Edgar Filing: Western Asset Investment Grade Defined Opportunity Trust Inc.

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM N-CSR

CERTIFIED SHAREHOLDER REPORT OF REGISTERED
MANAGEMENT INVESTMENT COMPANIES

Investment Company Act file number			811-22294

Western Asset Investment Grade Defined Opportunity Trust Inc.
(Exact name of registrant as specified in charter)

620 Eighth Avenue, 49th Floor New York, NY					10018
(Address of principal executive offices)					(Zip code)

Robert I. Frenkel, Esq. Legg Mason & Co., LLC 100 First Stamford Place Stamford, CT 06902
(Name and address of agent for service)

Registrant’s telephone number, including area code:				(888)777-0102

Date of fiscal year end:	November 30

Date of reporting period:		May 31, 2012

ITEM 1. REPORT TO STOCKHOLDERS.

The Semi-Annual Report to Stockholders is filed herewith.

May 31, 2012

Semi-Annual Report

Western Asset Investment Grade Defined Opportunity Trust Inc.
(IGI)

INVESTMENT PRODUCTS: NOT FDIC INSURED · NO BANK GUARANTEE · MAY LOSE VALUE

Western Asset Investment Grade Defined Opportunity Trust Inc.

Fund objectives

The Fund’s primary investment objective is to provide current income and then to liquidate and distribute substantially all of the Fund’s net assets to stockholders on or about December 2, 2024. As a secondary investment objective, the Fund will seek capital appreciation. There can be no assurance the Fund will achieve its investment objectives.

What’s inside

Letter from the chairman	II

Investment commentary	III

Fund at a glance	1

Spread duration	2

Effective duration	3

Schedule of investments	4

Statement of assets and liabilities	15

Statement of operations	16

Statements of changes in net assets	17

Financial highlights	18

Notes to financial statements	19

Additional shareholder information	32

Dividend reinvestment plan	33

Letter from the chairman

Dear Shareholder,

We are pleased to provide the semi-annual report of Western Asset Investment Grade Defined Opportunity Trust Inc. for the six-month reporting period ended May 31, 2012. Please read on for Fund performance information and a detailed look at prevailing economic and market conditions during the Fund’s reporting period.

As always, we remain committed to providing you with excellent service and a full spectrum of investment choices. We also remain committed to supplementing the support you receive from your financial advisor. One way we accomplish this is through our website, www.lmcef.com. Here you can gain immediate access to market and investment information, including:

· Fund prices and performance,

· Market insights and commentaries from our portfolio managers, and

· A host of educational resources.

We look forward to helping you meet your financial goals.

Sincerely,

R. Jay Gerken, CFA

Chairman, President and Chief Executive Officer

June 29, 2012

Western Asset Investment Grade Defined Opportunity Trust Inc.

III

Investment commentary

Economic review

The U.S. economy continued to grow over the six months ended May 31, 2012, albeit at an uneven pace. Looking back, U.S. gross domestic product (“GDP”)i growth, as reported by the U.S. Department of Commerce, was 1.8% in the third quarter of 2011. The economy then gathered some momentum late in 2011, as the Commerce Department reported that fourth quarter GDP growth was 3.0% — the fastest pace since the second quarter of 2010. However, economic growth in the U.S. then moderated somewhat, as the Commerce Department reported that first quarter 2012 GDP growth was 1.9%.

Two factors constraining economic growth were the weak job market and continued troubles in the housing market. While there was some improvement during the reporting period, unemployment remained elevated. When the reporting period began, unemployment, as reported by the U.S. Department of Labor, was 8.7%. Unemployment then generally declined over the next five months and was 8.1% in April 2012, the lowest rate since January 2009. However, the unemployment rate then moved up to 8.2% in May 2012. The housing market showed some positive signs, although it still appears to be searching for a bottom. According to the National Association of Realtors (“NAR”), existing-home sales fluctuated throughout the period. Existing-home sales fell 1.5% on a seasonally adjusted basis in May 2012 versus the previous month. However, the NAR reported that the median existing-home price for all housing types was $182,600 in May 2012, up 7.9% from May 2011. In addition, the inventory of unsold homes fell 0.4% in May versus the previous month.

The manufacturing sector overcame a soft patch in the summer of 2011 and continued to expand during the reporting period. Based on the Institute for Supply Management’s PMI (“PMI”)ii, in August 2011, it had a reading of 50.6, its lowest reading in two years (a reading below 50 indicates a contraction, whereas a reading above 50 indicates an expansion). The manufacturing sector gathered momentum and ended January 2012 at 54.1, its highest reading since June 2011. After falling to 52.4 in February, the PMI rose to 53.4 in March and 54.8 in April. The PMI then dipped to 53.5 in May 2012.

Western Asset Investment Grade Defined Opportunity Trust Inc.

Investment commentary (cont’d)

Market review

Q. Did Treasury yields trend higher or lower during the six months ended May 31, 2012?

A. Both short- and long-term Treasury yields fluctuated during the reporting period. When the period began, two- and ten-year Treasury yields were 0.25% and 2.08%, respectively. With the economy initially gathering some momentum, Treasury yields moved higher during the first half of the period. Two-year Treasury yields rose as high as 0.41% on March 20, 2012 and ten-year Treasuries peaked at 2.39% around the same time. Yields then fell in late March, as well as in April and May given renewed fears over the European sovereign debt crisis. When the reporting period ended on May 31, 2012, two-year Treasury yields were 0.27% and ten-year Treasury yields were 1.59%, the latter being a historic low.

Q. How did the Federal Reserve Board (“Fed”)iii respond to the economic environment?

A. The Fed took a number of actions as it sought to meet its dual mandate of fostering maximum employment and price stability. As has been the case since December 2008, the Fed kept the federal funds rateiv at a historically low range between zero and 0.25%. In August 2011, the Fed declared its intention to keep the federal funds rate steady until mid-2013. Then, in September 2011, the Fed announced its intention to purchase $400 billion of longer-term Treasury securities and to sell an equal amount of shorter-term Treasury securities by June 2012 (often referred to as “Operation Twist”). In January 2012, the Fed extended the period it expects to keep rates on hold, saying “economic conditions — including low rates of resource utilization and a subdued outlook for inflation over the medium run — are likely to warrant exceptionally low levels for the federal funds rate at least through late 2014.” In June, after the reporting period ended, the Fed announced that it would extend Operation Twist until the end of 2012 and that it was “prepared to take further action as appropriate to promote a stronger economic recovery and sustained improvement in labor market conditions in a context of price stability.”

Q. What factors impacted the spread sectors (non-Treasuries) during the reporting period?

A. The spread sectors experienced periods of volatility during the period. Risk appetite was often robust over the first three months of the period, due to some better-than-expected economic data and signs of progress in the European sovereign debt crisis. However, fears related to the situation in Europe caused a number of spread sectors to weaken in April. While the spread sectors posted positive absolute returns in April, they generally lagged equal-durationv Treasuries. Several of the riskiest spread sectors then performed poorly in May given a flight to quality that was triggered by escalating fears of contagion from Europe and some disappointing economic data in the U.S. For the six months ended May 31, 2012, the Barclays Capital U.S. Aggregate Indexvi returned 3.46%.

Q. How did the high-yield market perform over the six months ended May 31, 2012?

A. Despite a setback in May 2012, the U.S. high-yield bond market generated a strong return during the reporting period. The asset class, as measured by the Barclays Capital U.S. High Yield — 2% Issuer Cap Indexvii, rallied during four of the first five months of the period. Risk appetite was often solid during

Western Asset Investment Grade Defined Opportunity Trust Inc.

this period as investors looked to generate incremental yield in the low interest rate environment. However, the high-yield market faltered in May as risk aversion increased due to several macro issues that negatively impacted investor sentiment. All told, the high-yield market gained 7.81% for the six months ended May 31, 2012.

Q. How did the emerging market debt asset class perform over the reporting period?

A. After a strong start, the asset class gave back a portion of its gains late in the reporting period. During the first five months of the period, emerging market debt was supported by solid growth in developing countries and overall solid demand. However, a confluence of events, including the European sovereign debt crisis, moderating growth in the U.S. and fears that China’s economy would experience a hard landing, caused the asset class to fall sharply in May 2012. Overall, the JPMorgan Emerging Markets Bond Index Global (“EMBI Global”)viii returned 4.97% over the six months ended May 31, 2012.

Performance review

For the six months ended May 31, 2012, Western Asset Investment Grade Defined Opportunity Trust Inc. returned 7.95% based on its net asset value (“NAV”)ix and 10.06% based on its New York Stock Exchange (“NYSE”) market price per share. The Fund’s unmanaged benchmark, the Barclays Capital U.S. Credit Indexx, returned 6.13% for the same period. The Lipper Corporate Debt BBB-Rated Closed-End Funds Category Averagexi returned 7.23% over the same time frame. Please note that Lipper performance returns are based on each fund’s NAV.

During this six-month period, the Fund made distributions to shareholders totaling $0.77 per share, which may have included a return of capital. The performance table shows the Fund’s six-month total return based on its NAV and market price as of May 31, 2012. Past performance is no guarantee of future results.

Performance Snapshot as of May 31, 2012 (unaudited)

Price Per Share		6-Month Total Return*
$21.49 (NAV)		7.95%†
$22.87 (Market Price)		10.06%‡

All figures represent past performance and are not a guarantee of future results. Performance figures for periods shorter than one year represent cumulative figures and are not annualized.

* Total returns are based on changes in NAV or market price, respectively.

† Total return assumes the reinvestment of all distributions, including returns of capital, if any, at NAV. Prior to January 1, 2012, total return assumed the reinvestment of all distributions in additional shares in accordance with the Fund’s Dividend Reinvestment Plan.

‡ Total return assumes the reinvestment of all distributions, including returns of capital, if any, in additional shares in accordance with the Fund’s Dividend Reinvestment Plan.

Looking for additional information?

The Fund is traded under the symbol “IGI” and its closing market price is available in most newspapers under the NYSE listings. The daily NAV is available on-line under the symbol “XIGIX” on most financial websites. Barron’s and the Wall Street Journal’s Monday edition both carry closed-end fund

Western Asset Investment Grade Defined Opportunity Trust Inc.

Investment commentary (cont’d)

tables that provide additional information. In addition, the Fund issues a quarterly press release that can be found on most major financial websites as well as www.lmcef.com.

In a continuing effort to provide information concerning the Fund, shareholders may call 1-888-777-0102 (toll free), Monday through Friday from 8:00 a.m. to 5:30 p.m. Eastern Time, for the Fund’s current NAV, market price and other information.

As always, thank you for your confidence in our stewardship of your assets.

Sincerely,

R. Jay Gerken, CFA

Chairman, President and Chief Executive Officer

June 29, 2012

RISKS: The Fund’s investments are subject to credit risk, inflation risk and interest rate risk. As interest rates rise, bond prices fall, reducing the value of the Fund’s holdings. The Fund may invest in lower-rated high-yield bonds which are subject to greater credit risk (risk of default) than higher-rated obligations. The Fund may use derivatives, such as options and futures, which can be illiquid, may disproportionately increase losses and have a potentially large impact on Fund performance. The Fund may invest in securities or engage in transactions that have the economic effects of leverage which can increase the risk and volatility of the Fund.

All investments are subject to risk including the possible loss of principal. Past performance is no guarantee of future results. All index performance reflects no deduction for fees, expenses or taxes. Please note that an investor cannot invest directly in an index.

The information provided is not intended to be a forecast of future events, a guarantee of future results or investment advice. Views expressed may differ from those of the firm as a whole.

Western Asset Investment Grade Defined Opportunity Trust Inc.

