Exhibit 99.1

Contact Information:

Brent Stumme		Derek Brown
LoopNet, Inc.		LoopNet, Inc
Chief Financial Officer		VP, Investor Relations & Corporate Planning
415-284-4310		415-284-4310

LOOPNET, INC. ANNOUNCES SECOND QUARTER 2011
FINANCIAL RESULTS

•		Revenue growth continues, increases 12% year over year
•		Record listings and profile views
•		Premium members continue to grow
•		Property Comps hits new high

SAN FRANCISCO, CALIF. — July 27, 2011 — LoopNet, Inc. (NASDAQ: LOOP), today announced financial results for the second quarter 2011.

LoopNet’s revenue for the second quarter of 2011 was $21.6 million, compared to $20.7 million in the first quarter of 2011, and $19.4 million in the second quarter of 2010. Net income applicable to common stockholders for the second quarter of 2011 was $1.9 million or $0.04 per diluted share, compared to $3.2 million or $0.07 per diluted share in the second quarter of 2010. Net income applicable to common stockholders for the second quarter of 2011 included acquisition related costs of $0.02 per diluted share. Net income applicable to common stockholders for the second quarter of 2010 included litigation related recoveries of $0.02 per diluted share. Non-GAAP net income for the second quarter of 2011 was $4.9 million or $0.11 per diluted share, compared to $4.2 million or $0.10 per diluted share in the second quarter of 2010. The effective tax rate for the second quarter of 2011 was 22.1% compared to 36.8% in the second quarter of 2010.

LoopNet’s Adjusted EBITDA (earnings before net interest and other income (expense), income taxes, depreciation, amortization, stock-based compensation, litigation related recoveries and acquisition related costs) for the second quarter of 2011 was $7.1 million, compared to $7.2 million in the second quarter of 2010.

Key operating metrics and business highlights from the second quarter of 2011 include:

•		Unique paying subscribers to one or more of LoopNet’s commercial real estate related services was 93,161, as of the end of the quarter;
•		Average monthly price paid by the company’s unique subscribers was $59.76 during the quarter;
•		LoopNet Premium Members were 71,971, as of the end of the quarter;
•		Average monthly price of LoopNet Premium Membership was $66.73 during the quarter;
•		Total commercial real estate listings active on the LoopNet marketplace were 829,021, as of the end of the quarter;
•		Total profile views of listings on the LoopNet marketplace were 79.6 million during the quarter;
•		LoopNet Registered Members, which includes Basic and Premium Members, were 5,022,106, as of the end of the quarter; and,
•		Average monthly unique visitors to LoopNet owned websites; including LoopNet.com, CityFeet.com, LandandFarm.com, LandsofAmercia.com, BizQuest.com and BizBuySell.com was approximately 2.9 million during the quarter, as reported by comScore Media Metrix.

Balance Sheet and Liquidity

As of June 30, 2011, LoopNet had $108.1 million of cash, cash equivalents and short-term investments and no debt.

Pending Merger Transaction

On April 27, 2011, LoopNet and the CoStar Group, Inc. (“CoStar”) announced the signing of a merger agreement for the acquisition of LoopNet by CoStar (the “Merger), which was approved by LoopNet’s stockholders at a special meeting on July 11, 2011. Completion of the Merger is subject to the expiration or termination of the waiting period imposed by the Hart-Scott Rodino Antitrust Improvement Act of 1976 as amended, and satisfaction or waiver of the other closing conditions specified in the merger agreement. The Merger is expected to close by the end of 2011.

Use of Non-GAAP Financial Measures

This press release includes discussions of Adjusted EBITDA, non-GAAP net income and non-GAAP net income per share, which are non-GAAP financial measures provided as a complement to results provided in accordance with accounting principles generally accepted in the United States of America (“GAAP”). The term “Adjusted EBITDA” refers to a financial measure that we define as earnings before net interest and other income (expense), income taxes, depreciation, amortization, stock-based compensation, litigation related recoveries and acquisition related costs. The term “non-GAAP net income” refers to a financial measure that we define as net income before stock-based compensation, litigation related recoveries, acquisition related costs and amortization of acquired intangible assets. Non-GAAP net income is also provided on a per share basis, using shares outstanding at the relevant period of measurement. Adjusted EBITDA, non-GAAP net income and non-GAAP net income per share are not substitutes for measures determined in accordance with GAAP, and may not be comparable to Adjusted EBITDA, non-GAAP net income and non-GAAP net income per share as reported by other companies. We believe Adjusted EBITDA to be relevant and useful information to our investors as this measure is an integral part of our internal management reporting and planning process and is the primary measure used by our management to evaluate the operating performance of our business. The components of Adjusted EBITDA include the key revenue and expense items for which our operating managers are responsible and upon which we evaluate their performance, and we also use Adjusted EBITDA for planning purposes and in presentations to our board of directors. We believe non-GAAP net income and non-GAAP net income per share to be relevant and useful

