “—LTIP Units” with respect to liquidating distributions and as may be provided in our Amended and Restated 2011 Equity Incentive Award Plan, or the 2011 Plan, or any other incentive award plan, or any applicable award agreement, the LTIP units, in accordance with the rights of the holders of such class(es) or series of partnership interest, and, within each such class, among the holders of each such class, pro rata in proportion to their respective percentage interests of such class.

Exculpation and Indemnification of General Partner

The partnership agreement provides that the Company is not liable to our operating partnership or any partner for monetary damages for losses sustained, liabilities incurred or benefits not derived by our operating partnership or any limited partner, except for liability for our intentional harm or gross negligence. The partnership agreement also provides that any obligation or liability in the Company’s capacity as the general partner of our operating partnership that may arise at any time under the partnership agreement or any other instrument, transaction or undertaking contemplated by the partnership agreement will be satisfied, if at all, out of the Company’s assets or the assets of our operating partnership only, and no such obligation or liability will be personally binding upon any of our directors, stockholders, officers, employees or agents.

In addition, the partnership agreement requires our operating partnership to indemnify the Company, its directors and officers, officers of our operating partnership and any other person designated by us against any and all losses, claims, damages, liabilities (whether joint or several), expenses (including, without limitation, attorneys’ fees and other legal fees and expenses), judgments, fines, settlements and other amounts arising from any and all claims, demands, actions, suits or proceedings, whether civil, criminal, administrative or investigative, that relate to the operations of our operating partnership, unless (1) an act or omission of the person was material to the matter giving rise to the action and either was committed in bad faith or was the result of active and deliberate dishonesty, (2) such person actually received an improper personal benefit in violation or breach of any provision of the partnership agreement or (3) in the case of a criminal proceeding, the person had reasonable cause to believe the act or omission was unlawful. Our operating partnership must also pay or reimburse the reasonable expenses of any such person upon its receipt of a written affirmation of the person’s good faith belief that the standard of conduct necessary for indemnification has been met and a written undertaking to repay any amounts paid or advanced if it is ultimately determined that the person did not meet the standard of conduct for indemnification. Our operating partnership will not indemnify or advance funds to any person with respect to any action initiated by the person seeking indemnification without our approval (except for

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any proceeding brought to enforce such person’s right to indemnification under the partnership agreement) or if the person is found to be liable to our operating partnership on any portion of any claim in the action.

Business Combinations and Dissolution of Our Operating Partnership

Subject to the limitations on the transfer of our interest in our operating partnership described in “—Transfers of Partnership Interests—Restrictions on Transfers by the General Partner,” the Company generally has the exclusive power to cause our operating partnership to merge, reorganize, consolidate, sell all or substantially all of its assets or otherwise combine its assets with another entity. The Company may also elect to dissolve our operating partnership without the consent of any limited partner. However, in connection with the acquisition of properties from persons to whom our operating partnership issues units or other partnership interests as part of the purchase price, in order to preserve such persons’ tax deferral, our operating partnership may contractually agree, in general, not to sell or otherwise transfer the properties for a specified period of time, or in some instances, not to sell or otherwise transfer the properties without compensating the sellers of the properties for their loss of the tax deferral.

Redemption Rights of Qualifying Parties

Beginning 14 months after first becoming a holder of common units, each limited partner and some assignees of limited partners will have the right, subject to the terms and conditions set forth in the partnership agreement, to require our operating partnership to redeem all or a portion of the common units held by such limited partner or assignee in exchange for a cash amount per common unit equal to the value of one share of our common stock, determined in accordance with and subject to adjustment under the partnership agreement. Our operating partnership’s obligation to redeem common units does not arise and is not binding against our operating partnership until the sixth business day after we receive the holder’s notice of redemption or, if earlier, the day we notify the holder seeking redemption that we have declined to acquire some or all of the common units tendered for redemption. If we do not elect to acquire the common units tendered for redemption in exchange for shares of the Company’s common stock (as described below), our operating partnership must deliver the cash redemption amount on or before the tenth business day after we receive the holder’s notice of redemption.