VII

i		Gross domestic product (“GDP”) is the market value of all final goods and services produced within a country in a given period of time.
ii		The Institute for Supply Management’s PMI is based on a survey of purchasing executives who buy the raw materials for manufacturing at more than 350 companies. It offers an early reading on the health of the manufacturing sector.
iii		The Federal Reserve Board (“Fed”) is responsible for the formulation of policies designed to promote economic growth, full employment, stable prices and a sustainable pattern of international trade and payments.
iv		The federal funds rate is the rate charged by one depository institution on an overnight sale of immediately available funds (balances at the Federal Reserve) to another depository institution; the rate may vary from depository institution to depository institution and from day to day.
v		Duration is the measure of the price sensitivity of a fixed-income security to an interest rate change of 100 basis points. Calculation is based on the weighted average of the present values for all cash flows.
vi		The Barclays Capital U.S. Aggregate Index is a broad-based bond index comprised of government, corporate, mortgage- and asset-backed issues, rated investment grade or higher, and having at least one year to maturity.
vii		The Barclays Capital U.S. High Yield — 2% Issuer Cap Index is an index of the 2% Issuer Cap component of the Barclays Capital U.S. Corporate High Yield Index, which covers the U.S. dollar-denominated, non-investment grade, fixed-rate, taxable corporate bond market.
viii		The JPMorgan Emerging Markets Bond Index Global (“EMBI Global”) tracks total returns for U.S. dollar-denominated debt instruments issued by emerging market sovereign and quasi-sovereign entities: Brady bonds, loans, Eurobonds and local market instruments.
ix		Net asset value (“NAV”) is calculated by subtracting total liabilities and outstanding preferred stock (if any) from the closing value of all securities held by the Fund (plus all other assets) and dividing the result (total net assets) by the total number of the common shares outstanding. The NAV fluctuates with changes in the market prices of securities in which the Fund has invested. However, the price at which an investor may buy or sell shares of the Fund is the Fund’s market price as determined by supply of and demand for the Fund’s shares.
x		The Barclays Capital U.S. Credit Index is an index composed of corporate and non-corporate debt issues that are investment grade (rated Baa3/BBB or higher).
xi		Lipper, Inc., a wholly-owned subsidiary of Reuters, provides independent insight on global collective investments. Returns are based on the six-month period ended May 31, 2012, including the reinvestment of all distributions, including returns of capital, if any, calculated among the 27 funds in the Fund’s Lipper category.

Western Asset Investment Grade Defined Opportunity Trust Inc. 2012 Semi-Annual Report

Fund at a glance† (unaudited)

Investment breakdown (%) as a percent of total investments

† The bar graph above represents the composition of the Fund’s investments as of May 31, 2012 and November 30, 2011 and does not include derivatives, such as futures contracts, swap contracts and forward foreign currency contracts. The Fund is actively managed. As a result, the composition of the Fund’s investments is subject to change at any time.

Western Asset Investment Grade Defined Opportunity Trust Inc. 2012 Semi-Annual Report

Spread duration (unaudited)

Economic Exposure — May 31, 2012

Spread duration measures the sensitivity to changes in spreads. The spread over Treasuries is the annual risk-premium demanded by investors to hold non-Treasury securities. Spread duration is quantified as the % change in price resulting from a 100 basis points change in spreads. For a security with positive spread duration, an increase in spreads would result in a price decline and a decline in spreads would result in a price increase. This chart highlights the market sector exposure of the Fund’s sectors relative to the selected benchmark sectors as of the end of the reporting period.

______________________

BC U.S. Credit	— Barclays Capital U.S. Credit Index
EM	— Emerging Markets
HY	— High Yield
IG Credit	— Investment Grade Credit
IGI	— Western Asset Investment Grade Defined Opportunity Trust Inc.

Western Asset Investment Grade Defined Opportunity Trust Inc. 2012 Semi-Annual Report

Effective duration (unaudited)

Interest Rate Exposure — May 31, 2012

Effective duration measures the sensitivity to changes in relevant interest rates. Effective duration is quantified as the % change in price resulting from a 100 basis points change in interest rates. For a security with positive effective duration, an increase in interest rates would result in a price decline and a decline in interest rates would result in a price increase. This chart highlights the interest rate exposure of the Fund’s sectors relative to the selected benchmark sectors as of the end of the reporting period.

______________________

BC U.S. Credit	— Barclays Capital U.S. Credit Index
EM	— Emerging Markets
HY	— High Yield
IG Credit	— Investment Grade Credit
IGI	— Western Asset Investment Grade Defined Opportunity Trust Inc.

Western Asset Investment Grade Defined Opportunity Trust Inc. 2012 Semi-Annual Report

Schedule of investments (unaudited)

May 31, 2012

Western Asset Investment Grade Defined Opportunity Trust Inc.

Security	Rate		Maturity Date	Face Amount	Value
Corporate Bonds & Notes — 92.6%
Consumer Discretionary — 9.0%
*Automobiles — 0.5%*
Ford Motor Credit Co., LLC, Senior Notes	12.000	%	5/15/15	$1,000,000	$ 1,270,000
*Hotels, Restaurants & Leisure — 0.9%*
Caesars Entertainment Operating Co. Inc., Senior Secured Notes	11.250	%	6/1/17	1,250,000	1,334,375
NCL Corp. Ltd., Senior Secured Notes	11.750	%	11/15/16	320,000	369,600
Wynn Las Vegas LLC/Wynn Las Vegas Capital Corp., Senior Secured Notes	5.375	%	3/15/22	420,000	407,925	(a)
*Total Hotels, Restaurants & Leisure*					*2,111,900*
*Household Durables — 0.1%*
Whirlpool Corp., Senior Notes	4.700	%	6/1/22	260,000	*261,958*
*Media — 6.3%*
Comcast Corp., Bonds	6.400	%	5/15/38	2,500,000	3,084,663
Comcast Corp., Senior Notes	5.700	%	7/1/19	1,500,000	1,789,512
DISH DBS Corp., Senior Notes	7.875	%	9/1/19	1,250,000	1,396,875
News America Inc., Senior Notes	6.650	%	11/15/37	2,400,000	2,774,806
Nielsen Finance LLC/Nielsen Finance Co., Senior Notes	11.500	%	5/1/16	340,000	385,900
Time Warner Cable Inc., Debentures	7.300	%	7/1/38	500,000	638,554
Time Warner Cable Inc., Senior Notes	8.750	%	2/14/19	1,100,000	1,459,186
United Business Media Ltd., Notes	5.750	%	11/3/20	830,000	855,891	(a)
WPP Finance 2010, Senior Notes	4.750	%	11/21/21	870,000	917,106	(a)
WPP Finance UK, Senior Notes	8.000	%	9/15/14	1,000,000	1,136,004
*Total Media*					*14,438,497*
*Specialty Retail — 0.7%*
American Greetings Corp., Senior Notes	7.375	%	12/1/21	280,000	292,600
Gap Inc., Senior Notes	5.950	%	4/12/21	1,240,000	1,282,544
*Total Specialty Retail*					*1,575,144*
*Textiles, Apparel & Luxury Goods — 0.5%*
Oxford Industries Inc., Senior Secured Notes	11.375	%	7/15/15	1,000,000	*1,068,760*
Total Consumer Discretionary					20,726,259
Consumer Staples — 6.3%
*Beverages — 1.4%*
Anheuser-Busch InBev Worldwide Inc., Senior Notes	7.750	%	1/15/19	450,000	596,189
Molson Coors Brewing Co., Senior Notes	3.500	%	5/1/22	690,000	704,791
Pernod-Ricard SA, Senior Bonds	5.750	%	4/7/21	890,000	1,006,720	(a)
Pernod-Ricard SA, Senior Notes	5.500	%	1/15/42	960,000	989,634	(a)
*Total Beverages*					*3,297,334*

See Notes to Financial Statements.

Western Asset Investment Grade Defined Opportunity Trust Inc. 2012 Semi-Annual Report

Western Asset Investment Grade Defined Opportunity Trust Inc.

Security	Rate		Maturity Date	Face Amount	Value
*Food & Staples Retailing — 0.3%*
CVS Caremark Corp., Senior Notes	6.600	%	3/15/19	$ 600,000	$ 757,810
*Food Products — 1.6%*
Kraft Foods Group Inc., Senior Notes	3.500	%	6/6/22	550,000	563,316	(a)
Kraft Foods Group Inc., Senior Notes	5.000	%	6/4/42	860,000	896,730	(a)
Kraft Foods Inc., Senior Notes	5.375	%	2/10/20	1,030,000	1,219,531
Smithfield Foods Inc., Senior Secured Notes	10.000	%	7/15/14	801,000	925,155
*Total Food Products*					*3,604,732*
*Tobacco — 3.0%*
Altria Group Inc., Senior Notes	9.250	%	8/6/19	1,000,000	1,375,883
Lorillard Tobacco Co., Senior Notes	8.125	%	6/23/19	540,000	674,331
Lorillard Tobacco Co., Senior Notes	8.125	%	5/1/40	470,000	586,229
Lorillard Tobacco Co., Senior Notes	7.000	%	8/4/41	510,000	575,028
Philip Morris International Inc., Senior Notes	4.500	%	3/20/42	1,140,000	1,248,751
Reynolds American Inc., Senior Secured Notes	7.625	%	6/1/16	2,000,000	2,416,856
*Total Tobacco*					*6,877,078*
Total Consumer Staples					14,536,954
Energy — 13.2%
*Oil, Gas & Consumable Fuels — 13.2%*
Anadarko Petroleum Corp., Senior Notes	5.950	%	9/15/16	340,000	385,889
Apache Corp., Senior Notes	5.100	%	9/1/40	140,000	159,905
Apache Corp., Senior Notes	5.250	%	2/1/42	160,000	187,061
Arch Coal Inc., Senior Notes	7.000	%	6/15/19	440,000	379,500	(a)
ConocoPhillips, Notes	6.500	%	2/1/39	1,500,000	2,067,522
DCP Midstream LLC, Senior Notes	9.750	%	3/15/19	1,000,000	1,306,717	(a)
DCP Midstream Partners LP, Senior Notes	4.950	%	4/1/22	900,000	927,812
Devon Energy Corp., Senior Notes	3.250	%	5/15/22	20,000	20,325
Devon Financing Corp. ULC, Debentures	7.875	%	9/30/31	1,080,000	1,544,913
Enterprise Products Operating LP, Senior Notes	9.750	%	1/31/14	2,000,000	2,270,378
EOG Resources Inc., Senior Notes	6.875	%	10/1/18	800,000	1,011,756
Hess Corp., Notes	8.125	%	2/15/19	1,400,000	1,821,764
Hess Corp., Notes	7.875	%	10/1/29	440,000	582,828
Hess Corp., Senior Bonds	6.000	%	1/15/40	520,000	589,558
Kerr-McGee Corp., Notes	6.950	%	7/1/24	1,320,000	1,641,737
Kerr-McGee Corp., Notes	7.875	%	9/15/31	830,000	1,069,161
Kinder Morgan Energy Partners LP, Senior Notes	5.950	%	2/15/18	800,000	933,360
Noble Energy Inc., Senior Notes	6.000	%	3/1/41	660,000	755,363
Pemex Project Funding Master Trust, Senior Bonds	6.625	%	6/15/35	1,000,000	1,147,500
Petrobras International Finance Co., Senior Notes	5.750	%	1/20/20	1,109,000	1,213,572
Petrobras International Finance Co., Senior Notes	6.750	%	1/27/41	2,490,000	2,882,058

See Notes to Financial Statements.

Western Asset Investment Grade Defined Opportunity Trust Inc. 2012 Semi-Annual Report

Schedule of investments (unaudited) (cont’d)

May 31, 2012

Western Asset Investment Grade Defined Opportunity Trust Inc.

Security	Rate		Maturity Date	Face Amount	Value
*Oil, Gas & Consumable Fuels — continued*
Petroleos Mexicanos, Senior Notes	5.500	%	1/21/21	$ 250,000	$ 276,250
Phillips 66, Senior Notes	5.875	%	5/1/42	260,000	278,486	(a)
Quicksilver Resources Inc., Senior Notes	11.750	%	1/1/16	1,000,000	1,030,000
Shell International Finance BV, Senior Notes	6.375	%	12/15/38	1,500,000	2,081,599
TNK-BP Finance SA, Senior Notes	7.500	%	3/13/13	870,000	908,063	(a)
Transcontinental Gas Pipe Line Co. LLC, Senior Notes	5.400	%	8/15/41	10,000	11,741
Valero Energy Corp., Senior Notes	9.375	%	3/15/19	700,000	927,491
Williams Cos. Inc., Notes	7.875	%	9/1/21	952,000	1,238,379
Williams Cos. Inc., Senior Notes	7.750	%	6/15/31	62,000	78,741
Williams Cos. Inc., Senior Notes	8.750	%	3/15/32	148,000	206,834
Williams Partners LP, Senior Notes	5.250	%	3/15/20	460,000	520,898
Total Energy					30,457,161
Financials — 32.8%
*Capital Markets — 8.1%*
Bear Stearns Cos. LLC, Senior Notes	7.250	%	2/1/18	1,570,000	1,853,283
Credit Suisse New York, Senior Notes	5.300	%	8/13/19	560,000	627,894
GFI Group Inc., Senior Notes	8.375	%	7/19/18	810,000	716,850
Goldman Sachs Group Inc., Senior Notes	5.950	%	1/18/18	4,250,000	4,444,344
Goldman Sachs Group Inc., Senior Notes	7.500	%	2/15/19	500,000	568,648
Goldman Sachs Group Inc., Senior Notes	5.375	%	3/15/20	470,000	478,930
Goldman Sachs Group Inc., Senior Notes	5.250	%	7/27/21	870,000	862,162
Goldman Sachs Group Inc., Senior Notes	6.250	%	2/1/41	2,550,000	2,576,321
Merrill Lynch & Co. Inc., Notes	6.875	%	4/25/18	990,000	1,089,171
Morgan Stanley, Medium-Term Notes	6.625	%	4/1/18	1,750,000	1,778,436
Morgan Stanley, Senior Notes	5.500	%	1/26/20	1,950,000	1,835,510
Morgan Stanley, Senior Notes	5.500	%	7/24/20	200,000	187,678
State Street Corp., Junior Subordinated Notes	4.956	%	3/15/18	1,330,000	1,393,191
UBS AG Stamford CT, Senior Notes	4.875	%	8/4/20	250,000	263,758
*Total Capital Markets*					*18,676,176*
*Commercial Banks — 6.0%*
BankAmerica Institutional Capital A, Junior Subordinated Bonds	8.070	%	12/31/26	240,000	242,400	(a)
BankAmerica Institutional Capital B, Junior Subordinated Bonds	7.700	%	12/31/26	250,000	251,875	(a)
CIT Group Inc., Secured Notes	5.250	%	4/1/14	630,000	644,175	(a)
CIT Group Inc., Secured Notes	6.625	%	4/1/18	480,000	501,600	(a)
Cooperatieve Centrale Raiffeisen-Boerenleenbank BA, Senior Notes	5.250	%	5/24/41	310,000	335,175
Intesa Sanpaolo SpA, Senior Notes	3.625	%	8/12/15	2,020,000	1,739,267	(a)

See Notes to Financial Statements.