information to our investors as they provide meaningful insight into the Company’s performance while excluding infrequent and non-recurring items that may not be considered directly related to our on-going business operations. We believe that non-GAAP net income and non-GAAP net income per share are also used by companies and investors to evaluate comparable performance in the online marketplace and platform industry. We also believe that Adjusted EBITDA, non-GAAP net income and non-GAAP net income per share allow for a more accurate comparison of our operating results over historical periods. A limitation of Adjusted EBITDA, non-GAAP net income and non-GAAP net income per share is that they do not include all items that impact our net income for the period. Management compensates for this limitation by also relying on the comparable GAAP financial measure of net income, which includes the items that are excluded from Adjusted EBITDA, non-GAAP net income and non-GAAP net income per share. Management believes that these non-GAAP measures should be considered as a complement to, and not as a substitute for, or superior to, the corresponding measures calculated in accordance with GAAP. A reconciliation of these non-GAAP measures to GAAP is provided in the attached tables.

About LoopNet, Inc.

LoopNet operates the most heavily trafficked commercial real estate marketplace online with more than 5 million registered members and more than 2 million unique monthly visitors, as reported by Google Analytics.

The LoopNet marketplace covers all commercial property categories, including office, industrial, retail, multifamily (apartment properties for sale), hotel, land, specialty properties, investment properties and businesses for sale. LoopNet customers include virtually all of the top commercial real estate firms in the U.S., including Apartment Realty Advisors, Cassidy Turley, CB Richard Ellis, Coldwell Banker Commercial, Colliers International, Cushman & Wakefield, Grubb & Ellis, Jones Lang LaSalle, Lincoln Property Company, NAI Global, Newmark Knight Frank, ProLogis, The Shopping Center Group and Sperry Van Ness.

Forward Looking Statements

This release contains forward-looking statements regarding our financial results and the Merger. These statements are based on current information and expectations that are inherently subject to change and involve a number of risks and uncertainties. Actual events or results might differ materially from those in any forward-looking statement due to various factors, including, but not limited to, the risk that LoopNet and CoStar will be unable to comply promptly with the request for additional information received from the Federal Trade Commission on June 30, 2011 and discussed in LoopNet’s Current Reports on Form 8-K filed with the SEC on July 1, 2011; the possibility that the Merger does not close, including, but not limited to, due to the failure to obtain governmental clearances or approvals; the risk of business disruption relating to the Merger; economic events or trends in the commercial real estate market or in general, the effects of recent economic and consumer confidence trends on global and domestic financial markets, including credit available to real estate purchasers, our ability to continue to attract and retain new registered members, convert registered members into premium members and retain such premium members, seasonality, our ability to manage our growth, our ability to successfully integrate the technologies, operations and personnel of acquired businesses in a timely manner, our ability to obtain the expected strategic and financial benefits from acquisitions, our ability to introduce new or upgraded products or services and customer acceptance of such services and our ability to obtain or retain listings from commercial real estate brokers, agents and property owners. Additional information concerning factors that could cause actual events or results to differ materially from those in any forward looking statement are contained in our Annual Report on Form 10-K and Quarterly Reports on Form 10-Q filed with the Securities and Exchange Commission (“SEC”), and other SEC filings made by us. Copies of filings made by us with the SEC are available on the SEC’s website or at http://investor.loopnet.com/sec.cfm. LoopNet does not intend to update the forward-looking statements included in this press release which are based on information available to us as of the date of this release.

LOOPNET, INC.
CONDENSED CONSOLIDATED BALANCE SHEETS
(In thousands, except share data)

		December 31,				June 30,
		2010				2011
						(unaudited)
Assets
Current assets:
Cash and cash equivalents		$	88,773			$	104,559
Short-term investments			3,512				3,543
Accounts receivable, net of allowance of $236 and $206, respectively			1,494				1,911
Prepaid expenses and other current assets			1,095				2,875
Deferred income taxes			1,317				1,315
Total current assets			96,191				114,203
Property and equipment, net			2,010				3,725
Goodwill			41,507				41,507
Intangibles, net			8,940				7,658
Deferred income taxes, net, non-current			17,134				15,687
Deposits and other noncurrent assets			6,208				6,711
Total assets		$	171,990			$	189,491
Liabilities and stockholders’ equity
Current liabilities:
Accounts payable		$	471			$	700
Accrued liabilities and other current liabilities			3,393				3,914
Accrued compensation and benefits			3,522				3,183
Deferred revenue			8,888				9,458
Total current liabilities			16,274				17,255
Other long-term liabilities			2,491				2,789
Commitments and contingencies
Series A convertible preferred stock			48,546				48,715
Stockholders’ equity:
Common stock, $.001 par value, 125,000,000 shares authorized; 32,183,836 and 33,312,906
shares outstanding, respectively			40				41
Additional paid in capital			132,019				144,400
Other comprehensive loss			(389	)			(382	)
Treasury stock, at cost, 7,682,261 and 7,682,962 shares, respectively			(86,220	)			(86,227	)
Retained earnings			59,229				62,900
Total stockholders’ equity			104,679				120,732
Total liabilities and stockholders’ equity		$	171,990			$	189,491