On or before the close of business on the fifth business day after a holder of common units gives notice of redemption to us, the Company may, in its sole and absolute discretion but subject to the restrictions on the ownership and transfer of the Company’s stock set forth in our charter, elect to acquire some or all of the common units tendered for redemption from the tendering party in exchange for shares of the Company’s common stock, based on an exchange ratio of one share of common stock for each common unit, subject to adjustment as provided in the partnership agreement. The partnership agreement does not require the Company to register, qualify or list any shares of common stock issued in exchange for common units with the SEC, with any state securities commissioner, department or agency, under the Securities Act or the Exchange Act or with any stock exchange.

Transfers of Partnership Interests

Restrictions on Transfers by Limited Partners

Until the expiration of 14 months after the date on which a limited partner first acquires a partnership interest, the limited partner generally may not directly or indirectly transfer all or any portion of its partnership interest without the Company’s consent, which it may give or withhold in its sole and absolute discretion, except for certain permitted transfers to certain affiliates, family members and charities, and certain pledges of partnership interests to lending institutions in connection with bona fide loans. After the expiration of 14 months after the date on which a limited partner first acquires a partnership interest, the limited partner will have the right to transfer all or any portion of its partnership interest without the Company’s consent to any person that is an “accredited investor,” within the meaning set forth in Rule 501 promulgated under the Securities Act, upon ten

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business days prior notice to us, subject to the satisfaction of conditions specified in the partnership agreement, including minimum transfer requirements and our right of first refusal.

Restrictions on Transfers by the General Partner

Except as described below, any transfer of all or any portion of the Company’s interest in our operating partnership, whether by sale, disposition, statutory merger or consolidation, liquidation or otherwise, must be approved by the consent of a majority in interest of the limited partners (excluding the Company and any limited partner 50% or more of whose equity is owned, directly or indirectly, by us). Subject to the rights of the Company’s stockholders and the limited partners of our operating partnership to approve certain direct or indirect transfers of the Company’s interests in our operating partnership described below and the rights of holders of any class or series of partnership interest, the Company may transfer all (but not less than all) of its general partnership interest without the consent of the limited partners, voting as a separate class, in connection with a merger, consolidation or other combination of its assets with another entity, a sale of all or substantially all of its assets or a reclassification, recapitalization or change in any outstanding shares of its stock if:

• in connection with such event, all of the limited partners will receive or have the right to elect to receive, for each common unit, the greatest amount of cash, securities or other property paid to a holder of one share of the Company’s common stock (subject to adjustment in accordance with the partnership agreement) in the transaction and, if a purchase, tender or exchange offer is made and accepted by holders of the Company’s common stock in connection with the event, each holder of common units receives, or has the right to elect to receive, the greatest amount of cash, securities or other property that the holder would have received if it had exercised its redemption right and received shares of the Company’s common stock in exchange for its common units immediately before the expiration of the purchase, tender or exchange offer and had accepted the purchase, tender or exchange offer; or

• substantially all of the assets of our operating partnership will be owned by a surviving entity (which may be our operating partnership) in which the limited partners of our operating partnership holding common units immediately before the event will hold a percentage interest based on the relative fair market value of the net assets of our operating partnership and the other net assets of the surviving entity immediately before the event, which interest will be on terms that are at least as favorable as the terms of the common units in effect immediately before the event and as those applicable to any other limited partners or non-managing members of the surviving entity and will include a right to redeem interests in the surviving entity for the consideration described in the preceding bullet or cash on similar terms as those in effect with respect to the common units immediately before the event, or, if common equity securities of the person controlling the surviving entity are publicly traded, such common equity securities.

The Company may also transfer all (but not less than all) of our interest in our operating partnership to a controlled affiliate of ours without the consent of any limited partner, subject to the rights of holders of any class or series of partnership interest.