Western Asset Investment Grade Defined Opportunity Trust Inc. 2012 Semi-Annual Report

Western Asset Investment Grade Defined Opportunity Trust Inc.

Security	Rate		Maturity Date	Face Amount	Value
*Commercial Banks — continued*
Intesa Sanpaolo SpA, Senior Notes	6.500	%	2/24/21	$ 330,000	$ 286,117	(a)
Lloyds TSB Bank PLC, Senior Notes	4.200	%	3/28/17	610,000	609,837
Lloyds TSB Bank PLC, Senior Notes	6.375	%	1/21/21	80,000	86,434
NB Capital Trust IV, Junior Subordinated Notes	8.250	%	4/15/27	1,030,000	1,039,991
Royal Bank of Scotland Group PLC, Junior Subordinated Bonds	7.648	%	9/30/31	680,000	525,300	(b)(c)
Royal Bank of Scotland Group PLC, Senior Notes	6.400	%	10/21/19	1,170,000	1,211,200
Royal Bank of Scotland Group PLC, Subordinated Notes	5.000	%	10/1/14	990,000	969,984
Wachovia Capital Trust III, Junior Subordinated Bonds	5.570	%	7/16/12	270,000	252,113	(b)(c)
Wachovia Corp., Senior Notes	5.750	%	2/1/18	4,400,000	5,103,080
*Total Commercial Banks*					*13,798,548*
*Consumer Finance — 3.7%*
Ally Financial Inc., Senior Notes	8.000	%	3/15/20	1,500,000	1,698,750
American Express Co., Senior Notes	8.125	%	5/20/19	2,760,000	3,686,405
HSBC Finance Corp., Senior Notes	6.676	%	1/15/21	1,620,000	1,750,893
SLM Corp., Senior Notes	7.250	%	1/25/22	1,430,000	1,406,811
*Total Consumer Finance*					*8,542,859*
*Diversified Financial Services — 10.8%*
Bank of America Corp., Senior Notes	7.625	%	6/1/19	2,760,000	3,159,295
Bank of America Corp., Senior Notes	5.625	%	7/1/20	180,000	186,724
Bank of America Corp., Senior Notes	5.875	%	2/7/42	2,380,000	2,438,369
Citigroup Inc., Senior Notes	6.375	%	8/12/14	300,000	321,906
Citigroup Inc., Senior Notes	6.000	%	8/15/17	2,250,000	2,442,004
Citigroup Inc., Senior Notes	8.500	%	5/22/19	500,000	613,219
Citigroup Inc., Senior Notes	6.875	%	3/5/38	2,000,000	2,353,864
Citigroup Inc., Senior Notes	8.125	%	7/15/39	1,350,000	1,796,290
Citigroup Inc., Senior Notes	5.875	%	1/30/42	410,000	437,840
General Electric Capital Corp., Notes	5.300	%	2/11/21	890,000	992,434
General Electric Capital Corp., Senior Notes	6.000	%	8/7/19	790,000	928,782
General Electric Capital Corp., Senior Notes	6.875	%	1/10/39	3,010,000	3,865,770
ILFC E-Capital Trust I	5.030	%	12/21/65	370,000	251,156	(a)(b)
International Lease Finance Corp., Senior Notes	8.875	%	9/1/17	810,000	909,225
International Lease Finance Corp., Senior Notes	6.250	%	5/15/19	220,000	220,055
International Lease Finance Corp., Senior Notes	8.250	%	12/15/20	330,000	368,775
International Lease Finance Corp., Senior Secured Notes	6.750	%	9/1/16	670,000	721,925	(a)
International Lease Finance Corp., Senior Secured Notes	7.125	%	9/1/18	1,030,000	1,138,150	(a)

See Notes to Financial Statements.

Western Asset Investment Grade Defined Opportunity Trust Inc. 2012 Semi-Annual Report

Schedule of investments (unaudited) (cont’d)

May 31, 2012

Western Asset Investment Grade Defined Opportunity Trust Inc.

Security	Rate		Maturity Date	Face Amount	Value
*Diversified Financial Services — continued*
JPMorgan Chase & Co., Senior Notes	6.400	%	5/15/38	$1,500,000	$ 1,768,611
*Total Diversified Financial Services*					*24,914,394*
*Insurance — 3.5%*
American International Group Inc., Senior Notes	4.875	%	9/15/16	600,000	633,337
American International Group Inc., Senior Notes	6.400	%	12/15/20	1,000,000	1,123,900
Berkshire Hathaway Finance Corp., Senior Notes	4.400	%	5/15/42	250,000	252,411
Delphi Financial Group Inc., Senior Notes	7.875	%	1/31/20	290,000	346,422
ING Capital Funding Trust III, Junior Subordinated Bonds	4.070	%	9/30/12	410,000	340,520	(b)(c)
MetLife Inc., Senior Notes	6.817	%	8/15/18	1,300,000	1,578,939
Mitsui Sumitomo Insurance Co., Ltd., Notes	7.000	%	3/15/72	1,110,000	1,147,839	(a)(b)
Nationwide Mutual Insurance Co., Notes	9.375	%	8/15/39	520,000	687,507	(a)
Teachers Insurance & Annuity Association of America — College Retirement Equity Fund, Notes	6.850	%	12/16/39	1,050,000	1,382,387	(a)
Travelers Cos. Inc., Senior Notes	6.250	%	6/15/37	400,000	526,841
*Total Insurance*					*8,020,103*
*Real Estate Investment Trusts (REITs) — 0.6%*
Boston Properties LP, Senior Notes	3.850	%	2/1/23	520,000	518,851
WEA Finance LLC/WT Finance Aust Pty. Ltd., Senior Notes	6.750	%	9/2/19	580,000	691,234	(a)
*Total Real Estate Investment Trusts (REITs)*					*1,210,085*
*Thrifts & Mortgage Finance — 0.1%*
Santander Holdings USA Inc., Senior Notes	4.625	%	4/19/16	270,000	*263,081*
Total Financials					75,425,246
Health Care — 5.2%
*Biotechnology — 0.7%*
Amgen Inc., Senior Notes	5.150	%	11/15/41	1,020,000	1,055,929
Gilead Sciences Inc., Senior Notes	5.650	%	12/1/41	480,000	558,368
*Total Biotechnology*					*1,614,297*
*Health Care Equipment & Supplies — 0.5%*
Biomet Inc., Senior Toggle Notes	10.375	%	10/15/17	1,000,000	*1,069,375*	(d)
*Health Care Providers & Services — 3.0%*
CIGNA Corp., Senior Notes	4.500	%	3/15/21	470,000	511,349
Highmark Inc., Senior Notes	4.750	%	5/15/21	570,000	592,947	(a)
Humana Inc., Senior Notes	6.450	%	6/1/16	1,000,000	1,138,673
Humana Inc., Senior Notes	7.200	%	6/15/18	1,000,000	1,211,894
InVentiv Health Inc., Senior Notes	10.000	%	8/15/18	580,000	493,000	(a)
Tenet Healthcare Corp., Senior Secured Notes	10.000	%	5/1/18	1,000,000	1,145,000
Tenet Healthcare Corp., Senior Secured Notes	8.875	%	7/1/19	430,000	480,525

See Notes to Financial Statements.

Western Asset Investment Grade Defined Opportunity Trust Inc. 2012 Semi-Annual Report

Western Asset Investment Grade Defined Opportunity Trust Inc.

Security	Rate		Maturity Date	Face Amount	Value
*Health Care Providers & Services — continued*
WellPoint Inc., Notes	5.250	%	1/15/16	$1,200,000	$ 1,345,212
*Total Health Care Providers & Services*					*6,918,600*
*Pharmaceuticals — 1.0%*
Pfizer Inc., Senior Notes	7.200	%	3/15/39	560,000	855,059
Wyeth, Notes	5.950	%	4/1/37	1,100,000	1,451,825
*Total Pharmaceuticals*					*2,306,884*
Total Health Care					11,909,156
Industrials — 5.1%
*Aerospace & Defense — 0.5%*
Exelis Inc., Senior Notes	5.550	%	10/1/21	885,000	961,024	(a)
L-3 Communications Corp., Senior Subordinated Notes	6.375	%	10/15/15	217,000	222,425
*Total Aerospace & Defense*					*1,183,449*
*Air Freight & Logistics — 0.4%*
United Parcel Service Inc., Senior Notes	6.200	%	1/15/38	700,000	*960,396*
*Airlines — 2.2%*
Continental Airlines Inc., Pass-Through Certificates	9.250	%	5/10/17	344,073	377,190
Continental Airlines Inc., Pass-Through Certificates	6.545	%	2/2/19	226,989	243,446
Continental Airlines Inc., Pass-Through Certificates, Senior Secured Notes	7.250	%	11/10/19	730,414	821,716
Continental Airlines Inc., Secured Notes	6.250	%	10/22/21	290,000	296,163
Delta Air Lines, Pass-Through Trust, Senior Secured Notes	7.750	%	2/17/19	728,114	831,870
Delta Air Lines Inc., Pass-Through Certificates, Secured Notes	8.021	%	8/10/22	190,229	194,033
United Air Lines Inc., Senior Secured Notes	9.875	%	8/1/13	427,000	441,945	(a)
United Air Lines Inc., Senior Secured Notes	12.000	%	11/1/13	570,000	602,062	(a)
United Airlines, Pass-Through Trust, Pass-Through Certificates, Secured Notes	9.750	%	1/15/17	208,722	238,986
United Airlines, Pass-Through Trust, Senior Secured Notes	10.400	%	11/1/16	160,170	183,394
US Airways 2012-1 Pass-Through Trust, Senior Secured Bonds	5.900	%	4/1/26	890,000	904,462
*Total Airlines*					*5,135,267*
*Commercial Services & Supplies — 0.1%*
Republic Services Inc., Senior Notes	5.500	%	9/15/19	220,000	*256,883*
*Electrical Equipment — 0.3%*
ABB Finance U.S.A. Inc., Senior Notes	4.375	%	5/8/42	720,000	*746,086*

See Notes to Financial Statements.

Western Asset Investment Grade Defined Opportunity Trust Inc. 2012 Semi-Annual Report

Schedule of investments (unaudited) (cont’d)

May 31, 2012

Western Asset Investment Grade Defined Opportunity Trust Inc.