LOOPNET, INC.
CONDENSED CONSOLIDATED STATEMENTS OF INCOME
(In thousands, except per share data)
(unaudited)

		Three months ended June 30,								Six months ended June 30,
		2010				2011				2010				2011
Revenues		$	19,364			$	21,619			$	38,186			$	42,332
Cost of revenue (1)			3,001				3,193				5,848				6,350
Gross margin			16,363				18,426				32,338				35,982
Operating expenses:
Sales and marketing (1)			4,191				5,234				8,481				10,367
Technology and product development (1)			2,948				3,852				5,896				7,511
General and administrative (1)			3,244				5,776				7,615				10,700
Amortization of acquired intangible assets			481				641				926				1,282
Total operating expenses			10,864				15,503				22,918				29,860
Income from operations			5,499				2,923				9,420				6,122
Interest and other (expense) income, net			(264	)			(358	)			(368	)			(676	)
Income before tax			5,235				2,565				9,052				5,446
Income tax expense			1,929				566				3,346				1,605
Net income			3,306				1,999				5,706				3,841
Convertible preferred stock accretion of discount			(85	)			(85	)			(170	)			(170	)
Net income applicable to common stockholders		$	3,221			$	1,914			$	5,536			$	3,671
Net income per share applicable to common stockholders:
Basic		$	0.08			$	0.05			$	0.13			$	0.09
Diluted		$	0.07			$	0.04			$	0.13			$	0.09
Shares used in per share calculation:
Basic			41,340				40,373				41,652				40,104
Diluted			43,159				44,024				43,192				42,933

(1) Stock-based compensation is allocated as follows:
Cost of revenue		$	154			$	130			$	282			$	260
Sales and marketing			444				493				929				1,078
Technology and product development			684				684				1,367				1,485
General and administrative			810				789				1,637				1,784
Total		$	2,092			$	2,096			$	4,215			$	4,607

LOOPNET, INC.
CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS
(In thousands)
(unaudited)

		Six months ended June 30,
		2010				2011
Cash flows from operating activities:
Net income		$	5,706			$	3,841
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization expense			1,649				2,024
Stock-based compensation			4,215				4,607
Tax benefits from exercise of stock options			(377	)			(113	)
Deferred income taxes			(783	)			1,449
Changes in operating assets and liabilities, net of effects of acquisitions:
Accounts receivable			(422	)			(418	)
Prepaid expenses and other assets			(1,644	)			(1,199	)
Accounts payable			(42	)			229
Accrued expenses and other liabilities			110				817
Accrued compensation and benefits			(172	)			(339	)
Deferred revenue			(27	)			570
Net cash provided by operating activities			8,213				11,468
Cash flows from investing activities:
Purchase of property and equipment			(848	)			(2,451	)
Purchase of investments			(2,985	)			(1,000	)
Acquisitions, net of acquired cash			(9,930	)			—
Net cash used in investing activities			(13,763	)			(3,451	)
Cash flows from financing activities:
Net proceeds from exercise of stock options			456				8,145
Tax withholdings related to net share settlements of restrcted stock units			(168	)			(482	)
Repurchase of common stock			(23,675	)			(7	)
Tax benefits from exercise of stock options			377				113
Net cash provided by (used in) financing activities			(23,010	)			7,769
Net increase (decrease) in cash and cash equivalents			(28,560	)			15,786
Cash and cash equivalents at beginning of the period			125,571				88,773
Cash and cash equivalents at end of the period		$	97,011			$	104,559

LOOPNET, INC.
Reconciliation of GAAP Net Income to Adjusted EBITDA
(In thousands, except per share data)

		Three months ended June 30,								Six months ended June 30,
		2010				2011				2010				2011
GAAP net income		$	3,306			$	1,999			$	5,706			$	3,841
Add back (deduct):
Income tax expense			1,929				566				3,346				1,605
Depreciation and amortization			832				1,029				1,649				2,024
Interest and other expense (income), net			264				358				368				676
Stock-based compensation			2,092				2,096				4,215				4,607
Litigation related recoveries			(1,186	)			—				(1,186	)			—
Acquisition related costs			—				1,032				—				1,280
Adjusted EBITDA		$	7,237			$	7,080			$	14,098			$	14,033

Reconciliation of GAAP Net Income to Non-GAAP Net Income
(In thousands, except per share data)

		Three months ended June 30,								Six months ended June 30,
		2010				2011				2010				2011
GAAP net income		$	3,306			$	1,999			$	5,706			$	3,841
Add back (deduct):
Stock-based compensation			2,092				2,096				4,215				4,607
Litigation related recoveries			(1,186	)			—				(1,186	)			—
Acquisition related costs			—				1,032				—				1,280
Amortization of acquired intangible assets			481				641				926				1,282
Income taxes associated with non-GAAP adjustments			(511	)			(833	)			(1,462	)			(2,115	)
Non-GAAP net income		$	4,182			$	4,935			$	8,199			$	8,895
Diluted non-GAAP net income per share		$	0.10			$	0.11			$	0.19			$	0.21
Shares used in non-GAAP diluted net income per share calculation			43,159				44,024				43,192				42,933