The Company may not, without prior “partnership approval,” directly or indirectly transfer all or any portion of its interest in our operating partnership, before the later of the death of Mr. Rady and the death of his wife, in connection with a merger, consolidation or other combination of its assets with another entity, a sale of all or substantially all of its assets, a reclassification, recapitalization or change in any outstanding shares of its stock or other outstanding equity interests or an issuance of shares of its stock, in any case that requires approval by its common stockholders. The “partnership approval” requirement is satisfied, with respect to such a transfer, when the sum of the (1) the percentage interest of limited partners consenting to the transfer of the Company’s interest, plus (2) the product of (a) the percentage of the outstanding common units held by the Company multiplied by (b) the percentage of the votes that were cast in favor of the event by the Company’s common stockholders equals or exceeds the percentage required for the Company’s common stockholders to approve the event resulting in the transfer. Limited partners will be entitled to cast one vote for each common unit or LTIP unit, subject to adjustment under the partnership agreement.

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In addition, any transferee of the Company’s interest in our operating partnership must be admitted as a general partner of our operating partnership, assume, by operation of law or express agreement, all of the Company’s obligations as general partner under the partnership agreement, accept all of the terms and conditions of the partnership agreement and execute such instruments as may be necessary to effectuate the transferee’s admission as a general partner.

The Company may not voluntarily withdraw as the general partner of our operating partnership without the consent of a majority in interest of the limited partners (excluding the Company and any limited partner 50% or more of whose equity is owned, directly or indirectly, by the Company) other than upon the transfer of the Company’s entire interest in our operating partnership and the admission of the Company’s successor as a general partner of our operating partnership.

LTIP Units

Our operating partnership is authorized to issue a class of units of partnership interest designated as “LTIP units.” The Company may cause our operating partnership to issue LTIP units to persons who provide services to or for the benefit of our operating partnership, for such consideration or for no consideration as we may determine to be appropriate, and we may admit such persons as limited partners of our operating partnership, without the approval or consent of any limited partner. Further, the Company may cause our operating partnership to issue LTIP units in one or more classes or series, with such terms as it may determine, without the approval or consent of any limited partner. LTIP units may be subject to vesting, forfeiture and restrictions on transfer and receipt of distributions pursuant to the terms of any applicable equity-based plan and the terms of the 2011 Plan or any other award agreement relating to the issuance of the LTIP units.

Conversion Rights

Vested LTIP units are convertible at the option of each limited partner and some assignees of limited partners into common units, upon notice to the Company and our operating partnership, to the extent that the capital account balance of the LTIP unitholder with respect to all of his or her LTIP units is at least equal to our capital account balance with respect to an equal number of common units. The Company may cause our operating partnership to convert vested LTIP units eligible for conversion into an equal number of common units at any time, upon at least 10 and not more than 60 days’ notice to the holder of the LTIP units.

If the Company or our operating partnership is party to a transaction, including a merger, consolidation, sale of all or substantially all of our assets or other business combination, as a result of which common units are exchanged for or converted into the right, or holders of common units are otherwise entitled, to receive cash, securities or other property (or any combination thereof), the Company must cause our operating partnership to convert any vested LTIP units then eligible for conversion into common units immediately before the transaction, taking into account any special allocations of income that would be made as a result of the transaction. Our operating partnership must use commercially reasonable efforts to cause each limited partner (other than a party to such a transaction or an affiliate of such a party) holding LTIP units that will be converted into common units in such a transaction to be afforded the right to receive the same kind and amount of cash, securities and other property (or any combination thereof) for such common units that each holder of common units receives in the transaction.

Transfer

Unless the 2011 Plan, any other applicable equity-based plan or the terms of an award agreement specify additional restrictions on transfer of LTIP units, LTIP units are transferable to the same extent as common units, as described above in “—Transfers of Partnership Interests.”

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Voting Rights

Limited partners holding LTIP units are entitled to vote together with limited partners holding common units on all matters on which limited partners holding common units are entitled to vote or consent, and may cast one vote for each LTIP unit so held.