Security	Rate		Maturity Date	Face Amount	Value
*Industrial Conglomerates — 0.7%*
United Technologies Corp., Senior Notes	4.500	%	6/1/42	$1,480,000	$ 1,591,798
*Machinery — 0.1%*
Valmont Industries Inc., Senior Notes	6.625	%	4/20/20	180,000	*214,792*
*Road & Rail — 0.8%*
Burlington Northern Santa Fe LLC, Senior Notes	4.400	%	3/15/42	1,010,000	1,016,233
Kansas City Southern de Mexico, Senior Notes	12.500	%	4/1/16	650,000	741,000
*Total Road & Rail*					*1,757,233*
Total Industrials					11,845,904
Information Technology — 0.4%
*IT Services — 0.2%*
Mantech International Corp., Senior Notes	7.250	%	4/15/18	540,000	*572,400*
*Semiconductors & Semiconductor Equipment — 0.2%*
National Semiconductor Corp., Senior Notes	6.600	%	6/15/17	360,000	*447,902*
Total Information Technology					1,020,302
Materials — 6.2%
*Chemicals — 0.7%*
Eastman Chemical Co., Senior Notes	4.800	%	9/1/42	500,000	496,585
Ecolab Inc., Senior Notes	5.500	%	12/8/41	260,000	304,511
Potash Corp. of Saskatchewan Inc., Senior Notes	5.625	%	12/1/40	530,000	671,183
*Total Chemicals*					*1,472,279*
*Containers & Packaging — 0.7%*
Rock-Tenn Co., Senior Notes	4.450	%	3/1/19	810,000	829,609	(a)
Rock-Tenn Co., Senior Notes	4.900	%	3/1/22	790,000	820,635	(a)
*Total Containers & Packaging*					*1,650,244*
*Metals & Mining — 4.2%*
Barrick Gold Corp., Senior Notes	5.250	%	4/1/42	1,380,000	1,457,714	(a)
Cliffs Natural Resources Inc., Senior Notes	4.875	%	4/1/21	620,000	646,602
Freeport-McMoRan Copper & Gold Inc., Senior Notes	3.550	%	3/1/22	705,000	700,655
Rio Tinto Finance USA Ltd., Senior Notes	9.000	%	5/1/19	2,000,000	2,751,632
Southern Copper Corp., Senior Notes	5.375	%	4/16/20	260,000	286,872
Vale Overseas Ltd., Notes	6.875	%	11/21/36	2,100,000	2,413,473
Xstrata Finance Canada Ltd., Senior Bonds	5.800	%	11/15/16	1,200,000	1,355,063	(a)
*Total Metals & Mining*					*9,612,011*
*Paper & Forest Products — 0.6%*
NewPage Corp., Senior Secured Notes	11.375	%	12/31/14	500,000	312,500	(e)
PE Paper Escrow GmbH, Senior Secured Notes	12.000	%	8/1/14	1,030,000	1,107,250	(a)
*Total Paper & Forest Products*					*1,419,750*
Total Materials					14,154,284

See Notes to Financial Statements.

Western Asset Investment Grade Defined Opportunity Trust Inc. 2012 Semi-Annual Report

Western Asset Investment Grade Defined Opportunity Trust Inc.

Security	Rate		Maturity Date	Face Amount	Value
Telecommunication Services — 7.2%
*Diversified Telecommunication Services — 4.5%*
AT&T Inc., Global Notes	5.600	%	5/15/18	$1,500,000	$ 1,792,395
AT&T Inc., Global Notes	6.550	%	2/15/39	250,000	320,271
AT&T Inc., Senior Notes	5.550	%	8/15/41	1,060,000	1,247,123
British Telecommunications PLC, Bonds	9.875	%	12/15/30	2,000,000	3,031,078
Embarq Corp., Notes	7.995	%	6/1/36	1,500,000	1,541,068
Koninklijke KPN NV, Senior Notes	8.375	%	10/1/30	330,000	443,651
Telecom Italia Capital SA, Senior Notes	7.721	%	6/4/38	1,000,000	885,000
Telefonica Emisiones SAU, Senior Notes	5.877	%	7/15/19	400,000	373,968
Verizon Communications Inc., Senior Notes	8.950	%	3/1/39	430,000	697,875
*Total Diversified Telecommunication Services*					*10,332,429*
*Wireless Telecommunication Services — 2.7%*
America Movil SAB de CV, Senior Notes	6.125	%	3/30/40	1,400,000	1,680,781
Cellco Partnership/Verizon Wireless Capital LLC, Senior Notes	8.500	%	11/15/18	2,000,000	2,739,448
Rogers Communications Inc., Senior Notes	6.800	%	8/15/18	1,000,000	1,234,627
Sprint Nextel Corp., Senior Notes	9.000	%	11/15/18	280,000	303,800	(a)
Telefonica Europe BV	8.250	%	9/15/30	390,000	382,295
*Total Wireless Telecommunication Services*					*6,340,951*
Total Telecommunication Services					16,673,380
Utilities — 7.2%
*Electric Utilities — 5.5%*
Commonwealth Edison Co., First Mortgage Bonds	5.800	%	3/15/18	600,000	727,634
Commonwealth Edison Co., First Mortgage Bonds	6.450	%	1/15/38	600,000	841,238
FirstEnergy Corp., Notes	7.375	%	11/15/31	2,230,000	2,847,139
IPALCO Enterprises Inc., Senior Secured Notes	7.250	%	4/1/16	1,030,000	1,122,700	(a)
MidAmerican Energy Holdings Co., Bonds	6.125	%	4/1/36	1,000,000	1,271,705
MidAmerican Energy Holdings Co., Senior Notes	5.750	%	4/1/18	1,000,000	1,190,260
Pacific Gas & Electric Co., Senior Notes	8.250	%	10/15/18	600,000	812,443
Pacific Gas & Electric Co., Senior Notes	5.800	%	3/1/37	820,000	1,029,129
Reliant Energy Mid-Atlantic Power Holdings LLC, Senior Notes	9.681	%	7/2/26	2,000,000	1,900,000
Virginia Electric and Power Co., Senior Notes	8.875	%	11/15/38	500,000	848,555
*Total Electric Utilities*					*12,590,803*
*Gas Utilities — 0.9%*
Southern Natural Gas Co., Senior Notes	8.000	%	3/1/32	1,500,000	*2,029,282*
*Independent Power Producers & Energy Traders — 0.5%*
AES Corp., Senior Notes	8.000	%	6/1/20	1,100,000	*1,243,000*

See Notes to Financial Statements.

Western Asset Investment Grade Defined Opportunity Trust Inc. 2012 Semi-Annual Report

Schedule of investments (unaudited) (cont’d)

May 31, 2012

Western Asset Investment Grade Defined Opportunity Trust Inc.

Security		Rate		Maturity Date	Face Amount	Value
*Multi-Utilities — 0.3%*
Dominion Resources Inc., Senior Notes		8.875	%	1/15/19	$ 500,000	$ 689,975
Total Utilities						16,553,060
Total Corporate Bonds & Notes (Cost — $188,682,306)						213,301,706
Collateralized Senior Loans — 2.3%
Consumer Discretionary — 0.6%
*Hotels, Restaurants & Leisure — 0.4%*
CCM Merger Inc., New Term Loan B		6.000	%	3/1/17	897,131	*892,645*	(f)
*Media — 0.2%*
Cengage Learning Acquisitions Inc., Extended Term Loan		5.740	%	7/5/17	680,407	*578,346*	(f)
Total Consumer Discretionary						1,470,991
Energy — 0.2%
*Oil, Gas & Consumable Fuels — 0.2%*
Chesapeake Energy Corp., Term Loan		—		12/1/17	430,000	420,003	(g)
Health Care — 0.4%
*Health Care Equipment & Supplies — 0.4%*
Fenwal Inc., First Lien Term Loan	2.489 - 2.717		%	2/28/14	933,082	909,755	(f)
Industrials — 0.4%
*Commercial Services & Supplies — 0.4%*
Nielsen Finance LLC, Term Loan B		3.989	%	5/2/16	970,219	965,489	(f)
Information Technology — 0.4%
*IT Services — 0.4%*
First Data Corp., Extended Term Loan B		4.239	%	3/23/18	401,246	365,594	(f)
First Data Corp., Non-Extended Term Loan B2		2.989	%	9/24/14	486,648	462,924	(f)
Total Information Technology						828,518
Utilities — 0.3%
*Electric Utilities — 0.3%*
Texas Competitive Electric Holdings Co. LLC, Extended Term Loan		4.739	%	10/10/17	944,308	552,774	(f)
Total Collateralized Senior Loans (Cost — $5,220,014)						5,147,530
Municipal Bonds — 0.5%
*Illinois — 0.5%*
Illinois State, GO		5.665	%	3/1/18	530,000	590,033
Illinois State, GO		5.877	%	3/1/19	530,000	592,530
Total Municipal Bonds (Cost — $1,060,000)						1,182,563

See Notes to Financial Statements.

Western Asset Investment Grade Defined Opportunity Trust Inc. 2012 Semi-Annual Report

Western Asset Investment Grade Defined Opportunity Trust Inc.

Security	Rate		Maturity Date	Face Amount	Value
Sovereign Bonds — 0.9%
*Russia — 0.9%*
RSHB Capital, Loan Participation Notes, Senior Secured Notes	9.000	%	6/11/14	$1,000,000	$ 1,101,450	(a)
Russian Foreign Bond — Eurobond, Senior Bonds	7.500	%	3/31/30	805,000	948,894	(a)
Total Sovereign Bonds (Cost — $1,823,278)					2,050,344

				Shares
Convertible Preferred Stocks — 0.3%
Financials — 0.3%
Citigroup Inc. (Cost — $888,750)	7.500	%		7,500	630,600
Preferred Stocks — 2.2%
Financials — 2.2%
*Commercial Banks — 0.7%*
PNC Financial Services Group Inc.	6.125	%		16,650	427,905	(b)
Santander Finance Preferred SA Unipersonal	10.500	%		7,725	194,284
U.S. Bancorp	6.000	%		39,550	1,024,345	(b)
*Total Commercial Banks*					*1,646,534*
*Consumer Finance — 1.0%*
GMAC Capital Trust I	8.125	%		98,600	*2,259,912*	(b)
*Diversified Financial Services — 0.5%*
Citigroup Capital XIII	7.875	%		45,600	*1,206,576*	(b)
Total Preferred Stocks (Cost — $5,190,744)					5,113,022
Total Investments before Short-Term Investments (Cost — $202,865,092)					227,425,765

				Face Amount
Short-Term Investments — 0.4%
*Repurchase Agreements — 0.4%*
Goldman Sachs & Co. repurchase agreement dated 5/31/12; Proceeds at maturity — $1,000,005; (Fully collateralized by U.S. government agency obligations, 0.200% due 2/27/13; Market value — $1,025,000) (Cost — $1,000,000)	0.170	%	6/1/12	$1,000,000	1,000,000
Total Investments — 99.2% (Cost — $203,865,092#)					228,425,765
Other Assets in Excess of Liabilities — 0.8%					1,859,032
Total Net Assets — 100.0%					$230,284,797

See Notes to Financial Statements.

Western Asset Investment Grade Defined Opportunity Trust Inc. 2012 Semi-Annual Report

Schedule of investments (unaudited) (cont’d)

May 31, 2012

Western Asset Investment Grade Defined Opportunity Trust Inc.

(a)	Security is exempt from registration under Rule 144A of the Securities Act of 1933. This security may be resold in transactions that are exempt from registration, normally to qualified institutional buyers. This security has been deemed liquid pursuant to guidelines approved by the Board of Directors, unless otherwise noted.
(b)	Variable rate security. Interest rate disclosed is as of the most recent information available.
(c)	Security has no maturity date. The date shown represents the next call date.
(d)	Payment-in-kind security for which part of the income earned may be paid as additional principal.
(e)	The coupon payment on these securities is currently in default as of May 31, 2012.
(f)	Interest rates disclosed represent the effective rates on collateralized senior loans. Ranges in interest rates are attributable to multiple contracts under the same loan.
(g)	All or a portion of this loan is unfunded as of May 31, 2012. The interest rate for fully unfunded term loans is to be determined.
#	Aggregate cost for federal income tax purposes is substantially the same.

	Abbreviation used in this schedule:
	GO	— General Obligation

See Notes to Financial Statements.

Western Asset Investment Grade Defined Opportunity Trust Inc. 2012 Semi-Annual Report

Statement of assets and liabilities (unaudited)

May 31, 2012

Assets:
Investments, at value (Cost — $203,865,092)		$228,425,765
Cash		484,504
Interest receivable		3,481,761
Receivable for securities sold		2,090,559
Deposits with brokers for open futures contracts		521,003
Unrealized appreciation on forward foreign currency contracts		99,253
Prepaid expenses		22,858
*Total Assets*		*235,125,703*

Liabilities:
Payable for securities purchased		4,552,632
Investment management fee payable		127,161
Payable to broker — variation margin on open futures contracts		103,771
Accrued expenses		57,342
*Total Liabilities*		*4,840,906*
Total Net Assets		$230,284,797

Net Assets:
Par value ($0.001 par value; 10,716,079 shares issued and outstanding; 100,000,000 shares authorized)		$ 10,716
Paid-in capital in excess of par value		204,371,368
Undistributed net investment income		1,720,189
Accumulated net realized loss on investments, futures contracts, swap contracts and foreign currency transactions		(40,580)
Net unrealized appreciation on investments, futures contracts and foreign currencies		24,223,104
Total Net Assets		$230,284,797

Shares Outstanding		10,716,079

Net Asset Value		$21.49

See Notes to Financial Statements.

