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Document and Entity Information - shares	9 Months Ended
Document and Entity Information - shares	Sep. 30, 2011	Oct. 28, 2011
Document Information [Line Items]
Document Type	10-Q
Amendment Flag	false
Document Period End Date	Sep. 30, 2011
Document Fiscal Year Focus	2011
Document Fiscal Period Focus	Q3
Trading Symbol	ZIOP
Entity Registrant Name	ZIOPHARM ONCOLOGY INC
Entity Central Index Key	0001107421
Current Fiscal Year End Date	--12-31
Entity Filer Category	Accelerated Filer
Entity Common Stock, Shares Outstanding		68,451,324

BALANCE SHEETS - USD ($) $ in Thousands	Sep. 30, 2011	Dec. 31, 2010
Current assets:
Cash and cash equivalents	$ 118,933	$ 60,392
Collaboration receivable	79
Prepaid expenses and other current assets	1,405	424
Total current assets	120,417	60,816
Property and equipment, net	886	253
Deposits	91	87
Other non-current assets	882	364
Total assets	122,276	61,520
Current liabilities:
Accounts payable	2,160	1,031
Accrued expenses	8,789	2,538
Deferred revenue - current portion	800
Deferred rent - current portion	21	43
Total current liabilities	11,770	3,612
Deferred revenue	3,733
Deferred rent	77	44
Warrant liabilities	22,584	27,311
Total liabilities	38,164	30,967
Commitments and contingencies (note 6)
Stockholders' equity:
Preferred stock, $0.001 par value; 30,000,000 shares authorized and no shares issued and outstanding
Common stock, $0.001 par value; 250,000,000 shares authorized; 68,451,324 and 48,466,562 shares issued and outstanding at September 30, 2011 and December 31, 2010, respectively	68	48
Additional paid-in capital - common stock	244,670	131,530
Additional paid-in capital - warrants issued	13,722	22,789
Deficit accumulated during the development stage	(174,348)	(123,814)
Total stockholders' equity	84,112	30,553
Total liabilities and stockholders' equity	$ 122,276	$ 61,520

BALANCE SHEETS (Parenthetical) - $ / shares	Sep. 30, 2011	Dec. 31, 2010
Preferred stock, par value	$ 0.001	$ 0.001
Preferred stock, shares authorized	30,000,000	30,000,000
Preferred stock, shares issued	0	0
Preferred stock, shares outstanding	0	0
Common stock, par value	$ 0.001	$ 0.001
Common stock, shares authorized	250,000,000	250,000,000
Common stock, shares issued	68,451,324	48,466,562
Common stock, shares outstanding	68,451,324	48,466,562

STATEMENTS OF OPERATIONS - USD ($) $ in Thousands	3 Months Ended		9 Months Ended		97 Months Ended
STATEMENTS OF OPERATIONS - USD ($) $ in Thousands	Sep. 30, 2011	Sep. 30, 2010	Sep. 30, 2011	Sep. 30, 2010	Sep. 30, 2011
Research contract revenue	$ 200		$ 467		$ 467
Operating expenses:
Research and development, including costs of research contracts	10,667	$ 5,711	44,433	$ 9,872	116,249
General and administrative	3,742	2,789	11,017	8,313	64,828
Total operating expenses	14,409	8,500	55,450	18,185	181,077
Loss from operations	(14,209)	(8,500)	(54,983)	(18,185)	(180,610)
Other income, net	19	7	26	29	4,701
Change in fair value of warrants	13,388	(3,712)	4,423	(2,663)	1,561
Net income (loss)	$ (802)	$ (12,205)	$ (50,534)	$ (20,819)	$ (174,348)
Net income (loss) per share - basic	$ (0.01)	$ (0.26)	$ (0.77)	$ (0.48)
Net income (loss) per share - diluted	$ (0.01)	$ (0.26)	$ (0.77)	$ (0.48)
Weighted average common shares outstanding to compute net income (loss) per share - basic	68,104,934	47,426,991	65,277,084	43,333,663
Weighted average common shares outstanding to compute net income (loss) per share - diluted	68,104,934	47,426,991	65,277,084	43,333,663

STATEMENT OF CHANGES IN STOCKHOLDERS' EQUITY - 9 months ended Sep. 30, 2011 - USD ($) $ in Thousands	Total	Common Stock	Additional Paid-in Capital Common Stock	Additional Paid-in Capital Warrants	Deficit Accumulated During the Development Stage
Beginning Balance (in shares) at Dec. 31, 2010		48,466,562
Beginning Balance at Dec. 31, 2010	$ 30,553	$ 48	$ 131,530	$ 22,789	$ (123,814)
Stock-based compensation	1,900		1,900
Exercise of employee stock options (in shares)		460,887
Exercise of employee stock options	904		904
Exercise of warrants to purchase common stock (in shares)		2,377,571
Exercise of warrants to purchase common stock	12,703	$ 2	21,768	(9,067)
Issuance of restricted common stock		75,000
Repurchase of shares of common stock (in shares)		(15,190)
Repurchase of shares of common stock	(78)		(78)
Forfeiture of unvested restricted common stock (in shares)		(16,667)
Forfeiture of unvested restricted common stock
Net loss	(50,534)				(50,534)
Ending Balance (in shares) at Sep. 30, 2011		68,451,324
Ending Balance at Sep. 30, 2011	84,112	$ 68	244,670	$ 13,722	$ (174,348)
Issuance of common stock (in shares) \| Securities Offering		11,040,000
Issuance of common stock (in shares) \| Collaboration Agreement		6,063,161
Issuance of common stock \| Securities Offering	59,806	$ 11	59,795
Issuance of common stock \| Collaboration Agreement	$ 28,858	$ 7	$ 28,851

STATEMENT OF CHANGES IN STOCKHOLDERS' EQUITY (Parenthetical) $ in Thousands	9 Months Ended
	Sep. 30, 2011 USD ($)
Securities Offering
Issuance of common stock, commissions and expenses	$ 245
Collaboration Agreement
Issuance of common stock, commissions and expenses	$ 86

STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	9 Months Ended		97 Months Ended
STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	Sep. 30, 2011	Sep. 30, 2010	Sep. 30, 2011
Cash flows from operating activities:
Net loss	$ (50,534)	$ (20,819)	$ (174,348)
Adjustments to reconcile net loss to net cash used in operating activities:
Depreciation and amortization	172	153	1,821
Stock-based compensation	1,900	3,198	14,441
Change in fair value of warrants	(4,423)	2,663	(1,561)
Common stock issued in exchange for in-process research and development	17,457		17,457
Loss on disposal of fixed assets			9
(Increase) decrease in:
Collaboration receivable	(79)		(79)
Prepaid expenses and other current assets	(981)	3	(1,405)
Other noncurrent assets	(518)	(67)	(882)
Deposits	(4)	(41)	(91)
Increase (decrease) in:
Accounts payable	1,129	(703)	2,160
Accrued expenses	6,251	1,717	8,789
Deferred revenue	4,533		4,533
Deferred rent	12	(15)	98
Net cash used in operating activities	(25,085)	(13,911)	(129,058)
Cash flows from investing activities:
Purchases of property and equipment	(806)	(128)	(2,717)
Proceeds from sale of property and equipment			1
Net cash used in investing activities	(806)	(128)	(2,716)
Cash flows from financing activities:
Stockholders' capital contribution			500
Proceeds from exercise of stock options	904	225	1,267
Payments to employees for repurchase of common stock	(78)	(1,429)	(2,126)
Proceeds from exercise of warrants	12,399	71	12,750
Proceeds from issuance of common stock and warrants, net	71,207	32,804	221,556
Proceeds from issuance of preferred stock, net			16,760
Net cash provided by financing activities	84,432	31,671	250,707
Net increase (decrease) in cash and cash equivalents	58,541	17,632	118,933
Cash and cash equivalents, beginning of period	60,392	48,839
Cash and cash equivalents, end of period	118,933	66,471	118,933
Supplementary disclosure of cash flow information:
Cash paid for interest
Cash paid for income taxes
Supplementary disclosure of noncash investing and financing activities:
Warrants issued to placement agents and investors			47,276
Exercise of liability-classified warrants to common shares	303	49	352
Convertible Preferred Stock
Supplementary disclosure of noncash investing and financing activities:
Preferred stock conversion/exercise of equity-classified warrants to common stock			16,760
Warrant
Supplementary disclosure of noncash investing and financing activities:
Preferred stock conversion/exercise of equity-classified warrants to common stock	$ 9,067	$ 257	$ 9,324

Business

9 Months Ended

Sep. 30, 2011

Business

1. Business

Overview

ZIOPHARM Oncology, Inc. (“ZIOPHARM” or the “Company”) is a biopharmaceutical company that seeks to acquire, develop and commercialize, on its own or with other commercial partners, products for the treatment of important unmet medical needs in cancer.

The Company has had limited operations to date and its activities have consisted primarily of raising capital and conducting research and development. Accordingly, the Company is considered to be in the development stage at September 30, 2011. The Company's fiscal year ends on December 31.

The Company has operated at a loss since its inception in 2003 and has minimal revenues. The Company anticipates that losses will continue for the foreseeable future. At September 30, 2011, the Company’s accumulated deficit was approximately $174.3 million. The Company currently believes that it has sufficient capital to fund development and commercialization activities into early 2013. The Company’s ability to continue operations after its current cash resources are exhausted depends on its ability to obtain additional financing or achieve profitable operations, as to which no assurances can be given. Cash requirements may vary materially from those now planned because of changes in the Company’s focus and direction of its research and development programs, competitive and technical advances, patent developments, regulatory changes or other developments. Additional financing will be required to continue operations after the Company exhausts its current cash resources and to continue its long-term plans for clinical trials and new product development. There can be no assurance that any such financing can be realized by the Company, or if realized, what the terms thereof may be, or that any amount that the Company is able to raise will be adequate to support the Company’s working capital requirements until it achieves profitable operations.

Basis of Presentation

The accompanying unaudited interim financial statements have been prepared in accordance with the instructions to Form 10-Q pursuant to the rules and regulations of the Securities and Exchange Commission. Certain information and note disclosures required by generally accepted accounting principles (“GAAP”) in the United States of America have been condensed or omitted pursuant to such rules and regulations.

It is management’s opinion that the accompanying unaudited interim financial statements reflect all adjustments (which are normal and recurring) that are necessary for a fair statement of the results for the interim periods. The unaudited interim financial statements should be read in conjunction with the audited financial statements and the notes thereto for the year ended December 31, 2010 included in the Company’s Form 10-K for such fiscal year.

The year-end balance sheet data was derived from the audited financial statements but does not include all disclosures required by GAAP.

The results disclosed in the Statements of Operations for the three and nine months ended September 30, 2011 are not necessarily indicative of the results to be expected for the full fiscal year.

Use of Estimates

The preparation of financial statements in conformity with GAAP requires the Company to make estimates and judgments that affect the reported amounts of assets, liabilities and expenses, and related disclosure of contingent liabilities at the dates of the financial statements. Actual amounts may differ from these estimates.

Subsequent Events

The Company evaluated all events or transactions that occurred after the balance sheet date through the date these financial statements were available to be issued. During this period, the Company did not have any material recognizable or disclosable subsequent events.

Summary of Significant Accounting Policies

9 Months Ended

Sep. 30, 2011

Summary of Significant Accounting Policies

2. Summary of Significant Accounting Policies

Other than the policy below, our significant accounting policies were identified in the Company’s Form 10-K for the fiscal year ended December 31, 2010.

Revenue Recognition

The Company receives revenue from a collaboration agreement (see Note 3). Collaboration arrangements typically include payments for one or more of the following: non-refundable, upfront license fees, funding of research and development efforts, milestone payments if specified objectives are achieved and/or profit-sharing or royalties on product sales. Arrangements containing multiple elements are divided into separate units of accounting if certain criteria are met, including whether the delivered element has stand-alone value to the collaborative partner. The consideration received is then allocated among the separate units based on their respective fair values and the applicable revenue recognition criteria are applied to each of the separate units.