Adjustment of LTIP Units

If our operating partnership takes certain actions, including making a distribution of units on all outstanding common units, combining or subdividing the outstanding common units into a different number of common units or reclassifying the outstanding common units, the Company must adjust the number of outstanding LTIP units or subdivide or combine outstanding LTIP units to maintain a one-for-one conversion ratio and economic equivalence between common units and LTIP units.

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MATERIAL PROVISIONS OF MARYLAND LAW AND OF THE COMPANY’S CHARTER AND BYLAWS

The following summary of certain provisions of Maryland law and the Company’s charter and bylaws does not purport to be complete and is subject to and qualified in its entirety by reference to Maryland law and our charter and bylaws, copies of which are filed as exhibits to the registration statement of which this prospectus is a part. See “Where You Can Find More Information; Incorporation by Reference.”

The Company’s Board of Directors

The Company’s charter and bylaws provide that the number of directors of the company may be established, increased or decreased only by a majority of the Company’s entire board of directors but may not be fewer than the minimum number required under the MGCL nor, unless our bylaws are amended, more than 15.

We have elected by a provision of the Company’s charter to be subject to a provision of Maryland law requiring that, except as otherwise provided in the terms of any class or series of the Company’s stock, vacancies on the Company’s board of directors may be filled only by the remaining directors and that any individual elected to fill a vacancy will serve for the remainder of the full term of the class of directors in which the vacancy occurred and until his or her successor is duly elected and qualifies.

Removal of Directors

The Company’s charter provides that, subject to the rights of holders of one or more classes or series of preferred stock to elect or remove one or more directors, a director may be removed only for cause (as defined in the Company’s charter) and only by the affirmative vote of at least two-thirds of the votes entitled to be cast generally in the election of directors. This provision, when coupled with the exclusive power of the Company’s board of directors to fill vacant directorships, may preclude stockholders from removing incumbent directors except for cause and by a substantial affirmative vote and filling the vacancies created by such removal with their own nominees.

Business Combinations

Under the MGCL, certain “business combinations” (including a merger, consolidation, share exchange or, in certain circumstances specified under the statute, an asset transfer or issuance or reclassification of equity securities) between a Maryland corporation and any interested stockholder, or an affiliate of such an interested stockholder, are prohibited for five years after the most recent date on which the interested stockholder becomes an interested stockholder. Maryland law defines an interested stockholder as:

• any person who beneficially owns, directly or indirectly, 10% or more of the voting power of the corporation’s outstanding voting stock; or

• an affiliate or associate of the corporation who, at any time within the two-year period prior to the date in question, was the beneficial owner, directly or indirectly, of 10% or more of the voting power of the then outstanding voting stock of the corporation.

A person is not an interested stockholder under the statute if the board of directors approved in advance the transaction by which the person otherwise would have become an interested stockholder. In approving a transaction, however, a board of directors may provide that its approval is subject to compliance, at or after the time of the approval, with any terms and conditions determined by it.

After such five-year period, any such business combination must be recommended by the board of directors of the corporation and approved by the affirmative vote of at least:

• 80% of the votes entitled to be cast by holders of outstanding shares of voting stock of the corporation; and

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�� two-thirds of the votes entitled to be cast by holders of voting stock of the corporation other than shares held by the interested stockholder with whom (or with whose affiliate) the business combination is to be effected or held by an affiliate or associate of the interested stockholder.

These supermajority approval requirements do not apply if, among other conditions, the corporation’s common stockholders receive a minimum price (as defined in the MGCL) for their shares and the consideration is received in cash or in the same form as previously paid by the interested stockholder for its shares.

These provisions of the MGCL do not apply, however, to business combinations that are approved or exempted by a corporation’s board of directors prior to the time that the interested stockholder becomes an interested stockholder. The Company’s board of directors has, by board resolution, elected to opt out of the business combination provisions of the MGCL. However, we cannot assure you that the Company’s board of directors will not opt to be subject to such business combination provisions in the future. Notwithstanding the foregoing, an alteration or repeal of this resolution will not have any effect on any business combinations that have been consummated or upon any agreements existing at the time of such modification or repeal.