Western Asset Investment Grade Defined Opportunity Trust Inc. 2012 Semi-Annual Report

Statement of operations (unaudited)

For the Six Months Ended May 31, 2012

Investment Income:
Interest		$ 6,749,660
Dividends		177,731
*Total Investment Income*		*6,927,391*

Expenses:
Investment management fee (Note 2)		743,063
Excise tax (Note 1)		49,223
Audit and tax		28,172
Directors’ fees		19,596
Transfer agent fees		17,153
Shareholder reports		14,864
Fund accounting fees		11,321
Legal fees		10,673
Stock exchange listing fees		8,524
Insurance		2,901
Custody fees		1,953
Miscellaneous expenses		3,015
*Total Expenses*		*910,458*
Net Investment Income		6,016,933

Realized and Unrealized Gain (Loss) on Investments, Futures Contracts, Swap Contracts and Foreign Currency Transactions (Notes 1, 3 and 4):
Net Realized Gain (Loss) From:
Investment transactions		2,038,849
Futures contracts		(1,161,263)
Swap contracts		27,427
Foreign currency transactions		130,141
*Net Realized Gain*		*1,035,154*
Change in Net Unrealized Appreciation (Depreciation) From:
Investments		10,832,389
Futures contracts		(617,374)
Foreign currencies		47,277
*Change in Net Unrealized Appreciation (Depreciation)*		*10,262,292*
Net Gain on Investments, Futures Contracts, Swap Contracts and Foreign Currency Transactions		11,297,446
Increase in Net Assets From Operations		$17,314,379

See Notes to Financial Statements.

Western Asset Investment Grade Defined Opportunity Trust Inc. 2012 Semi-Annual Report

Statements of changes in net assets

For the Six Months Ended May 31, 2012 (unaudited) and the Year Ended November 30, 2011	2012	2011

Operations:
Net investment income	$ 6,016,933	$ 12,279,329
Net realized gain	1,035,154	1,492,940
Change in net unrealized appreciation (depreciation)	10,262,292	(7,611,127)
*Increase in Net Assets From Operations*	*17,314,379*	*6,161,142*

Distributions to Shareholders From (Note 1):
Net investment income	(6,706,808)	(11,428,059)
Net realized gains	(1,512,836)	(2,329,225)
*Decrease in Net Assets From Distributions to Shareholders*	*(8,219,644)*	*(13,757,284)*

Fund Share Transactions:
Reinvestment of distributions (39,751 and 29,395 shares issued, respectively)	836,029	612,686
*Increase in Net Assets From Fund Share Transactions*	*836,029*	*612,686*
*Increase (Decrease) in Net Assets*	*9,930,764*	*(6,983,456)*

Net Assets:
Beginning of period	220,354,033	227,337,489
End of period*	$230,284,797	$220,354,033
*Includes undistributed net investment income of:	$1,720,189	$2,410,064

See Notes to Financial Statements.

Western Asset Investment Grade Defined Opportunity Trust Inc. 2012 Semi-Annual Report

Financial highlights

For a share of capital stock outstanding throughout each year ended November 30, unless otherwise noted:

	20121,2		20112		20102		20092,3

Net asset value, beginning of period	$20.64		$21.35		$20.58		$19.064

Income (loss) from operations:
Net investment income	0.56		1.15		1.17		0.44
Net realized and unrealized gain (loss)	1.06		(0.57)		0.85		1.50
*Total income from operations*	*1.62*		*0.58*		*2.02*		*1.94*

Less distributions from:
Net investment income	(0.63)		(1.07)		(1.17)		(0.42)
Net realized gains	(0.14)		(0.22)		(0.08)		—
*Total distributions*	*(0.77)*		*(1.29)*		*(1.25)*		*(0.42)*

Net asset value, end of period	$21.49		$20.64		$21.35		$20.58

Market price, end of period	$22.87		$21.55		$20.79		$19.64
*Total return, based on NAV5,6***	*7.95*	%	*2.96*	%	*10.28*	%	*10.32*	%
*Total return, based on market price*7	*10.06*	%	*10.40*	%	*12.52*	%	*0.33*	%

Net assets, end of period (000s)	$230,285		$220,354		$227,337		$216,952

Ratios to average net assets:
Gross expenses	0.80	%8	0.80	%	0.81	%	0.86	%8
Net expenses9	0.80	8	0.80		0.81		0.83	8,10
Net investment income	5.26	8	5.43		5.60		5.12	8

Portfolio turnover rate	39	%	49	%	31	%	19	%

1	For the six months ended May 31, 2012 (unaudited).
2	Per share amounts have been calculated using the average shares method.
3	For the period June 26, 2009 (commencement of operations) through November 30, 2009.
4	Initial public offering price of $20.00 per share less offering costs and sales load totaling $0.94 per share.
5	Performance figures may reflect compensating balance arrangements, fee waivers and/or expense reimbursements. In the absence of compensating balance arrangements, fee waivers and/or expense reimbursements, the total return would have been lower. Past performance is no guarantee of future results. Total returns for periods of less than one year are not annualized.
6	The total return calculation assumes that distributions are reinvested at NAV. Prior to Janaury 1, 2012, the total return calculation assumed the reinvestment of all distributions in accordance with the Fund’s dividend reinvestment plan. Past performance is no guarantee of future results. Total returns for periods of less than one year are not annualized.
7	The total return calculation assumes that distributions are reinvested in accordance with the Fund’s dividend reinvestment plan. Past performance is no guarantee of future results. Total returns for periods of less than one year are not annualized.
8	Annualized.
9	The impact of compensating balance arrangements, if any, was less than 0.01%.
10	The investment manager has agreed to reimburse all organization expenses.

See Notes to Financial Statements.

Western Asset Investment Grade Defined Opportunity Trust Inc. 2012 Semi-Annual Report

Notes to financial statements (unaudited)

1. Organization and significant accounting policies

Western Asset Investment Grade Defined Opportunity Trust Inc. (the “Fund”) was incorporated in Maryland on April 24, 2009 and is registered as a non-diversified, closed-end management investment company under the Investment Company Act of 1940, as amended (the “1940 Act”). The Fund’s primary investment objective is to provide current income and then to liquidate and distribute substantially all of the Fund’s net assets to stockholders on or about December 2, 2024. As a secondary investment objective, the Fund will seek capital appreciation. There can be no assurance the Fund will achieve its investment objectives.

The following are significant accounting policies consistently followed by the Fund and are in conformity with U.S. generally accepted accounting principles (“GAAP”). Estimates and assumptions are required to be made regarding assets, liabilities and changes in net assets resulting from operations when financial statements are prepared. Changes in the economic environment, financial markets and any other parameters used in determining these estimates could cause actual results to differ. Subsequent events have been evaluated through the date the financial statements were issued.

(a) Investment valuation. The valuations for fixed income securities (which may include, but are not limited to, corporate, government, municipal, mortgage-backed, collateralized mortgage obligations and asset-backed securities) and certain derivative instruments are typically the prices supplied by independent third party pricing services, which may use market prices or broker/dealer quotations or a variety of valuation techniques and methodologies. The independent third party pricing services’ internal models use inputs that are observable such as issuer details, interest rates, yield curves, prepayment speeds, credit risks/spreads, default rates and quoted prices for similar securities. Short-term fixed income securities that will mature in 60 days or less are valued at amortized cost, unless it is determined that using this method would not reflect an investment’s fair value. Futures contracts are valued daily at the settlement price established by the board of trade or exchange on which they are traded. Equity securities for which market quotations are available are valued at the last reported sales price or official closing price on the primary market or exchange on which they trade. When the Fund holds securities or other assets that are denominated in a foreign currency, the Fund will normally use the currency exchange rates as of 4:00 p.m. (Eastern Time). If independent third party pricing services are unable to supply prices for a portfolio investment, or if the prices supplied are deemed by the manager to be unreliable, the market price may be determined by the manager using quotations from one or more broker/dealers or at the transaction price if the security has recently been purchased and no value has yet been obtained from a pricing service or pricing broker. When reliable prices are not readily available, such as when the value of a security has been significantly

Western Asset Investment Grade Defined Opportunity Trust Inc. 2012 Semi-Annual Report

Notes to financial statements (unaudited) (cont’d)

affected by events after the close of the exchange or market on which the security is principally traded, but before the Fund calculates its net asset value, the Fund values these securities as determined in accordance with procedures approved by the Fund’s Board of Directors.

The Board of Directors is responsible for the valuation process and has delegated the supervision of the daily valuation process to the Legg Mason North American Fund Valuation Committee (the “Valuation Committee”). The Valuation Committee, pursuant to the policies adopted by the Board of Directors, is responsible for making fair value determinations, evaluating the effectiveness of the Fund’s pricing policies, and reporting to the Board of Directors. When determining the reliability of third party pricing information for investments owned by the Fund, the Valuation Committee, among other things, conducts due diligence reviews of pricing vendors, monitors the daily change in prices and reviews transactions among market participants.

The Valuation Committee will consider pricing methodologies it deems relevant and appropriate when making fair value determinations. Examples of possible methodologies include, but are not limited to, multiple of earnings; discount from market of a similar freely traded security; discounted cash-flow analysis; book value or a multiple thereof; risk premium/yield analysis; yield to maturity; and/or fundamental investment analysis. The Valuation Committee will also consider factors it deems relevant and appropriate in light of the facts and circumstances. Examples of possible factors include, but are not limited to, the type of security; the issuer’s financial statements; the purchase price of the security; the discount from market value of unrestricted securities of the same class at the time of purchase; analysts’ research and observations from financial institutions; information regarding any transactions or offers with respect to the security; the existence of merger proposals or tender offers affecting the security; the price and extent of public trading in similar securities of the issuer or comparable companies; and the existence of a shelf registration for restricted securities.

For each portfolio security that has been fair valued pursuant to the policies adopted by the Board of Directors, the fair value price is compared against the last available and next available market quotations. The Valuation Committee reviews the results of such back testing monthly and fair valuation occurrences are reported to the Board of Directors quarterly.

The Fund uses valuation techniques to measure fair value that are consistent with the market approach and/or income approach, depending on the type of security and the particular circumstance. The market approach uses prices and other relevant information generated by market transactions involving identical or comparable securities. The income approach uses valuation techniques to discount estimated future cash flows to present value.

Western Asset Investment Grade Defined Opportunity Trust Inc. 2012 Semi-Annual Report

GAAP establishes a disclosure hierarchy that categorizes the inputs to valuation techniques used to value assets and liabilities at measurement date. These inputs are summarized in the three broad levels listed below:

· Level 1 — quoted prices in active markets for identical investments

· Level 2 — other significant observable inputs (including quoted prices for similar investments, interest rates, prepayment speeds, credit risk, etc.)

· Level 3 — significant unobservable inputs (including the Fund’s own assumptions in determining the fair value of investments)

The inputs or methodologies used to value securities are not necessarily an indication of the risk associated with investing in those securities.

The following is a summary of the inputs used in valuing the Fund’s assets and liabilities carried at fair value:

ASSETS
Description	Quoted Prices (Level 1)	Other Significant Observable Inputs (Level 2)	Significant Unobservable Inputs (Level 3)	Total
Long-term investments†:
Corporate bonds & notes	—	$213,301,706	—	$213,301,706
Collateralized senior loans	—	5,147,530	—	5,147,530
Municipal bonds	—	1,182,563	—	1,182,563
Sovereign bonds	—	2,050,344	—	2,050,344
Convertible preferred stocks	$ 630,600	—	—	630,600
Preferred stocks	5,113,022	—	—	5,113,022
Total long-term investments	$5,743,622	$221,682,143	—	$227,425,765
Short-term investments†	—	1,000,000	—	1,000,000
Total investments	$5,743,622	$222,682,143	—	$228,425,765
Other financial instruments:
Futures contracts	$ 53,978	—	—	$ 53,978
Forward foreign currency contracts	—	$ 99,253	—	99,253
Total other financial instruments	$ 53,978	$ 99,253	—	$ 153,231
Total	$5,797,600	$ 222,781,396	—	$228,578,996

LIABILITIES
Description	Quoted Prices (Level 1)	Other Significant Observable Inputs (Level 2)	Significant Unobservable Inputs (Level 3)	Total
Other financial instruments:
Futures contracts	$490,800	—	—	$490,800

† See Schedule of Investments for additional detailed categorizations.