Revenue from non-refundable, upfront research and development fees is reported as research and development revenue and is recognized on a straight-line basis over the contracted or estimated period of performance, which is typically the development term. Research and development funding is earned over the period of effort.

Milestone payments are recognized as research and development revenue upon achievement of the milestone only if (1) the milestone payment is non-refundable, (2) substantive effort is involved in achieving the milestone and (3) the amount of the milestone is reasonable in relation to the effort expended or the risk associated with achievement of the milestone. If any of these conditions are not met, the milestone payment is deferred and recognized as revenue over the estimated remaining period of performance under the contract as the Company completes its performance obligations.

Collaborations and Alliances

9 Months Ended

Sep. 30, 2011

Collaborations and Alliances

3. Collaborations and Alliances

On March 7, 2011, the Company entered into a License and Collaboration Agreement with Solasia Pharma K.K. (“Solasia”).

Pursuant to the License and Collaboration Agreement (the “Agreement”), the Company granted Solasia an exclusive license to develop and commercialize darinaparsin (Zinapar™ or ZIO-101) in both intravenous and oral forms and related organic arsenic molecules, in all indications for human use in a pan-Asian/Pacific territory comprised of Japan, China, Hong Kong, Macau, Republic of Korea, Taiwan, Singapore, Australia, New Zealand, Malaysia, Indonesia, Philippines and Thailand.

As consideration for the license, the Company received an upfront payment of $5 million to be used exclusively for further clinical development of darinaparsin outside of the pan-Asian/Pacific territory, and will be entitled to receive additional payments of up to $32.5 million in development-based milestones and up to $53.5 million in sales-based milestones. The Company will also be entitled to receive double digit royalty payments from Solasia based upon net sales of licensed products in the applicable territories, once commercialized, and a percentage of sublicense revenues generated by Solasia.

The upfront payment for research and development funding is earned over the period of effort. The Company currently estimates this period to be 75 months, which could be adjusted in the future.

Under the Agreement, the Company provides Solasia with drug product to conduct clinical trials. These transfers are accounted for as a reduction of research and development costs and an increase in collaboration receivables.

The Agreement provides that Solasia will be responsible for the development and commercialization of darinaparsin in the pan-Asian/Pacific territory.

Fair Value Measurements

9 Months Ended

Sep. 30, 2011

Fair Value Measurements

4. Fair Value Measurements

The Company accounts for fair value measurements of its financial assets and liabilities and non-financial assets and non-financial liabilities, except those that are recognized or disclosed in the financial statements at fair value on a recurring basis. The accounting standard defines fair value, establishes a framework for measuring fair value under generally accepted accounting principles and enhances disclosures about fair value measurements. Fair value is defined as the exchange price that would be received for an asset or paid to transfer a liability (an exit price) in the principal or most advantageous market for the asset or liability in an orderly transaction between market participants on the measurement date. Valuation techniques used to measure fair value must maximize the use of observable inputs and minimize the use of unobservable inputs. The standard describes a fair value hierarchy based on three levels of inputs, of which the first two are considered observable and the last unobservable, that may be used to measure fair value which are the following:

Level 1 - Quoted prices in active markets for identical assets or liabilities.

Level 2 - Inputs other than Level 1 that are observable, either directly or indirectly, such as quoted prices for similar assets or liabilities; quoted prices in markets that are not active; or other inputs that are observable or can be corroborated by observable market data for substantially the full term of the assets or liabilities.

Level 3 - Unobservable inputs that are supported by little or no market activity and that are significant to the fair value of the assets or liabilities.

Assets and liabilities measured at fair value on a recurring basis as of September 30, 2011 and December 31, 2010 are as follows:

($ in thousands)	Fair Value Measurements at Reporting Date Using
			Quoted Prices in
			Active Markets for
			Identical		Significant Other		Significant
	Balance as of		Assets/Liabilities		Observable Inputs		Unobservable
Description	September 30, 2011		(Level 1)		(Level 2)		Inputs (Level 3)

Cash equivalents	$	117,641	$	117,641	$	-	$	-

Warrant liability	$	22,584	$	-	$	22,584	$	-

($ in thousands)	Fair Value Measurements at Reporting Date Using
			Quoted Prices in
			Active Markets for
			Identical		Significant Other		Significant
	Balance as of		Assets/Liabilities		Observable Inputs		Unobservable
Description	December 31, 2010		(Level 1)		(Level 2)		Inputs (Level 3)

Cash equivalents	$	59,219	$	59,219	$	-	$	-

Warrant liability	$	27,311	$	-	$	27,311	$	-

The warrants were valued using a Black-Scholes valuation model. See Note 7 for additional disclosures on the valuation methodology and significant assumptions.

- Definition

The entire disclosure for the fair value of financial instruments (as defined), including financial assets and financial liabilities (collectively, as defined), and the measurements of those instruments as well as disclosures related to the fair value of non-financial assets and liabilities. Such disclosures about the financial instruments, assets, and liabilities would include: (1) the fair value of the required items together with their carrying amounts (as appropriate); (2) for items for which it is not practicable to estimate fair value, disclosure would include: (a) information pertinent to estimating fair value (including, carrying amount, effective interest rate, and maturity, and (b) the reasons why it is not practicable to estimate fair value; (3) significant concentrations of credit risk including: (a) information about the activity, region, or economic characteristics identifying a concentration, (b) the maximum amount of loss the entity is exposed to based on the gross fair value of the related item, (c) policy for requiring collateral or other security and information as to accessing such collateral or security, and (d) the nature and brief description of such collateral or security; (4) quantitative information about market risks and how such risks are managed; (5) for items measured on both a recurring and nonrecurring basis information regarding the inputs used to develop the fair value measurement; and (6) for items presented in the financial statement for which fair value measurement is elected: (a) information necessary to understand the reasons for the election, (b) discussion of the effect of fair value changes on earnings, (c) a description of [similar groups] items for which the election is made and the relation thereof to the balance sheet, the aggregate carrying value of items included in the balance sheet that are not eligible for the election; (7) all other required (as defined) and desired information.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 133
-Paragraph 44A, 44B
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 107
-Paragraph 15C, 15D
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 107
-Paragraph 15A
-Subparagraph a-d
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 107
-Paragraph 15B
-Subparagraph a, b
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 5: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 107
-Paragraph 3, 10, 14, 15
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 6: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 157
-Paragraph 32, 33, 34
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 7: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 159
-Paragraph 17-22, 27, 28
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 8: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=6925170&loc=d3e19207-110258

