Note 16. Subsequent Events	12 Months Ended
Dec. 31, 2012
Subsequent Events [Text Block]	16. SUBSEQUENT EVENTS During the first quarter of 2013 thus far, we received approximately $0.4 million of gross proceeds from the exercise of warrants and options to purchase approximately 120,516 shares of the Company’s common stock. On January 18, 2013, we entered into a technology development contract with Hisun, pursuant to which Hisun paid us a non-refundable research and development fee of $5 million to support our development of ThermoDox® and we will provide research data and other technical support in relation to a regulatory filing by Hisun for approval of ThermoDox® for manufacturing and sale in mainland China, Hong Kong and Macau. Following our announcement on January 31, 2013 that the HEAT study failed to meet its primary endpoint, we and Hisun continue to collaborate and evaluate next steps in relation to ThermoDox®, which include the sub-group analysis of the Chinese cohort of patients in the Phase III clinical trial for primary liver cancer and other activities to further the development of ThermoDox® for mainland China, Hong Kong and Macau. On February 1, 2013, the Company entered into a Controlled Equity Offering SM Sales Agreement (the “ATM Agreement”) with Cantor Fitzgerald & Co., as sales agent (“Cantor”), pursuant to which Celsion may offer and sell, from time to time, through Cantor, shares of our common stock having an aggregate offering price of up to $25.0 million (the “ATM Shares”). The ATM Shares will be issued pursuant to the Company’s previously filed and effective Registration Statement on Form S-3 the base prospectus dated September 14, 2012, filed as part of such Registration Statement, and the prospectus supplement dated February 1, 2013, filed by the Company with the Securities and Exchange Commission. Under the Agreement, Cantor may sell ATM Shares by any method deemed to be an “at-the-market” offering as defined in Rule 415 promulgated under the Securities Act of 1933, as amended, including sales made directly on The NASDAQ Capital Market, on any other existing trading market for the our common stock or to or through a market maker. From February 1, 2013 through February 25, 2013, the Company has sold and issued 5,381,670 ATM shares under the ATM Agreement, receiving approximately $6.8 million in net proceeds. Celsion intends to use the net proceeds from the offering for general corporate purposes, including research and development activities, capital expenditures and working capital. The Company is not obligated to sell any ATM Shares under the ATM Agreement. Subject to the terms and conditions of the ATM Agreement, Cantor will use commercially reasonable efforts, consistent with its normal trading and sales practices and applicable state and federal law, rules and regulations and the rules of The NASDAQ Capital Market, to sell ATM Shares from time to time based upon the Company’s instructions, including any price, time or size limits or other customary parameters or conditions Celsion may impose. In addition, pursuant to the terms and conditions of the ATM Agreement and subject to the instructions of Celsion, Cantor may sell ATM Shares by any other method permitted by law, including in privately negotiated transactions. The ATM Agreement will terminate upon the earlier of (i) the sale of Shares under the ATM Agreement having an aggregate offering price of $25.0 million and (ii) the termination of the ATM Agreement by Cantor or the Company. The ATM Agreement may be terminated by Cantor or Celsion at any time upon 10 days' notice to the other party, or by Cantor at any time in certain circumstances, including the occurrence of a material adverse change in Celsion. The Company will pay Cantor a commission of 3.0% of the aggregate gross proceeds from each sale of ATM Shares and has agreed to provide Cantor with customary indemnification and contribution rights. The Company also agreed to reimburse Cantor for legal fees and disbursements, not to exceed $50,000 in the aggregate, in connection with entering into the ATM Agreement. In connection with the preferred stock offering discussed below, the Company agreed to not sell any ATM Shares for a period of one year from February 26, 2013. On February 22, 2013, the Company entered into a Securities Purchase Agreement with certain institutional investors, pursuant to which the Company agreed to sell, in a registered offering, an aggregate of 15,000.00422 shares of its Series A 0% convertible preferred stock and the warrants to purchase shares of its common stock, for an aggregate purchase price of approximately $15.0 million (the Preferred Stock Offering). The closing of the Preferred Stock Offering occurred on February 26, 2013, in which the Company received approximately $15.0 million in gross proceeds. Subject to certain ownership limitations, shares of Series A 0% convertible preferred stock are convertible, at the option of the holder thereof, into an aggregate of up to 12,072,438 shares of common stock, and the warrants are exercisable to purchase an aggregate of up to 6,036,219 shares of common stock. Each warrant has an exercise price of $1.18 per share, equal to the closing bid price of common stock on February 21, 2013. The warrants are immediately exercisable and expire five years after its issuance. As of March 15, 2013, the Company has issued an aggregate of 8,018,112 shares of common stock upon conversion of 9,963 shares of the Series A 0% convertible preferred stock.