(b) Repurchase agreements. The Fund may enter into repurchase agreements with institutions that its investment adviser has determined are creditworthy. Each repurchase agreement is recorded at cost. Under the terms of a typical repurchase agreement, the Fund acquires a debt security subject to an obligation of the seller to repurchase, and of the Fund to resell, the security at an

Western Asset Investment Grade Defined Opportunity Trust Inc. 2012 Semi-Annual Report

Notes to financial statements (unaudited) (cont’d)

agreed-upon price and time, thereby determining the yield during the Fund’s holding period. When entering into repurchase agreements, it is the Fund’s policy that its custodian or a third party custodian, acting on the Fund’s behalf, take possession of the underlying collateral securities, the market value of which, at all times, at least equals the principal amount of the repurchase transaction, including accrued interest. To the extent that any repurchase transaction maturity exceeds one business day, the value of the collateral is marked-to-market and measured against the value of the agreement in an effort to ensure the adequacy of the collateral. If the counterparty defaults, the Fund generally has the right to use the collateral to satisfy the terms of the repurchase transaction. However, if the market value of the collateral declines during the period in which the Fund seeks to assert its rights or if bankruptcy proceedings are commenced with respect to the seller of the security, realization of the collateral by the Fund may be delayed or limited.

(c) Futures contracts. The Fund uses futures contracts generally to gain exposure to, or hedge against, changes in interest rates or gain exposure to, or hedge against, changes in certain asset classes. A futures contract represents a commitment for the future purchase or sale of an asset at a specified price on a specified date.

Upon entering into a futures contract, the Fund is required to deposit cash or cash equivalents with a broker in an amount equal to a certain percentage of the contract amount. This is known as the ‘‘initial margin’’ and subsequent payments (‘‘variation margin’’) are made or received by the Fund each day, depending on the daily fluctuation in the value of the contract. For certain futures, including foreign denominated futures, variation margin is not settled daily, but is recorded as a net variation margin payable or receivable. Futures contracts are valued daily at the settlement price established by the board of trade or exchange on which they are traded. The daily changes in contract value are recorded as unrealized gains or losses in the Statement of Operations and the Fund recognizes a realized gain or loss when the contract is closed.

Futures contracts involve, to varying degrees, risk of loss in excess of the amounts reflected in the financial statements. In addition, there is the risk that the Fund may not be able to enter into a closing transaction because of an illiquid secondary market.

(d) Forward foreign currency contracts. The Fund enters into forward foreign currency contracts to hedge against, or manage exposure to, foreign issuers or markets. The Fund may also enter into a forward foreign currency contract to hedge against foreign currency exchange rate risk on its non-U.S. dollar denominated securities or to facilitate settlement of a foreign currency denominated portfolio transaction. A forward foreign currency contract is an agreement between two parties to buy and sell a currency at a set price with delivery and settlement at a future date. The contract is marked-to-market

Western Asset Investment Grade Defined Opportunity Trust Inc. 2012 Semi-Annual Report

daily and the change in value is recorded by the Fund as an unrealized gain or loss. When a forward foreign currency contract is closed, through either delivery or offset by entering into another forward foreign currency contract, the Fund recognizes a realized gain or loss equal to the difference between the value of the contract at the time it was opened and the value of the contract at the time it is closed.

Forward foreign currency contracts involve elements of market risk in excess of the amounts reflected on the Statement of Assets and Liabilities. The Fund bears the risk of an unfavorable change in the foreign exchange rate underlying the forward foreign currency contract. Risks may also arise upon entering into these contracts from the potential inability of the counterparties to meet the terms of their contracts.

(e) Swap agreements. The Fund invests in swaps for the purpose of managing its exposure to interest rate, credit or market risk, or for other purposes, including to increase the Fund’s return. The use of swaps involves risks that are different from those associated with other portfolio transactions.

Swap contracts are marked-to-market daily and changes in value are recorded as unrealized appreciation (depreciation). Gains or losses are realized upon termination of the swap agreement. Collateral, in the form of restricted cash or securities, may be required to be held in segregated accounts with the Fund’s custodian in compliance with the terms of the swap contracts. Securities posted as collateral for swap contracts are identified in the Schedule of Investments and restricted cash, if any, is identified on the Statement of Assets and Liabilities. Risks may exceed amounts recorded in the Statement of Assets and Liabilities. These risks include changes in the returns of the underlying instruments, failure of the counterparties to perform under the contracts’ terms, and the possible lack of liquidity with respect to the swap agreements.

Payments received or made at the beginning of the measurement period are reflected as a premium or deposit, respectively, on the Statement of Assets and Liabilities. These upfront payments are amortized over the life of the swap and are recognized as realized gain or loss in the Statement of Operations. Net periodic payments received or paid by the Fund are recognized as a realized gain or loss in the Statement of Operations.

The Fund’s maximum exposure in the event of a defined credit event on a credit default swap to sell protection is the notional amount. As of May 31, 2012, the Fund did not hold any credit default swaps to sell protection.

For average notional amounts of swaps held during the six months ended May 31, 2012, see Note 4.

Credit default swaps

The Fund enters into credit default swap (“CDS”) contracts for investment purposes, to manage its credit risk or to add leverage. CDS agreements

Western Asset Investment Grade Defined Opportunity Trust Inc. 2012 Semi-Annual Report

Notes to financial statements (unaudited) (cont’d)

involve one party making a stream of payments to another party in exchange for the right to receive a specified return in the event of a default by a third party, typically corporate or sovereign issuers, on a specified obligation, or in the event of a write-down, principal shortfall, interest shortfall or default of all or part of the referenced entities comprising a credit index. The Fund may use a CDS to provide protection against defaults of the issuers (i.e., to reduce risk where the Fund has exposure to an issuer) or to take an active long or short position with respect to the likelihood of a particular issuer’s default. As a seller of protection, the Fund generally receives an upfront payment or a stream of payments throughout the term of the swap provided that there is no credit event. If the Fund is a seller of protection and a credit event occurs, as defined under the terms of that particular swap agreement, the maximum potential amount of future payments (undiscounted) that the Fund could be required to make under a credit default swap agreement would be an amount equal to the notional amount of the agreement. These amounts of potential payments will be partially offset by any recovery of values from the respective referenced obligations. As a seller of protection, the Fund effectively adds leverage to its portfolio because, in addition to its total net assets, the Fund is subject to investment exposure on the notional amount of the swap. As a buyer of protection, the Fund generally receives an amount up to the notional value of the swap if a credit event occurs.

Implied spreads are the theoretical prices a lender receives for credit default protection. When spreads rise, market perceived credit risk rises and when spreads fall, market perceived credit risk falls. The implied credit spread of a particular referenced entity reflects the cost of buying/selling protection and may include upfront payments required to enter into the agreement. Wider credit spreads and decreasing market values, when compared to the notional amount of the swap, represent a deterioration of the referenced entity’s credit soundness and a greater likelihood or risk of default or other credit event occurring as defined under the terms of the agreement. Credit spreads utilized in determining the period end market value of credit default swap agreements on corporate or sovereign issues are disclosed in the Notes to Financial Statements and serve as an indicator of the current status of the payment/performance risk and represent the likelihood or risk of default for credit derivatives. For credit default swap agreements on asset-backed securities and credit indices, the quoted market prices and resulting values, particularly in relation to the notional amount of the contract as well as the annual payment rate, serve as an indication of the current status of the payment/performance risk.

The Fund’s maximum risk of loss from counterparty risk, as the protection buyer, is the fair value of the contract (this risk is mitigated by the posting of collateral by the counterparty to the Fund to cover the Fund’s exposure to the counterparty). As the protection seller, the Fund’s maximum risk is the notional amount of the contract. Credit default swaps are considered to have credit

Western Asset Investment Grade Defined Opportunity Trust Inc. 2012 Semi-Annual Report

risk-related contingent features since they require payment by the protection seller to the protection buyer upon the occurrence of a defined credit event.

Entering into a CDS agreement involves, to varying degrees, elements of credit, market and documentation risk in excess of the related amounts recognized on the Statement of Assets and Liabilities. Such risks involve the possibility that there will be no liquid market for these agreements, that the counterparty to the agreement may default on its obligation to perform or disagree as to the meaning of the contractual terms in the agreement, and that there will be unfavorable changes in net interest rates.

(f) Loan participations. The Fund may invest in loans arranged through private negotiation between one or more financial institutions. The Fund’s investment in any such loan may be in the form of a participation in or an assignment of the loan. In connection with purchasing participations, the Fund generally will have no right to enforce compliance by the borrower with the terms of the loan agreement related to the loan, or any rights of off-set against the borrower and the Fund may not benefit directly from any collateral supporting the loan in which it has purchased the participation.

The Fund assumes the credit risk of the borrower, the lender that is selling the participation and any other persons interpositioned between the Fund and the borrower. In the event of the insolvency of the lender selling the participation, the Fund may be treated as a general creditor of the lender and may not benefit from any off-set between the lender and the borrower.

(g) Unfunded loan commitments. The Fund may enter into certain credit agreements all or a portion of which may be unfunded. The Fund is obligated to fund these commitments at the borrower’s discretion. The commitments are disclosed in the accompanying Schedule of Investments. At May 31, 2012, the Fund had sufficient cash and/or securities to cover these commitments.

(h) Credit and market risk. The Fund invests in high-yield instruments that are subject to certain credit and market risks. The yields of high-yield obligations reflect, among other things, perceived credit and market risks. The Fund’s investment in securities rated below investment grade typically involves risks not associated with higher rated securities including, among others, greater risk related to timely and ultimate payment of interest and principal, greater market price volatility and less liquid secondary market trading.

(i) Foreign investment risks. The Fund’s investments in foreign securities may involve risks not present in domestic investments. Since securities may be denominated in foreign currencies, may require settlement in foreign currencies or pay interest or dividends in foreign currencies, changes in the relationship of these foreign currencies to the U.S. dollar can significantly affect the value of the investments and earnings of the Fund. Foreign investments may also subject the Fund to foreign government exchange restrictions,

Western Asset Investment Grade Defined Opportunity Trust Inc. 2012 Semi-Annual Report

Notes to financial statements (unaudited) (cont’d)

expropriation, taxation or other political, social or economic developments, all of which affect the market and/or credit risk of the investments.

(j) Counterparty risk and credit-risk-related contingent features of derivative instruments. The Fund may invest in certain securities or engage in other transactions, where the Fund is exposed to counterparty credit risk in addition to broader market risks. The Fund may invest in securities of issuers, which may also be considered counterparties as trading partners in other transactions. This may increase the risk of loss in the event of default or bankruptcy by the counterparty or if the counterparty otherwise fails to meet its contractual obligations. The Fund’s investment manager attempts to mitigate counterparty risk by (i) periodically assessing the creditworthiness of its trading partners, (ii) monitoring and/or limiting the amount of its net exposure to each individual counterparty based on its assessment and (iii) requiring collateral from the counterparty for certain transactions. Market events and changes in overall economic conditions may impact the assessment of such counterparty risk by the investment manager. In addition, declines in the values of underlying collateral received may expose the Fund to increased risk of loss.

The Fund has entered into master agreements with certain of its derivative counterparties that provide for general obligations, representations, agreements, collateral, events of default or termination and credit related contingent features. The credit related contingent features include, but are not limited to, a percentage decrease in the Fund’s net assets or NAV over a specified period of time. If these credit related contingent features were triggered, the derivatives counterparty could terminate the positions and demand payment or require additional collateral.

As of May 31, 2012, the Fund did not have any open derivative transactions with credit related contingent features in a net liability position.

(k) Foreign currency translation. Investment securities and other assets and liabilities denominated in foreign currencies are translated into U.S. dollar amounts based upon prevailing exchange rates on the date of valuation. Purchases and sales of investment securities and income and expense items denominated in foreign currencies are translated into U.S. dollar amounts based upon prevailing exchange rates on the respective dates of such transactions.

The Fund does not isolate that portion of the results of operations resulting from fluctuations in foreign exchange rates on investments from the fluctuations arising from changes in market prices of securities held. Such fluctuations are included with the net realized and unrealized gain or loss on investments.

Net realized foreign exchange gains or losses arise from sales of foreign currencies, including gains and losses on forward foreign currency contracts, currency gains or losses realized between the trade and settlement dates on

Western Asset Investment Grade Defined Opportunity Trust Inc. 2012 Semi-Annual Report

securities transactions, and the difference between the amounts of dividends, interest, and foreign withholding taxes recorded on the Fund’s books and the U.S. dollar equivalent of the amounts actually received or paid. Net unrealized foreign exchange gains and losses arise from changes in the values of assets and liabilities, other than investments in securities, on the date of valuation, resulting from changes in exchange rates.

Foreign security and currency transactions may involve certain considerations and risks not typically associated with those of U.S. dollar denominated transactions as a result of, among other factors, the possibility of lower levels of governmental supervision and regulation of foreign securities markets and the possibility of political or economic instability.

(l) Security transactions and investment income. Security transactions are accounted for on a trade date basis. Interest income, adjusted for amortization of premium and accretion of discount, is recorded on the accrual basis. Dividend income is recorded on the ex-dividend date. Foreign dividend income is recorded on the ex-dividend date or as soon as practicable after the Fund determines the existance of a dividend declaration after exercising reasonable due diligence. The cost of investments sold is determined by use of the specific identification method. To the extent any issuer defaults or a credit event occurs that impacts the issuer, the Fund may halt any additional interest income accruals and consider the realizability of interest accrued up to the date of default or credit event.