Control Share Acquisitions

The MGCL provides that holders of “control shares” of a Maryland corporation acquired in a “control share acquisition” have no voting rights with respect to any control shares except to the extent approved by the affirmative vote of at least two-thirds of the votes entitled to be cast in the election of directors, generally, excluding shares of stock in a corporation in respect of which any of the following persons is entitled to exercise or direct the exercise of the voting power of such shares in the election of directors: (1) the person who made or proposes to make a control share acquisition, (2) an officer of the corporation or (3) an employee of the corporation who is also a director of the corporation. “Control shares” are voting shares of stock that, if aggregated with all other such shares of stock previously acquired by the acquirer or in respect of which the acquirer is able to exercise or direct the exercise of voting power (except solely by virtue of a revocable proxy), would entitle the acquirer to exercise voting power in electing directors within one of the following ranges of voting power:

• one-tenth or more but less than one-third;

• one-third or more but less than a majority; or

• a majority or more of all voting power.

Control shares do not include shares that the acquiring person is then entitled to vote as a result of having previously obtained stockholder approval or shares acquired directly from the corporation. A “control share acquisition” means the acquisition, directly or indirectly, of ownership of, or the power to direct the exercise of voting power with respect to, issued and outstanding control shares, subject to certain exceptions.

A person who has made or proposes to make a control share acquisition, upon satisfaction of certain conditions (including an undertaking to pay expenses and making an “acquiring person statement” as described in the MGCL), may compel the corporation to call a special meeting of stockholders to be held within 50 days of demand to consider the voting rights of the control shares. If no request for a special meeting is made, the corporation may itself present the question at any stockholders meeting.

If voting rights of control shares are not approved at the meeting or if the acquiring person does not deliver an “acquiring person statement” as required by the statute, then, subject to certain conditions and limitations, the corporation may redeem any or all of the control shares (except those for which voting rights have previously been approved) for fair value determined, without regard to the absence of voting rights for the control shares, as of the date of any meeting of stockholders at which the voting rights of such shares are considered and not approved or, if no such meeting is held, as of the date of the last control share acquisition by the acquirer. If

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voting rights for control shares are approved at a stockholders meeting and the acquirer becomes entitled to vote a majority of the shares entitled to vote, all other stockholders may exercise appraisal rights. The fair value of the shares as determined for purposes of such appraisal rights may not be less than the highest price per share paid by the acquirer in the control share acquisition.

The control share acquisition statute does not apply to: (1) shares acquired in a merger, consolidation or share exchange if the corporation is a party to the transaction or (2) acquisitions approved or exempted by the charter or bylaws of the corporation.

The Company’s bylaws contain a provision exempting from the control share acquisition statute any and all acquisitions by any person of shares of our stock. We cannot provide you any assurance, however, that the Company’s board of directors will not amend or eliminate this provision at any time in the future.

Subtitle 8

Subtitle 8 of Title 3 of the MGCL permits a Maryland corporation with a class of equity securities registered under the Exchange Act and at least three independent directors to elect to be subject, by provision in its charter or bylaws or a resolution of its board of directors and notwithstanding any contrary provision in the charter or bylaws, to any or all of the following five provisions:

• a classified board;

• a two-thirds vote requirement for removing a director;

• a requirement that the number of directors be fixed only by vote of the directors;

• a requirement that a vacancy on the board be filled only by the remaining directors and for the remainder of the full term of the class of directors in which the vacancy occurred; or

• a majority requirement for the calling of a stockholder-requested special meeting of stockholders.

The Company has elected by a provision in the Company’s charter to be subject to the provisions of Subtitle 8 relating to the filling of vacancies on the Company’s board of directors. Through provisions in the Company’s charter and bylaws unrelated to Subtitle 8, the Company already (1) requires a two-thirds vote for the removal of any director from the board, which removal will be allowed only for cause, (2) vests in the board the exclusive power to fix the number of directorships, subject to limitations set forth in the Company’s charter and bylaws, and (3) requires, unless called by the chairman of the Company’s board of directors, the Company’s president, its chief executive officer or its board of directors, the request of stockholders entitled to cast not less than a majority of all votes entitled to be cast on a matter at such meeting to call a special meeting to consider and vote on any matter that may properly be considered at a meeting of stockholders. The Company has not elected to create a classified board. In the future, the Company’s board of directors may elect, without stockholder approval, to create a classified board or elect to be subject to one or more of the other provisions of Subtitle 8.