Reference 9: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 21
-URI http://asc.fasb.org/extlink&oid=6947722&loc=d3e13537-108611

Reference 10: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 28
-URI http://asc.fasb.org/extlink&oid=6957238&loc=d3e14064-108612

Reference 11: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 10
-URI http://asc.fasb.org/extlink&oid=6947722&loc=d3e13433-108611

Reference 12: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 30
-URI http://asc.fasb.org/extlink&oid=6957238&loc=d3e14172-108612

Reference 13: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 16
-URI http://asc.fasb.org/extlink&oid=6947722&loc=d3e13504-108611

Reference 14: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
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+ Details

Earnings (Loss) per Share

9 Months Ended

Sep. 30, 2011

Earnings (Loss) per Share

5. Earnings (Loss) per Share

Basic earnings (loss) per share is computed by dividing net income (loss) by the weighted-average number of common shares outstanding for the period. Diluted earnings (loss) per share is computed using the weighted-average number of common shares outstanding during the period, plus the dilutive effect of outstanding options and warrants, using the treasury stock method and the average market price of our common stock during the applicable period.

	For the Three Months						For the Nine Months
	Ended September 30,						Ended September 30,
in thousands, except share and per share data	2011			2010			2011			2010
Basic
Net income (loss)	$	(802	)	$	(12,205	)	$	(50,534	)	$	(20,819	)
Weighted-average common shares outstanding		68,104,934			47,426,991			65,227,084			43,333,663
Earnings (loss) per share, basic	$	(0.01	)	$	(0.26	)	$	(0.77	)	$	(0.48	)

Certain shares related to some of the Company's outstanding common stock options, unvested restricted stock and warrants have not been included in the computation of diluted earnings (loss) per share for the three and nine months ended September 30, 2011 and 2010 as the result would be anti-dilutive. Such potential common shares at September 30, 2011 and 2010 consist of the following:

	For the Three Months				For the Nine Months
	Ended September 30,				Ended September 30,
	2011		2010		2011		2010
Stock options		4,981,398		3,528,852		4,981,398		3,528,852
Unvested restricted common stock		298,752		518,334		298,752		518,334
Warrants		13,179,885		15,924,642		13,179,885		15,924,642
		18,460,035		19,971,828		18,460,035		19,971,828

Commitments and Contingencies

9 Months Ended

Sep. 30, 2011

Commitments and Contingencies

6. Commitments and Contingencies

Patent and Technology License Agreement—The University of Texas M. D. Anderson Cancer Center and the Texas A&M University System.

On August 24, 2004, the Company entered into a patent and technology license agreement with The Board of Regents of the University of Texas System, acting on behalf of The University of Texas M. D. Anderson Cancer Center and the Texas A&M University System (collectively, the “Licensors”). Under this agreement, the Company was granted an exclusive, worldwide license to rights (including rights to U.S. and foreign patent and patent applications and related improvements and know-how) for the manufacture and commercialization of two classes of organic arsenicals (water- and lipid-based) for human and animal use. The class of water-based organic arsenicals includes darinaparsin.

As partial consideration for the license rights obtained, the Company made an upfront payment in 2004 of $125 thousand and granted the Licensors 250,487 shares of the Company’s common stock. In addition, the Company issued options to purchase an additional 50,222 shares outside the 2003 Stock Option Plan for $0.002 per share following the successful completion of certain clinical milestones, which vested with respect to 12,555 shares upon the filing of an Investigation New Drug application (“IND”) for darinaparsin in 2005 and vested with respect to another 25,111 shares upon the completion of dosing of the last patient for both Phase 1 clinical trials in 2007. The Company recorded $120 thousand of stock-based compensation expense related to the vesting in 2007. The remaining 12,556 shares will vest upon enrollment of the first patient in a multi-center pivotal clinical trial, i.e. a human clinical trial intended to provide the substantial evidence of efficacy necessary to support the filing of an approvable New Drug Application (“NDA”). In addition, the Licensors are entitled to receive certain milestone payments, including $100 thousand that was paid in 2005 upon the commencement of the Phase 1 clinical trial and $250 thousand that was paid in 2006 upon the dosing of the first patient in the ZIOPHARM-sponsored Phase 2 clinical trial for darinaparsin. The Company may be required to make additional payments upon achievement of certain other milestones in varying amounts that, on a cumulative basis, could total up to an additional $4.5 million. In addition, the Licensors are entitled to receive single digit percentage royalty payments on sales from a licensed product and will also be entitled to receive a portion of any fees that the Company may receive from a possible sublicense under certain circumstances. In addition, the Company also paid the Licensors $100 thousand in 2006 and 2007 to conduct scientific research with the Company obtaining exclusive right to all resulting intellectual property rights. The sponsored research agreements governing this research and any related extensions expired in February 2008 with no payments being made subsequent to that date.

The license agreement also contains other provisions customary and common in similar agreements within the industry, such as the right to sublicense the Company rights under the agreement. However, if the Company sublicenses its rights prior to the commencement of a pivotal study, i.e. a human clinical trial intended to provide the substantial evidence of efficacy necessary to support the filing of an approvable NDA, the Licensors will be entitled to receive a share of the payments received by the Company in exchange for the sublicense (subject to certain exceptions). The term of the license agreement extends until the expiration of all claims under patents and patent applications associated with the licensed technology, subject to earlier termination in the event of a default by the Company or the Licensors under the license agreement, or if the Company becomes bankrupt or insolvent. No milestones under the license agreement were reached or expensed during the years ended December 31, 2008, 2009 or 2010 or during the nine months ended September 30, 2011.