(m) Distributions to shareholders. Distributions from net investment income of the Fund, if any, are declared quarterly and paid on a monthly basis. Distributions of net realized gains, if any, are declared at least annually. Distributions to shareholders of the Fund are recorded on the ex-dividend date and are determined in accordance with income tax regulations, which may differ from GAAP.

(n) Compensating balance arrangements. The Fund has an arrangement with its custodian bank whereby a portion of the custodian’s fees is paid indirectly by credits earned on the Fund’s cash on deposit with the bank.

(o) Federal and other taxes. It is the Fund’s policy to comply with the federal income and excise tax requirements of the Internal Revenue Code of 1986 (the “Code”), as amended, applicable to regulated investment companies. Accordingly, the Fund intends to distribute its taxable income and net realized gains, if any, to shareholders in accordance with timing requirements imposed by the Code. Therefore, no federal or state income tax provision is required in the Fund’s financial statements. However, due to the timing of when distributions are made, the Fund may be subject to an excise tax of 4% of the amount by which 98% of the Fund’s annual taxable income and 98.2% of net realized gains exceed the distributions from such taxable income and realized gains for the calendar year. The Fund paid $86,055 of federal excise tax attributable to calendar year 2011 in March 2012.

Western Asset Investment Grade Defined Opportunity Trust Inc. 2012 Semi-Annual Report

Notes to financial statements (unaudited) (cont’d)

Management has analyzed the Fund’s tax positions taken on income tax returns for all open tax years and has concluded that as of May 31, 2012 no provision for income tax is required in the Fund’s financial statements. The Fund’s federal and state income and federal excise tax returns for tax years for which the applicable statutes of limitations have not expired are subject to examination by Internal Revenue Service and state departments of revenue.

(p) Reclassification. GAAP requires that certain components of net assets be reclassified to reflect permanent differences between financial and tax reporting. These reclassifications have no effect on net assets or net asset value per share.

2. Investment management agreement and other transactions with affiliates

Legg Mason Partners Fund Advisor, LLC (“LMPFA”) is the Fund’s investment manager. Western Asset Management Company (“Western Asset”), Western Asset Management Company Pte. Ltd. (“Western Singapore”), Western Asset Management Company Ltd (“Western Japan”) and Western Asset Management Company Limited (“Western Asset Limited”) are the Fund’s subadvisers. LMPFA, Western Asset, Western Singapore, Western Japan and Western Asset Limited are wholly-owned subsidiaries of Legg Mason, Inc. (“Legg Mason”).

LMPFA provides administrative and certain oversight services to the Fund. The Fund pays LMPFA an investment management fee, calculated daily and paid monthly, at an annual rate of 0.65% of the Fund’s average daily net assets.

LMPFA delegates to Western Asset the day-to-day portfolio management of the Fund. Western Singapore, Western Japan and Western Asset Limited provide certain advisory services to the Fund relating to currency transactions and investment in non-U.S. dollar denominated debt securities. For its services, LMPFA pays Western Asset 70% of the net management fee it receives from the Fund. In turn, Western Asset pays Western Singapore, Western Japan and Western Asset Limited a fee for their services at no additional expense to the Fund. Each of Western Singapore, Western Japan and Western Asset Limited receives a fee from Western Asset, payable monthly, in an amount equal to 70% of the Fund’s fee paid to LMPFA by the Fund related to the Fund’s assets that Western Asset allocates to Western Singapore, Western Japan and Western Asset Limited, respectively, to manage.

All officers and one Director of the Fund are employees of Legg Mason or its affiliates and do not receive compensation from the Fund.

Western Asset Investment Grade Defined Opportunity Trust Inc. 2012 Semi-Annual Report

3. Investments

During the six months ended May 31, 2012, the aggregate cost of purchases and proceeds from sales of investments (excluding short-term investments) and U.S Government & Agency Obligations were as follows:

	Investments	U.S. Government & Agency Obligations
Purchases	$63,424,890	$24,728,757
Sales	64,319,278	24,749,948

At May 31, 2012, the aggregate gross unrealized appreciation and depreciation of investments for federal income tax purposes were substantially as follows:

Gross unrealized appreciation		$26,337,570
Gross unrealized depreciation		(1,776,897)
Net unrealized appreciation		$24,560,673

At May 31, 2012, the Fund had the following open futures contracts:

	Number of Contracts	Expiration Date	Basis Value	Market Value	Unrealized Gain (Loss)
Contracts to Buy:
U.S. Treasury 2-Year Notes	15	9/12	$ 3,304,502	$ 3,306,094	$ 1,592
U.S. Treasury 5-Year Notes	42	9/12	5,213,199	5,215,875	2,676
U.S. Treasury Ultra Long-Term Bonds	10	9/12	1,640,290	1,690,000	49,710
					53,978
Contracts to Sell:
U.S. Treasury 10-Year Notes	112	9/12	14,860,167	15,001,000	(140,833	)
U.S. Treasury 30-Year Bonds	151	9/12	22,257,564	22,607,531	(349,967	)
					(490,800	)
Net unrealized loss on open futures contracts					$(436,822	)

At May 31, 2012, the Fund had the following open forward foreign currency contracts:

Foreign Currency	Counterparty	Local Currency	Market Value	Settlement Date	Unrealized Gain
Contracts to Buy:
Euro	Citibank, N.A.	888,855	$1,099,676	8/16/12	$ 171
Contracts to Sell:
Euro	Citibank, N.A.	404,000	499,822	8/16/12	25,548
Euro	Citibank, N.A.	1,227,000	1,518,023	8/16/12	73,534
					99,082
Net unrealized gain on open forward foreign currency contracts					$99,253

Western Asset Investment Grade Defined Opportunity Trust Inc. 2012 Semi-Annual Report

Notes to financial statements (unaudited) (cont’d)

4. Derivative instruments and hedging activities

Financial Accounting Standards Board Codification Topic 815 requires enhanced disclosure about an entity’s derivative and hedging activities.

Below is a table, grouped by derivative type, that provides information about the fair value and the location of derivatives within the Statement of Assets and Liabilities at May 31, 2012.

ASSET DERIVATIVES1
	Interest Rate Risk	Foreign Exchange Risk	Total
Futures contracts2	$53,978	—	$ 53,978
Forward foreign currency contracts	—	$99,253	99,253
Total	$53,978	$99,253	$153,231

LIABILITY DERIVATIVES1
		Interest Rate Risk
Futures contracts2		$490,800

1 Generally, the balance sheet location for asset derivatives is receivables/net unrealized appreciation (depreciation) and for liability derivatives is payables/net unrealized appreciation (depreciation).

2 Includes cumulative appreciation (depreciation) of futures contracts as reported in the footnotes. Only variation margin is reported within the receivables and/or payables of the Statement of Assets and Liabilities.

The following tables provide information about the effect of derivatives and hedging activities on the Fund’s Statement of Operations for the six months ended May 31, 2012. The first table provides additional detail about the amounts and sources of gains (losses) realized on derivatives during the period. The second table provides additional information about the change in unrealized appreciation (depreciation) resulting from the Fund’s derivatives and hedging activities during the period.

AMOUNT OF REALIZED GAIN (LOSS) ON DERIVATIVES RECOGNIZED
	Interest Rate Risk		Foreign Exchange Risk	Credit Risk	Total
Futures contracts	$(1,161,263	)	—	—	$(1,161,263	)
Swap contracts	—		—	$27,427	27,427
Forward foreign currency contracts	—		$130,141	—	130,141
Total	$(1,161,263	)	$130,141	$27,427	$(1,003,695	)

Western Asset Investment Grade Defined Opportunity Trust Inc. 2012 Semi-Annual Report

CHANGE IN UNREALIZED APPRECIATION (DEPRECIATION) ON DERIVATIVES RECOGNIZED
	Interest Rate Risk		Foreign Exchange Risk	Total
Futures contracts	$(617,374	)	—	$(617,374	)
Forward foreign currency contracts	—		$47,277	47,277
Total	$(617,374	)	$47,277	$(570,097	)

During the six months ended May 31, 2012, the volume of derivative activity for the Fund was as follows:

		Average Market Value
Futures contracts (to buy)		$ 7,130,600
Futures contracts (to sell)		29,238,491
Forward foreign currency contracts (to buy)		157,097
Forward foreign currency contracts (to sell)		2,137,799

		Average Notional Balance
Credit default swap contracts (to sell protection)†		$194,286

† At May 31, 2012, there were no open positions held in this derivative.

5. Distributions subsequent to May 31, 2012

On May 10, 2012, the Fund’s Board of Directors declared three distributions, each in the amount of $0.1045 per share, payable on June 29, 2012, July 27, 2012 and August 31, 2012 to shareholders of record on June 22, 2012, July 20, 2012 and August 24, 2012, respectively.

6. Recent accounting pronouncement

In May 2011, the Financial Accounting Standards Board issued Accounting Standards Update No. 2011-04, Fair Value Measurement (Topic 820) — Amendments to Achieve Common Fair Value Measurement and Disclosure Requirements in U.S. GAAP and IFRSs (“ASU No. 2011-04”). ASU No. 2011-04 establishes common requirements for measuring fair value and for disclosing information about fair value measurements. ASU No. 2011-04 is effective during interim and annual periods beginning after December 15, 2011. Management has evaluated ASU No. 2011-04 and concluded that it does not materially impact the financial statement amounts; however, as required, additional disclosure has been included about fair value measurement.

Western Asset Investment Grade Defined Opportunity Trust Inc.

Additional shareholder information (unaudited)

Results of annual meeting of shareholders

The Annual Meeting of Shareholders of Western Asset Investment Grade Defined Opportunity Trust Inc. was held on March 30, 2012, for the purpose of considering and voting upon the election of Directors. The following table provides information concerning the matter voted upon at the meeting:

Election of directors

Nominees	Votes For	Votes Withheld
Riordan Roett	8,136,374	167,047
Jeswald W. Salacuse	8,135,970	167,451

At May 31, 2012, in addition to Riordan Roett and Jeswald W. Salacuse, the other Directors of the Fund were as follows:

Carol L. Colman
Daniel P. Cronin
Paolo M. Cucchi
Leslie H. Gelb
R. Jay Gerken
William R. Hutchinson

Western Asset Investment Grade Defined Opportunity Trust Inc.

Dividend reinvestment plan (unaudited)

Unless you elect to receive distributions in cash (i.e., opt-out), all dividends, including any capital gain dividends, on your Common Stock will be automatically reinvested by American Stock Transfer & Trust Company LLC, as agent for the stockholders (the “Plan Agent”), in additional shares of Common Stock under the Fund’s Dividend Reinvestment Plan (the “Plan”). You may elect not to participate in the Plan by contacting the Plan Agent. If you do not participate, you will receive all cash distributions paid by check mailed directly to you by American Stock Transfer & Trust Company LLC, as dividend paying agent.

If you participate in the Plan, the number of shares of Common Stock you will receive will be determined as follows:

(1) If the market price of the Common Stock on the record date (or, if the record date is not a NYSE trading day, the immediately preceding trading day) for determining stockholders eligible to receive the relevant dividend or distribution (the “determination date”) is equal to or exceeds 98% of the net asset value per share of the Common Stock, the Fund will issue new Common Stock at a price equal to the greater of (a) 98% of the net asset value per share at the close of trading on the NYSE on the determination date or (b) 95% of the market price per share of the Common Stock on the determination date.

(2) If 98% of the net asset value per share of the Common Stock exceeds the market price of the Common Stock on the determination date, the Plan Agent will receive the dividend or distribution in cash and will buy Common Stock in the open market, on the NYSE or elsewhere, for your account as soon as practicable commencing on the trading day following the determination date and terminating no later than the earlier of (a) 30 days after the dividend or distribution payment date, or (b) the record date for the next succeeding dividend or distribution to be made to the stockholders; except when necessary to comply with applicable provisions of the federal securities laws. If during this period: (i) the market price rises so that it equals or exceeds 98% of the net asset value per share of the Common Stock at the close of trading on the NYSE on the determination date before the Plan Agent has completed the open market purchases or (ii) if the Plan Agent is unable to invest the full amount eligible to be reinvested in open market purchases, the Plan Agent will cease purchasing Common Stock in the open market and the Fund shall issue the remaining Common Stock at a price per share equal to the greater of (a) 98% of the net asset value per share at the close of trading on the Exchange on the determination date or (b) 95% of the then current market price per share.

Western Asset Investment Grade Defined Opportunity Trust Inc.