Amendments to the Company’s Charter and Bylaws

Other than amendments to certain provisions of the Company’s charter described below and amendments permitted to be made without stockholder approval under Maryland law or by a specific provision in the charter, the Company’s charter may be amended only if such amendment is declared advisable by the Company’s board of directors and approved by the affirmative vote of stockholders entitled to cast a majority of all of the votes entitled to be cast on the matter. The provisions of the Company’s charter relating to the removal of directors or specifying that the Company’s stockholders may act without a meeting only by unanimous consent, or the provision specifying the vote required to amend such provisions, may be amended only if such amendment is declared advisable by the Company’s board of directors and approved by the affirmative vote of stockholders entitled to cast not less than two-thirds of all of the votes entitled to be cast on the matter. The Company’s board of directors has the exclusive power to adopt, alter or repeal any provision of our bylaws or to make new bylaws.

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Transactions Outside the Ordinary Course of Business

The Company generally may not merge with or into, convert into or consolidate with another company, sell all or substantially all of the Company’s assets or engage in a statutory share exchange unless such transaction is declared advisable by the Company’s board of directors and approved by the affirmative vote of stockholders entitled to cast a majority of all of the votes entitled to be cast on the matter. In addition, to the extent that such a merger, conversion, consolidation, sale of assets of statutory share exchange would require the approval of our stockholders, such transaction may also require the approval of the limited partners of our operating partnership. See “Description of the Partnership Agreement of American Assets Trust, L.P.—Transfers of Partnership Interests—Restrictions on Transfers by the General Partner.”

Dissolution of the Company

The dissolution of the Company must be declared advisable by a majority of the Company’s entire board of directors and approved by the affirmative vote of stockholders entitled to cast a majority of all of the votes entitled to be cast on the matter.

Meetings of Stockholders

Under the Company’s bylaws, annual meetings of stockholders must be held each year at a date, time and place determined by our board of directors. Special meetings of stockholders may be called by the chairman of the Company’s board of directors, its chief executive officer, its president and its board of directors. Additionally, subject to the provisions of the Company’s bylaws, a special meeting of stockholders to act on any matter that may properly be considered at a meeting of stockholders must be called by our secretary upon the written request of stockholders entitled to cast a majority of all of the votes entitled to be cast on the matter at such meeting who have requested the special meeting in accordance with the procedures specified in our bylaws and provided the information and certifications required by our bylaws. Only matters set forth in the notice of a special meeting of stockholders may be considered and acted upon at such a meeting.

Advance Notice of Director Nominations and New Business

The Company’s bylaws provide that, with respect to an annual meeting of stockholders, nominations of individuals for election to the board of directors and the proposal of business to be considered by stockholders at the annual meeting may be made only:

• pursuant to the Company’s notice of the meeting;

• by or at the direction of the Company’s board of directors; or

• by a stockholder who was a stockholder of record both at the time of giving of the notice required by the Company’s bylaws and at the time of the annual meeting, who is entitled to vote at the meeting in the election of each individual so nominated or on such other business and who has provided the information and certifications required by the advance notice procedures set forth in our bylaws.

The Company’s bylaws provide that, with respect to special meetings of stockholders, only the business specified in our notice of meeting may be brought before the meeting of stockholders, and nominations of individuals for election to our board of directors may be made only:

• by or at the direction of the Company’s board of directors; or

• provided that the meeting has been called for the purpose of electing directors, by a stockholder who is a stockholder of record both at the time of giving of the notice required by the Company’s bylaws and at the time of the meeting, who is entitled to vote at the meeting in the election of each individual so nominated and who has provided the information and certifications required by the advance notice procedures set forth in the Company’s bylaws.