License Agreement with DEKK-Tec, Inc.

On October 15, 2004, the Company entered into a license agreement with DEKK-Tec, Inc. (“DEKK-Tec”), pursuant to which it was granted an exclusive, worldwide license for palifosfamide. As part of the signing of license agreement with DEKK-Tec, the Company expensed an upfront $50 thousand payment to DEKK-Tec in 2004.

In consideration for the license rights, DEKK-Tec is entitled to receive payments upon achieving certain milestones in varying amounts that, on a cumulative basis, may total $4.0 million. Of the aggregate milestone payments, most will be creditable against future royalty payments as referenced below. The Company expensed a $100 thousand milestone payment upon achieving Phase 2 milestones during the year ended December 31, 2006. Additionally, in 2004 the Company issued DEKK-Tec an option to purchase 27,616 shares of the Company’s common stock for $0.02 per share. Upon the execution of the license agreement, 6,904 shares vested and were subsequently exercised in 2005. The remaining options will vest upon certain milestone events, culminating with final U.S. Food and Drug Administration (“FDA”) approval of the first NDA submitted by the Company (or by its sublicensee) for palifosfamide. DEKK-Tec is entitled to receive single digit percentage royalty payments on the sales of palifosfamide should it be approved for commercial sale. On March 16, 2010, the Company expensed a $100 thousand milestone payment upon receiving a U.S. Patent for palifosfamide. There were no payments made during 2009. In December 2010, the Company expensed a $300 thousand milestone payment and 6,904 stock options became vested upon achieving Phase 3 milestones. The Company’s obligation to pay royalties will terminate on a country-by-country basis upon the expiration of all valid claims of patents in such country covering licensed product, subject to earlier termination in the event of a default by a party under the license agreement. No milestones under the license agreement were reached or expensed during the nine months ended September 30, 2011.

Option Agreement with Southern Research Institute

On December 22, 2004, the Company entered into an Option Agreement (the “Option Agreement”) with Southern Research Institute (“SRI”) , pursuant to which the Company was granted an exclusive option to obtain an exclusive license to SRI’s interest in certain intellectual property, including exclusive rights related to certain isophosphoramide mustard analogs.

Also on December 22, 2004, the Company entered into a Research Agreement with SRI pursuant to which the Company agreed to spend a sum not to exceed $200 thousand between the execution of the agreement and December 21, 2006, including a $25 thousand payment that was made simultaneously with the execution of the agreement, to fund research and development work by SRI in the field of isophosphoramide mustard analogs. The Option Agreement was exercised on February 13, 2007. Under the license agreement entered into upon exercise of the option, the Company is required to remit minimum annual royalty payments of $25 thousand until the first commercial sale of a licensed product. These payments were made for the years ended December 31, 2008 and 2009 and 2010. The Company may be required to make payments upon achievement of certain milestones in varying amounts which on a cumulative basis could total up to $775 thousand. In addition, SRI will be entitled to receive single digit percentage royalty payments on the sales of a licensed product in any country until all licensed patents rights in that country which are utilized in the product have expired. No milestones under the license agreement were reached or expensed during the years ended December 31, 2008, 2009 or 2010 or during the nine months ended September 30, 2011.

License Agreement with Baxter Healthcare Corporation

On November 3, 2006, the Company entered into a definitive Asset Purchase Agreement for indibulin and a License Agreement to proprietary nanosuspension technology with affiliates of Baxter Healthcare S.A. The purchase included the entire indibulin intellectual property portfolio as well as existing drug substance and capsule inventories. The terms of the Asset Purchase Agreement included an upfront cash payment of approximately $1.1 million and an additional $100 thousand payment for existing inventory, both of which were expensed in 2006. In addition to the upfront costs, the Asset Purchase Agreement includes additional diligence and milestone payments that could amount to approximately $8 million in the aggregate and royalties on net sales of products covered by a valid claim of a patent for the life of the patent on a country-by-country basis. The Company expensed a $625 thousand milestone payment upon the successful U.S. IND application for indibulin in 2007. The License Agreement requires payment of a $15 thousand annual patent and license prosecution/maintenance fee through the expiration of the last of the licensed patents which is expected to expire in 2025, and single digit royalties on net sales of licensed products covered by a valid claim of a patent for the life of the patent on a country-by-country basis. The term of the license agreement extends until the expiration of the last to expire of the patents covering the licensed products, subject to earlier termination in the event of defaults by the parties under the license agreement.

In October 2009, the License Agreement was amended to allow the Company to manufacturer indibulin. No milestones under the license agreement were reached or expensed during the years ended December 31, 2008, 2009 or 2010 or during the nine months ended September 30, 2011.

Exclusive Channel Partner Agreement with Intrexon Corporation

On January 6, 2011, the Company entered into an Exclusive Channel Partner Agreement (the “Channel Agreement”) with Intrexon Corporation (“Intrexon”) that governs a “channel partnering” arrangement in which the Company uses Intrexon’s technology directed towards in vivo expression of effectors in connection with the development of ZIN-CTI-001 and ZIN-ATI-001 and generally to research, develop and commercialize products, in each case in which DNA is administered to humans for expression of anti-cancer effectors for the purpose of treatment or prophylaxis of cancer (collectively, the “Cancer Program”). The Channel Agreement establishes committees comprised of the Company and Intrexon representatives that govern activities related to the Cancer Program in the areas of project establishment, chemistry, manufacturing and controls, clinical and regulatory matters, commercialization efforts and intellectual property.

The Channel Agreement grants the Company a worldwide license to use patents and other intellectual property of Intrexon in connection with the research, development, use, importing, manufacture, sale, and offer for sale of products involving DNA administered to humans for expression of anti-cancer effectors for the purpose of treatment or prophylaxis of cancer (“ZIOPHARM Products”). Such license is exclusive with respect to any clinical development, selling, offering for sale or other commercialization of ZIOPHARM Products, and otherwise is non-exclusive. Subject to limited exceptions, the Company may not sublicense the rights described without Intrexon’s written consent.