Note 16. Subsequent Events

12 Months Ended

Dec. 31, 2012

16. SUBSEQUENT EVENTS

During the first quarter of 2013 thus far, we received approximately $0.4 million of gross proceeds from the exercise of warrants and options to purchase approximately 120,516 shares of the Company’s common stock.

On January 18, 2013, we entered into a technology development contract with Hisun, pursuant to which Hisun paid us a non-refundable research and development fee of $5 million to support our development of ThermoDox® and we will provide research data and other technical support in relation to a regulatory filing by Hisun for approval of ThermoDox® for manufacturing and sale in mainland China, Hong Kong and Macau. Following our announcement on January 31, 2013 that the HEAT study failed to meet its primary endpoint, we and Hisun continue to collaborate and evaluate next steps in relation to ThermoDox®, which include the sub-group analysis of the Chinese cohort of patients in the Phase III clinical trial for primary liver cancer and other activities to further the development of ThermoDox® for mainland China, Hong Kong and Macau.

On February 1, 2013, the Company entered into a Controlled Equity Offering SM Sales Agreement (the “ATM Agreement”) with Cantor Fitzgerald & Co., as sales agent (“Cantor”), pursuant to which Celsion may offer and sell, from time to time, through Cantor, shares of our common stock having an aggregate offering price of up to $25.0 million (the “ATM Shares”). The ATM Shares will be issued pursuant to the Company’s previously filed and effective Registration Statement on Form S-3 the base prospectus dated September 14, 2012, filed as part of such Registration Statement, and the prospectus supplement dated February 1, 2013, filed by the Company with the Securities and Exchange Commission. Under the Agreement, Cantor may sell ATM Shares by any method deemed to be an “at-the-market” offering as defined in Rule 415 promulgated under the Securities Act of 1933, as amended, including sales made directly on The NASDAQ Capital Market, on any other existing trading market for the our common stock or to or through a market maker. From February 1, 2013 through February 25, 2013, the Company has sold and issued 5,381,670 ATM shares under the ATM Agreement, receiving approximately $6.8 million in net proceeds.

Celsion intends to use the net proceeds from the offering for general corporate purposes, including research and development activities, capital expenditures and working capital. The Company is not obligated to sell any ATM Shares under the ATM Agreement. Subject to the terms and conditions of the ATM Agreement, Cantor will use commercially reasonable efforts, consistent with its normal trading and sales practices and applicable state and federal law, rules and regulations and the rules of The NASDAQ Capital Market, to sell ATM Shares from time to time based upon the Company’s instructions, including any price, time or size limits or other customary parameters or conditions Celsion may impose. In addition, pursuant to the terms and conditions of the ATM Agreement and subject to the instructions of Celsion, Cantor may sell ATM Shares by any other method permitted by law, including in privately negotiated transactions.

The ATM Agreement will terminate upon the earlier of (i) the sale of Shares under the ATM Agreement having an aggregate offering price of $25.0 million and (ii) the termination of the ATM Agreement by Cantor or the Company. The ATM Agreement may be terminated by Cantor or Celsion at any time upon 10 days' notice to the other party, or by Cantor at any time in certain circumstances, including the occurrence of a material adverse change in Celsion. The Company will pay Cantor a commission of 3.0% of the aggregate gross proceeds from each sale of ATM Shares and has agreed to provide Cantor with customary indemnification and contribution rights. The Company also agreed to reimburse Cantor for legal fees and disbursements, not to exceed $50,000 in the aggregate, in connection with entering into the ATM Agreement. In connection with the preferred stock offering discussed below, the Company agreed to not sell any ATM Shares for a period of one year from February 26, 2013.

On February 22, 2013, the Company entered into a Securities Purchase Agreement with certain institutional investors, pursuant to which the Company agreed to sell, in a registered offering, an aggregate of 15,000.00422 shares of its Series A 0% convertible preferred stock and the warrants to purchase shares of its common stock, for an aggregate purchase price of approximately $15.0 million (the Preferred Stock Offering). The closing of the Preferred Stock Offering occurred on February 26, 2013, in which the Company received approximately $15.0 million in gross proceeds. Subject to certain ownership limitations, shares of Series A 0% convertible preferred stock are convertible, at the option of the holder thereof, into an aggregate of up to 12,072,438 shares of common stock, and the warrants are exercisable to purchase an aggregate of up to 6,036,219 shares of common stock. Each warrant has an exercise price of $1.18 per share, equal to the closing bid price of common stock on February 21, 2013. The warrants are immediately exercisable and expire five years after its issuance. As of March 15, 2013, the Company has issued an aggregate of 8,018,112 shares of common stock upon conversion of 9,963 shares of the Series A 0% convertible preferred stock.