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The purpose of requiring stockholders to give advance notice of nominations and other proposals is to afford the Company’s board of directors the opportunity to consider the qualifications of the proposed nominees or the advisability of the other proposals and, to the extent considered necessary by our board of directors, to inform stockholders and make recommendations regarding the nominations or other proposals. The advance notice procedures also permit a more orderly procedure for conducting our stockholder meetings.

Anti-takeover Effect of Certain Provisions of Maryland Law and the Company’s Charter and Bylaws

The restrictions on ownership and transfer of the Company’s stock, the provisions of the Company’s charter regarding the removal of directors, the exclusive power of our board of directors to fill vacancies on the board and the advance notice provisions of the Company’s bylaws could delay, defer or prevent a transaction or a change of control of the Company that might involve a premium price for holders of the Company’s common stock or otherwise be in their best interests. Likewise, if the Company’s board of directors were to opt in to the business combination provisions of the MGCL or the provisions of Subtitle 8 of Title 3 of the MGCL providing for a classified board of directors, or if the provision in the Company’s bylaws opting out of the control share acquisition provisions of the MGCL were amended or rescinded, these provisions of the MGCL could have similar anti-takeover effects.

Indemnification and Limitation of Directors’ and Officers’ Liability

Maryland law permits a Maryland corporation to include in its charter a provision eliminating the liability of its directors and officers to the corporation and its stockholders for money damages except for liability resulting from actual receipt of an improper benefit or profit in money, property or services or active and deliberate dishonesty that is established by a final judgment and is material to the cause of action. The Company’s charter contains a provision that eliminates such liability to the maximum extent permitted by Maryland law.

The MGCL requires a Maryland corporation (unless its charter provides otherwise, which the Company’s charter does not) to indemnify a director or officer who has been successful, on the merits or otherwise, in the defense of any proceeding to which he or she is made or threatened to be made a party by reason of his or her service in that capacity. The MGCL permits a Maryland corporation to indemnify its present and former directors and officers, among others, against judgments, penalties, fines, settlements and reasonable expenses actually incurred by them in connection with any proceeding to which they may be made or are threatened to be made a party by reason of their service in those or other capacities unless it is established that:

• the act or omission of the director or officer was material to the matter giving rise to the proceeding and:

• was committed in bad faith; or

• was the result of active and deliberate dishonesty;

• the director or officer actually received an improper personal benefit in money, property or services; or

• in the case of any criminal proceeding, the director or officer had reasonable cause to believe that the act or omission was unlawful.

However, under the MGCL, a Maryland corporation may not indemnify a director or officer for an adverse judgment in a suit by or on behalf of the corporation or if the director or officer was adjudged liable on the basis that personal benefit was improperly received, unless in either case a court orders indemnification and then only for expenses. In addition, the MGCL permits a Maryland corporation to advance reasonable expenses to a director or officer, without requiring a preliminary determination of the director’s or officer’s ultimate entitlement to indemnification, upon the corporation’s receipt of:

i. a written affirmation by the director or officer of his or her good faith belief that he or she has met the standard of conduct necessary for indemnification by the corporation; and

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ii. a written undertaking by the director or officer or on the director’s or officer’s behalf to repay the amount paid or reimbursed by the corporation if it is ultimately determined that the director or officer did not meet the standard of conduct.

The Company’s charter authorizes us to obligate the Company and the Company’s bylaws obligate the Company, to the fullest extent permitted by Maryland law in effect from time to time, to indemnify and to pay or reimburse reasonable expenses in advance of final disposition of a proceeding, without requiring a preliminary determination of the director’s or officer’s ultimate entitlement to indemnification, to:

i. any present or former director or officer who is made or threatened to be made a party to the proceeding by reason of his or her service in that capacity; or

ii. any individual who, while serving as our director or officer and at our request, serves or has served as a director, officer, partner, trustee, member or manager of another corporation, real estate investment trust, limited liability company, partnership, joint venture, trust, employee benefit plan or other enterprise and who is made or threatened to be made a party to the proceeding by reason of his or her service in that capacity.