Under the Channel Agreement, and subject to certain exceptions, the Company is responsible for, among other things, the performance of the Cancer Program including development, commercialization and certain aspects of manufacturing of ZIOPHARM Products. Intrexon is responsible for the costs of establishing manufacturing capabilities and facilities for the bulk manufacture of products developed under the Cancer Program, certain other aspects of manufacturing and costs of discovery-stage research with respect to platform improvements and costs of filing, prosecution and maintenance of Intrexon’s patents.

Subject to certain expense allocations and other offsets provided in the Channel Agreement, the Company will pay Intrexon on a quarterly basis 50% of net profits derived in that quarter from the sale of ZIOPHARM Products, calculated on a ZIOPHARM Product-by-ZIOPHARM Product basis. The Company has likewise agreed to pay Intrexon on a quarterly basis 50% of revenue obtained in that quarter from a sublicensor in the event of a sublicensing arrangement. In addition, in partial consideration for each party’s execution and delivery of the Channel Agreement, the Company entered into a Stock Purchase Agreement with Intrexon. (See Note 8)

During the first 24 months of the agreement, either the Company or Intrexon may terminate the Channel Agreement in the event of a material breach by the other and Intrexon may terminate the Channel Agreement under certain circumstances if the Company assigns its rights under the Channel Agreement without Intrexon’s consent. Following the first 24 months of the agreement, Intrexon may also terminate the Channel Agreement if the Company fails to use diligent efforts to develop and commercialize ZIOPHARM Products or if the Company elects not to pursue the development of a Cancer Program identified by Intrexon that is a “Superior Therapy” as defined in the Channel Agreement. Also following the first 24 months of the agreement, the Company may voluntarily terminate the Channel Agreement upon 90 days written notice to Intrexon.

Upon termination of the Channel Agreement, the Company may continue to develop and commercialize any ZIOPHARM Product that, at the time of termination:

•

is being commercialized by the Company;

•

has received regulatory approval;

•

is a subject of an application for regulatory approval that is pending before the applicable regulatory authority; or

•

is the subject of at least an ongoing Phase 2 clinical trial (in the case of a termination by Intrexon due to a ZIOPHARM uncured breach or a voluntary termination by the Company), or an ongoing Phase 1 clinical trial in the Field (in the case of a termination by the Company due to an Intrexon uncured breach or a termination by Intrexon following an unconsented assignment by the Company or the Company’s election not to pursue development of a Superior Therapy).

The Company’s obligation to pay 50% of net profits or revenue described above with respect to these “retained” products will survive termination of the Channel Agreement.

Collaboration Agreement with Harmon Hill, LLC

On April 8, 2008, the Company signed a collaboration agreement for Harmon Hill, LLC (“Harmon Hill”) to provide consulting and other services for the development and commercialization of oncology therapeutics by ZIOPHARM. Under the agreement the Company has agreed to pay Harmon Hill $20 thousand per month for the consulting services and has further agreed to pay Harmon Hill (a) $500 thousand upon the first patient dosing of the Specified Drug in a pivotal trial, which trial uses a dosing Regime introduced by Harmon Hill; and (b) provided that the Specified Drug receives regulatory approval from the FDA, the European Medicines Agency or another regulatory agency for the marketing of the Specified Drug, a 1% royalty of the Company’s net sales will be awarded to Harmon Hill. If the Specified Drug is sublicensed to a third party, the agreement entitles Harmon Hill to 1% award of royalties or other payments received from a sublicense. Subject to renewal or extension by the parties, the term of the agreement was for a one year period that expired April 8, 2009. Following such expiration, the parties continued to operate under the terms of the agreement and, during 2010, the agreement was formally extended through April 8, 2011 and again through April 8, 2012. The Company expensed $240 thousand during the years ended December 31, 2009 and 2010 and $180 thousand for the nine months ended September 30, 2011 for consulting services per the aforementioned agreement. No milestones under the collaboration agreement were reached or expensed during the years ended December 31, 2008, 2009 or 2010 or during the nine months ended September 30, 2011.

CRO Services Agreement with PPD Development, L. P.

The Company and PPD Development, L.P. ("PPD") are parties to a master clinical research organization services agreement dated January 29, 2010 and a related work order dated June 25, 2010 under which PPD provides clinical research organization ("CRO") services in support of the Company's clinical trials. PPD is entitled to cumulative payments of up to $21.5 million under these arrangements, which is payable by the Company in varying amounts upon PPD achieving specified milestones. During the year ended December 31, 2010, the Company expensed $1.8 million upon contract execution and $1.1 million upon a clinical study commencement of enrollment in North America. During the nine months ended September 30, 2011, additional milestones related to commencing enrollment in Europe, Latin America and Asia along with enrollment based milestones were met and the Company recorded an aggregate $3.1 million expense.

- Definition

The entire disclosure for commitments and contingencies.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name FASB Interpretation (FIN)
-Number 14
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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 2: http://www.xbrl.org/2003/role/presentationRef
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+ Details

Warrants

9 Months Ended

Sep. 30, 2011

Warrants

7. Warrants

The Company has issued both warrants that are accounted for as liabilities and warrants that are accounted for as equity instruments. The number of warrants outstanding at September 30, 2011 and December 31, 2010 were as follows:

	September 30,		December 31,
	2011		2010

Liability-classified warrants		8,424,905		8,590,456
Equity-classified warrants		4,754,980		7,321,686

Total warrants		13,179,885		15,912,142

Liability-Classified Warrants

In May 2005, the Company issued 419,786 warrants to placement agents for services performed in connection with a 2005 private placement (the “2005 Warrants”), 11,083 of which were subsequently exercised. The remaining 408,703 warrants were originally valued at $1.6 million. Subject to certain exceptions, the 2005 Warrants provide for anti-dilution protection should common stock or common stock equivalents be subsequently issued at a price less than the exercise price of the 2005 Warrants then in effect, which was initially $4.75 per share. This provision was triggered when the Company sold stock in a 2006 private placement at $4.63 per share. Accordingly, the 2005 Warrants were re-priced at $4.69. The provision was triggered a second time upon completion of a 2009 private placement in which the Company sold stock at $1.825 per share and issued common stock purchase warrants with an exercise price of $2.04, and the 2005 Warrants were re-priced at $4.25. The provision was triggered again when the Company sold stock in a December 2009 public offering at $3.10 per share and the 2005 Warrants were re-priced at $3.93.