Dividend reinvestment plan (unaudited) (cont’d)

Common Stock in your account will be held by the Plan Agent in non-certificated form. Any proxy you receive will include all shares of Common Stock you have received under the Plan.

You may withdraw from the Plan (i.e., opt-out) by notifying the Plan Agent in writing at 59 Maiden Lane, New York, New York 10038 or by calling the Plan Agent at 1-888-888-0151. Such withdrawal will be effective immediately if notice is received by the Plan Agent not less than ten business days prior to any dividend or distribution record date; otherwise such withdrawal will be effective as soon as practicable after the Plan Agent’s investment of the most recently declared dividend or distribution on the Common Stock. The Plan may be terminated by the Fund upon notice in writing mailed to stockholders at least 30 days prior to the record date for the payment of any dividend or distribution by the Fund for which the termination is to be effective. Upon any termination, you will be sent a certificate or certificates for the full number of shares of Common Stock held for you under the Plan and cash for any fractional share of Common Stock. You may elect to notify the Plan Agent in advance of such termination to have the Plan Agent sell part or all of your Common Stock on your behalf. You will be charged a service charge and the Plan Agent is authorized to deduct brokerage charges actually incurred for this transaction from the proceeds.

There is no service charge for reinvestment of your dividends or distributions in Common Stock. However, all participants will pay a pro rata share of brokerage commissions incurred by the Plan Agent when it makes open market purchases. Because all dividends and distributions will be automatically reinvested in additional shares of Common Stock, this allows you to add to your investment through dollar cost averaging, which may lower the average cost of your Common Stock over time. Dollar cost averaging is a technique for lowering the average cost per share over time if the Fund’s net asset value declines. While dollar cost averaging has definite advantages, it cannot assure profit or protect against loss in declining markets.

Automatically reinvesting dividends and distributions does not mean that you do not have to pay income taxes due upon receiving dividends and distributions. Investors will be subject to income tax on amounts reinvested under the Plan.

The Fund reserves the right to amend or terminate the Plan if, in the judgment of the Board of Directors, the change is warranted. There is no direct service charge to participants in the Plan; however, the Fund reserves the right to amend the Plan to include a service charge payable by the participants. Additional information about the Plan and your account may be obtained from the Plan Agent at 1-888-888-0151.

Western Asset

Investment Grade Defined Opportunity Trust Inc.

Directors	Western Asset Investment Grade Defined Opportunity Trust Inc.	Independent registered public accounting firm
Carol L. Colman		Independent registered public accounting firm
Daniel P. Cronin	620 Eighth Avenue	KPMG LLP
Paolo M. Cucchi	49th Floor	345 Park Avenue
Leslie H. Gelb	New York, NY 10018	New York, NY 10154
R. Jay Gerken
Chairman	Investment manager	Legal counsel
William R. Hutchinson	Legg Mason Partners Fund Advisor, LLC	Simpson Thacher & Bartlett LLP
Riordan Roett		425 Lexington Avenue
Jeswald W. Salacuse	Subadvisers	New York, NY 10017
	Western Asset Management Company
Officers	Western Asset Management Company Limited	New York Stock Exchange Symbol
R. Jay Gerken	Western Asset Management Company Ltd	IGI
President and Chief Executive Officer	Western Asset Management Company Pte. Ltd.
Richard F. Sennett
Principal Financial Officer	Custodian
Ted P. Becker	State Street Bank and Trust Company
Chief Compliance Officer	1 Lincoln Street
Vanessa A. Williams	Boston, MA 02111
Identity Theft Prevention Officer
Robert I. Frenkel	Transfer agent
Secretary and Chief Legal Officer	American Stock Transfer & Trust Company
Thomas C. Mandia	59 Maiden Lane
Assistant Secretary	New York, NY 10038
Steven Frank
Treasurer
Jeanne M. Kelly
Senior Vice President

Legg Mason Funds Privacy and Security Notice

Your Privacy and the Security of Your Personal Information is Very Important to the Legg Mason Funds

This Privacy and Security Notice (the “Privacy Notice”) addresses the Legg Mason Funds’ privacy and data protection practices with respect to nonpublic personal information the Funds receive. The Legg Mason Funds include any funds sold by the Funds’ distributor, Legg Mason Investor Services, LLC, as well as Legg Mason-sponsored closed-end funds and certain closed-ends funds managed or sub-advised by Legg Mason or its affiliates. The provisions of this Privacy Notice apply to your information both while you are a shareholder and after you are no longer invested with the Funds.

The Type of Nonpublic Personal Information the Funds Collect About You

The Funds collect and maintain nonpublic personal information about you in connection with your shareholder account. Such information may include, but is not limited to:

· Personal information included on applications or other forms;

· Account balances, transactions, and mutual fund holdings and positions;

· Online account access user IDs, passwords, security challenge question responses; and

· Information received from consumer reporting agencies regarding credit history and creditworthiness (such as the amount of an individual’s total debt, payment history, etc.).

How the Funds Use Nonpublic Personal Information About You

The Funds do not sell or share your nonpublic personal information with third parties or with affiliates for their marketing purposes, or with other financial institutions or affiliates for joint marketing purposes, unless you have authorized the Funds to do so. The Funds do not disclose any nonpublic personal information about you except as may be required to perform transactions or services you have authorized or as permitted or required by law. The Funds may disclose information about you to:

· Employees, agents, and affiliates on a “need to know” basis to enable the Funds to conduct ordinary business or comply with obligations to government regulators;

· Service providers, including the Funds’ affiliates, who assist the Funds as part of the ordinary course of business (such as printing, mailing services, or processing or servicing your account with us) or otherwise perform services on the Funds’ behalf, including companies that may perform marketing services solely for the Funds;

· The Funds’ representatives such as legal counsel, accountants and auditors; and

· Fiduciaries or representatives acting on your behalf, such as an IRA custodian or trustee of a grantor trust.


		NOT PART OF THE SEMI-ANNUAL REPORT

Legg Mason Funds Privacy and Security Notice (cont’d)

Except as otherwise permitted by applicable law, companies acting on the Funds’ behalf are contractually obligated to keep nonpublic personal information the Funds provide to them confidential and to use the information the Funds share only to provide the services the Funds ask them to perform.

The Funds may disclose nonpublic personal information about you when necessary to enforce their rights or protect against fraud, or as permitted or required by applicable law, such as in connection with a law enforcement or regulatory request, subpoena, or similar legal process. In the event of a corporate action or in the event a Fund service provider changes, the Funds may be required to disclose your nonpublic personal information to third parties. While it is the Funds’ practice to obtain protections for disclosed information in these types of transactions, the Funds cannot guarantee their privacy policy will remain unchanged.

Keeping You Informed of the Funds’ Privacy and Security Practices

The Funds will notify you annually of their privacy policy as required by federal law. While the Funds reserve the right to modify this policy at any time they will notify you promptly if this privacy policy changes.

The Funds’ Security Practices

The Funds maintain appropriate physical, electronic and procedural safeguards designed to guard your nonpublic personal information. The Funds’ internal data security policies restrict access to your nonpublic personal information to authorized employees, who may use your nonpublic personal information for Fund business purposes only.

Although the Funds strive to protect your nonpublic personal information, they cannot ensure or warrant the security of any information you provide or transmit to them, and you do so at your own risk. In the event of a breach of the confidentiality or security of your nonpublic personal information, the Funds will attempt to notify you as necessary so you can take appropriate protective steps. If you have consented to the Funds using electronic communications or electronic delivery of statements, they may notify you under such circumstances using the most current email address you have on record with them.

In order for the Funds to provide effective service to you, keeping your account information accurate is very important. If you believe that your account information is incomplete, not accurate or not current, or if you have questions about the Funds’ privacy practices, write the Funds using the contact information on your account statements, email the Funds by clicking on the Contact Us section of the Funds’ website at www.leggmason.com, or contact the Fund at 1-888-777-0102.

Revised April 2011


		NOT PART OF THE SEMI-ANNUAL REPORT

Western Asset Investment Grade Defined Opportunity Trust Inc.

Western Asset Investment Grade Defined Opportunity Trust Inc.
620 Eighth Avenue
49th Floor
New York, NY 10018

Notice is hereby given in accordance with Section 23(c) of the Investment Company Act of 1940, as amended, that from time to time the Fund may purchase at market price shares of its common stock in the open market.

The Fund files its complete schedule of portfolio holdings with the Securities and Exchange Commission (“SEC”) for the first and third quarters of each fiscal year on Form N-Q. The Fund’s Forms N-Q are available on the SEC’s website at www.sec.gov. The Fund’s Forms N-Q may be reviewed and copied at the SEC’s Public Reference Room in Washington, D.C., and information on the operation of the Public Reference Room may be obtained by calling 1-800-SEC-0330. To obtain information on Form N-Q from the Fund, shareholders can call 1-888-777-0102.

Information on how the Fund voted proxies relating to portfolio securities during the prior 12-month period ended June 30th of each year and a description of the policies and procedures that the Fund uses to determine how to vote proxies related to portfolio transactions are available (1) without charge, upon request, by calling 1-888-777-0102, (2) on the Fund’s website at www.lmcef.com and (3) on the SEC’s website at www.sec.gov.

This report is transmitted to the shareholders of Western Asset Investment Grade Defined Opportunity Trust Inc. for their information. This is not a prospectus, circular or representation intended for use in the purchase of shares of the Fund or any securities mentioned in this report.

American Stock
Transfer & Trust Company
59 Maiden Lane
New York, NY 10038

WASX012742 7/12 SR12-1691

ITEM 2. CODE OF ETHICS.

Not applicable.

ITEM 3. AUDIT COMMITTEE FINANCIAL EXPERT.

Not applicable.

ITEM 4. PRINCIPAL ACCOUNTANT FEES AND SERVICES.

Not applicable.

ITEM 5. AUDIT COMMITTEE OF LISTED REGISTRANTS.

Not Applicable.

ITEM 6. SCHEDULE OF INVESTMENTS.

Included herein under Item 1.

ITEM 7. DISCLOSURE OF PROXY VOTING POLICIES AND PROCEDURES FOR CLOSED-END MANAGEMENT INVESTMENT COMPANIES.

Not applicable.

ITEM 8. PORTFOLIO MANAGERS OF CLOSED-END MANAGEMENT INVESTMENT COMPANIES.

Not applicable.

ITEM 9. PURCHASES OF EQUITY SECURITIES BY CLOSED-END MANAGEMENT INVESTMENT COMPANY AND AFFILIATED PURCHASERS.

Not applicable.

ITEM 10. SUBMISSION OF MATTERS TO A VOTE OF SECURITY HOLDERS.

Not applicable.

ITEM 11. CONTROLS AND PROCEDURES.

(a) The registrant’s principal executive officer and principal financial officer have concluded that the registrant’s disclosure controls and procedures (as defined in Rule 30a- 3(c) under the Investment Company Act of 1940, as amended (the “1940 Act”)) are effective as of a date within 90 days of the filing date of this report that includes the disclosure required by this paragraph, based on their evaluation of the disclosure controls and procedures required by Rule 30a-3(b) under the 1940 Act and 15d-15(b) under the Securities Exchange Act of 1934.

(b) There were no changes in the registrant’s internal control over financial reporting (as defined in Rule 30a-3(d) under the 1940 Act) that occurred during the second fiscal quarter of the period covered by this report that have materially affected, or are likely to materially affect the registrant’s internal control over financial reporting.

ITEM 12. EXHIBITS.

(a) (1) Not applicable.

Exhibit 99.CODE ETH

(a) (2) Certifications pursuant to section 302 of the Sarbanes-Oxley Act of 2002 attached hereto.

Exhibit 99.CERT

(b) Certifications pursuant to Section 906 of the Sarbanes-Oxley Act of 2002 attached hereto.

Exhibit 99.906CERT

SIGNATURES

Pursuant to the requirements of the Securities Exchange Act of 1934 and the Investment Company Act of 1940, the registrant has duly caused this Report to be signed on its behalf by the undersigned, there unto duly authorized.

Western Asset Investment Grade Defined Opportunity Trust Inc.

By:	/s/ R. Jay Gerken
	R. Jay Gerken
	Chief Executive Officer of
	Western Asset Investment Grade Defined Opportunity Trust Inc.

Date:	July 25, 2012

Pursuant to the requirements of the Securities Exchange Act of 1934 and the Investment Company Act of 1940, this report has been signed below by the following persons on behalf of the registrant and in the capacities and on the dates indicated.

By:	/s/ R. Jay Gerken
	R. Jay Gerken
	Chief Executive Officer of
	Western Asset Investment Grade Defined Opportunity Trust Inc.

Date:	July 25, 2012


By:	/s/ Richard F. Sennett
	Richard F. Sennett
	Principal Financial Officer of
	Western Asset Investment Grade Defined Opportunity Trust Inc.

Date:	July 25, 2012