The Company’s charter and bylaws also permit us, with the approval of the Company’s board of directors, to indemnify and advance expenses to any person who served a predecessor of the Company in any of the capacities described above and to any employee or agent of the Company or a predecessor of the Company.

We have entered into indemnification agreements with each of the Company’s executive officers and directors whereby we have agreed to indemnify such executive officers and directors to the fullest extent permitted by Maryland law against all expenses and liabilities, subject to limited exceptions. These indemnification agreements also provide that, upon an application for indemnity by an executive officer or director to a court of appropriate jurisdiction, such court may order us to indemnify such executive officer or director.

The partnership agreement also provides that we, as general partner, and our directors, officers, employees, agents and designees are indemnified to the extent provided therein. See “Description of the Partnership Agreement of American Assets Trust, L.P.—Exculpation and Indemnification of General Partner.”

Insofar as the foregoing provisions permit indemnification of directors, officers or persons controlling us for liability arising under the Securities Act, we have been informed that in the opinion of the SEC, this indemnification is against public policy as expressed in the Securities Act and is therefore unenforceable.

Restrictions on Ownership and Transfer

Subject to certain exceptions, the Company’s charter provides that no person or entity may actually or beneficially own, or be deemed to own by virtue of the applicable constructive ownership provisions of the Code, more than 7.275% (in value or number of shares, whichever is more restrictive) of the outstanding shares of the Company’s common stock or more than 7.275% in value of the aggregate outstanding shares of our stock.

REIT Qualification

The Company’s charter provides that our board of directors may revoke or otherwise terminate our REIT election, without approval of our stockholders, if it determines that it is no longer in the Company’s best interests to continue to be qualified as a REIT.

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FEDERAL INCOME TAX CONSIDERATIONS

The discussion under the heading “Federal Income Tax Considerations” in Exhibit 99.1 to our Current Report on Form 8-K filed with the SEC on January 14, 2021 (the “January 2021 Form 8-K”) is incorporated by reference in this prospectus and may be obtained as described under “Where You Can Find More Information; Incorporation by Reference.” Prospective investors should carefully review the discussion appearing in Exhibit 99.1 to the January 2021 Form 8-K, as well as the other information included and incorporated by reference in this prospectus, before acquiring any securities pursuant to this prospectus.

Prospective investors in any securities offered by this prospectus should consult their tax advisors regarding the U.S. federal income and other tax consequences to them of the acquisition, ownership and disposition of such securities.

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PLAN OF DISTRIBUTION

We may sell the offered securities from time to time:

• through underwriters or dealers;

• through agents;

• directly to one or more purchasers; or

• through a combination of any of these methods of sale.

We will identify the specific plan of distribution, including any underwriters, dealers, agents or direct purchasers and their compensation in the applicable prospectus supplement.

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LEGAL MATTERS

Certain legal matters will be passed upon for us by Latham & Watkins LLP, San Diego, California. Venable LLP, Baltimore, Maryland, has issued an opinion to us regarding certain matters of Maryland law, including the validity of the securities offered hereby. Additional legal matters may be passed upon for us or any underwriters, dealers or agents, by counsel that we will name in the applicable prospectus supplement.

EXPERTS

The consolidated financial statements of American Assets Trust, Inc. and American Assets Trust, L.P. appearing in American Assets Trust, Inc.’s and American Assets Trust, L.P.’s Annual Report (Form 10-K) for the year ended December 31, 2019, including the schedule appearing therein, and the effectiveness of American Assets Trust, Inc.’s internal control over financial reporting as of December 31, 2019 have been audited by Ernst & Young LLP, independent registered public accounting firm, as set forth in their reports thereon, included therein, and incorporated herein by reference. Such consolidated financial statements and American Assets Trust, Inc.’s management’s assessment of the effectiveness of internal control over financial reporting as of December 31, 2019 are incorporated herein by reference in reliance upon such reports given on the authority of such firm as experts in accounting and auditing.

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