Also, in connection with its December 2009 public securities offering, the Company issued warrants to purchase an aggregate of 8,206,520 shares of common stock (including the investor warrants and 464,520 warrants issued to the underwriters for the offering) (the “2009 Warrants”). The 2009 Warrants issued to investors were exercisable immediately and the warrants issued to underwriters became exercisable six months after the date of issuance. The 2009 Warrants have an exercise price of $4.02 per share and have a five year term. The fair value of the 2009 Warrants was estimated at $22.9 million using a Black-Scholes model with the following assumptions: expected volatility of 105%, risk free interest rate of 2.14%, expected life of five years and no dividends.

The Company assessed whether the 2005 Warrants and the 2009 Warrants require accounting as derivatives. The Company determined that these warrants were not indexed to the Company’s own stock in accordance with accounting standards codification Topic 815, Derivatives and Hedging. As such, the Company has concluded these warrants did not meet the scope exception for determining whether the instruments require accounting as derivatives and were classified as liabilities.

The change in the fair value of the warrant liability resulted in a gain of $13.4 million and $4.4 million for the three and nine months ended September 30, 2011, respectively. The change in the fair value of the warrant liability resulted in losses of $3.7 million and $2.7 million for the three and nine months ended September 30, 2010, respectively. The change in the fair value of the warrant liability was charged to other income (expense) in the Statements of Operations. The following assumptions were used in the Black-Scholes valuation model at September 30, 2011 and 2010:

	September 30,
	2011			2010

Risk-free interest rate		0.08 - 0.47	%		0.37 - 1.01	%
Expected life in years		0.67 - 3.18			1.67 - 4.18
Expected volatility		48.9 - 95.5	%		94.9 - 101.5	%
Expected dividend yield		0			0

During the first nine months of 2011, warrant exercises were as follows:

					Common		Liability
	Equity		Liability		Stock		Reclassed		Cash
in thousands, except share data	Warrants		Warrants		Issued		to Equity		Received
Cash exercises		2,311,585		-		2,311,585			$	12,399
Cashless exercises		39,832		165,551		65,986	$	303		-
		2,351,417		165,551		2,377,571	$	303	$	12,399

During the first nine months of 2010, warrant exercises were as follows:

					Common
	Equity		Liability		Stock		Cash
in thousands, except share data	Warrants		Warrants		Issued		Received
Cash exercises		3,292		16,000		19,292	$	71
Cashless exercises		67,446		8,767		19,933		-
		70,738		24,767		39,225	$	71

- Definition

The entire disclosure for shareholders' equity, comprised of portions attributable to the parent entity and noncontrolling interest, if any, including other comprehensive income (as applicable). Including, but not limited to: (1) balances of common stock, preferred stock, additional paid-in capital, other capital and retained earnings; (2) accumulated balance for each classification of other comprehensive income and total amount of comprehensive income; (3) amount and nature of changes in separate accounts, including the number of shares authorized and outstanding, number of shares issued upon exercise and conversion, and for other comprehensive income, the adjustments for reclassifications to net income; (4) rights and privileges of each class of stock authorized; (5) basis of treasury stock, if other than cost, and amounts paid and accounting treatment for treasury stock purchased significantly in excess of market; (6) dividends paid or payable per share and in the aggregate for each class of stock for each period presented; (7) dividend restrictions and accumulated preferred dividends in arrears (in aggregate and per share amount); (8) retained earnings appropriations or restrictions, such as dividend restrictions; (9) impact of change in accounting principle, initial adoption of new accounting principle and correction of an error in previously issued financial statements; (10) shares held in trust for Employee Stock Ownership Plan (ESOP); (11) deferred compensation related to issuance of capital stock; (12) note received for issuance of stock; (13) unamortized discount on shares; (14) description, terms, and number of warrants or rights outstanding; (15) shares under subscription and subscription receivables, effective date of new retained earnings after quasi-reorganization and deficit eliminated by quasi-reorganization and, for a period of at least ten years after the effective date, the point in time from which the new retained dates; and (16) retroactive effective of subsequent change in capital structure.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher AICPA
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-Number 12
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+ Details

Common Stock

9 Months Ended

Sep. 30, 2011

Common Stock

8. Common Stock

On January 6, 2011, and in conjunction with the Company’s execution and delivery of the Channel Agreement with Intrexon, the Company entered into a Stock Purchase Agreement and Registration Rights Agreement with Intrexon. On January 12, 2011, and pursuant to that Stock Purchase Agreement, Intrexon purchased 2,426,235 shares of the Company’s common stock in a private placement for a total purchase price of $11,645,928, or $4.80 per share. The Company simultaneously issued to Intrexon an additional 3,636,926 shares of its common stock for a cash purchase price equal to the $0.001 par value of such shares, which price was deemed paid in partial consideration for the execution and delivery of the Channel Agreement. This resulted in a non-cash expense of approximately $17.5 million for the in process research and development. Under the terms of the Stock Purchase Agreement, the Company agreed to issue to Intrexon an additional 3,636,926 shares of its common stock under certain conditions upon dosing of the first patient in a ZIOPHARM-conducted Phase 2 clinical trial in the Unites States, or similar study as the parties may agree in a country other than the United States, of a product candidate that is created, produced, developed or identified directly or indirectly by us during the term of the Channel Agreement and that, subject to certain exceptions, involves DNA administered to humans for expression of anti-cancer effectors for the purpose of treatment or prophylaxis of cancer. If issued, the purchase price for such shares will be equal to the $0.001 par value of such shares, which price will be deemed paid in partial consideration for the execution and delivery of the Channel Agreement. Pursuant to the Registration Rights Agreement, the Company has agreed to file a registration statement with the SEC registering the resale of the shares that we have issued or may issue to Intrexon under the Stock Purchase Agreement.

Also under the Stock Purchase Agreement, if requested by the Company and subject to certain conditions, restrictions and limitations, Intrexon has agreed to purchase the Company’s securities in conjunction with ‘‘qualified’’ securities offerings that are conducted by the Company while the Channel Agreement remains in effect. In conjunction with a qualified offering, Intrexon has committed to purchase up to 19.99% of the securities offered and sold therein (exclusive of Intrexon’s purchase) if requested to do so by the Company. Intrexon will not be obligated to purchase securities in a ‘‘qualified’’ securities offering unless the Company is then in substantial compliance with its obligations under the Channel Agreement and, with respect to a ‘‘qualified’’ offering that is completed following January 6, 2012, the Company confirms its intent that 40% of the offering’s net proceeds shall have been spent, or in the next year will be spent, by the Company under the Channel Agreement. In the case of a ‘‘qualified’’ offering that is completed after January 6, 2012, Intrexon’s purchase commitment will be further limited to an amount equal to one-half of the proceeds spent or to be spent by the Company under the Channel Agreement. Intrexon’s aggregate purchase commitment for all future qualified offerings is capped at $50.0 million. The Company and Intrexon subsequently amended the Stock Purchase Agreement to clarify that gross proceeds from the sale of Company securities to Intrexon in a qualified offering will apply against Intrexon’s $50.0 million purchase commitment regardless of whether Intrexon participates voluntarily or at the request of the Company. As a result of Intrexon’s purchase of securities in our February 2011 public offering (see below), the remaining maximum amount of Intrexon’s equity purchase commitment is approximately $39.0 million.

On February 3, 2011, the Company entered into an underwriting agreement with Barclays Capital Inc. (“Barclays”) relating to the issuance and sale of 9,600,000 shares of the Company’s common stock in a public offering. The price to the public in the offering was $5.75 per share, and Barclays, as the sole underwriter for the offering, agreed to purchase the shares from the Company pursuant to the underwriting agreement at a purchase price of $5.425 per share. Under the terms of the underwriting agreement, the Company also granted Barclays an option, exercisable for 30 days, to purchase up to an additional 1,440,000 shares of the Company’s common stock at a purchase price of $5.425 per share. On February 8, 2011, the transactions contemplated by the underwriting agreement were completed. In connection with the closing, Barclays exercised in full its option to purchase the additional 1,440,000 shares, resulting in the Company issuing a total of 11,040,000 shares at the closing. The net proceeds from the offering were approximately $59.4 million after deducting underwriting discounts and offering expenses.

Stock-Based Compensation

9 Months Ended

Sep. 30, 2011

Stock-Based Compensation

9. Stock-Based Compensation

The Company recognized stock-based compensation expense on all employee and non-employee awards as follows:

	For the three months				For the nine months
	ended September 30,				ended September 30,
(in thousands)	2011		2010		2011		2010

Research and development, including costs of research contracts	$	264	$	199	$	540	$	613
General and administrative		322		824		1,360		2,585
Stock-based employee compensation expense	$	586	$	1,023	$	1,900	$	3,198

The Company granted 509 thousand and 1.6 million stock options during the three and nine months ended September 30, 2011 that had a weighted-average grant date fair value of $3.88 and $4.18 per share, respectively. During the three and nine months ended September 30, 2010, the Company granted 42 thousand and 197 thousand stock options that had a weighted-average grant date fair value of $2.66 and $3.42 per share, respectively.

At September 30, 2011, total unrecognized compensation costs related to unvested stock options outstanding amounted to $7.1 million. The cost is expected to be recognized over a weighted-average period of 1.77 years.

For the nine months ended September 30, 2011 and 2010, the fair value of stock options was estimated on the date of grant using a Black-Scholes option valuation model with the following assumptions:

	For the nine months ended September 30,
	2011			2010
Risk-free interest rate		1.12 -2.61	%		1.28 - 2.75	%
Expected life in years		5.77 - 6			5
Expected volatility		83.26 - 87.4	%		89.2 - 90.6	%
Expected dividend yield		0			0

Stock option activity under the Company’s stock option plan for the nine months ended September 30, 2011 is as follows:

					Weighted-
			Weighted-		Average
(in thousands, except share and per	Number of		Average Exercise		Contractual		Aggregate
share data)	Shares		Price		Term (Years)		Intrinsic Value

Outstanding, December 31, 2010		4,566,935	$	3.39

Granted		1,573,100		5.83
Exercised		460,887		1.96
Cancelled		697,750		4.91

Outstanding, September 30, 2011		4,981,398	$	4.08		7.22	$	4,485

Options exercisable, September 30, 2011		2,619,880	$	3.17		5.31	$	4,002

Options available for future grant		1,141,718

A summary of the status of unvested restricted stock for the nine months ended September 30, 2011 is as follows:

			Weighted-Average
	Number of Shares		Grant Date Fair Value
Non-vested, December 31, 2010		348,753	$	3.32
Granted		75,000		5.66
Vested		108,334		4.36
Cancelled		16,667		2.85

Non-vested, September 30, 2011		298,752	$	2.57

At September 30, 2011, total unrecognized compensation costs related to unvested restricted stock outstanding amounted to $688 thousand. The cost is expected to be recognized over a weighted-average period of 1.47 years.

- Definition

The entire disclosure for compensation-related costs for equity-based compensation, which may include disclosure of policies, compensation plan details, allocation of equity compensation, incentive distributions, equity-based arrangements to obtain goods and services, deferred compensation arrangements, employee stock ownership plan details and employee stock purchase plan details.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 123R
-Paragraph 64, 65, A240
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher AICPA
-Name Statement of Position (SOP)
-Number 93-6
-Paragraph 53
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Staff Accounting Bulletin (SAB)
-Number Topic 14

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 50
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6406099&loc=d3e25284-112666

Reference 5: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5047-113901

Reference 6: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

Reference 7: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5444-113901

Reference 8: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 40
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6418621&loc=d3e17540-113929

+ Details