[X]

Rule 13d-1(b)

[  ]

Rule 13d-1(c)

[  ]

Rule 13d-1(d)

1

2

CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP (a) [ ] (b) [X]

3

4

Massachusetts

NUMBER OF SHARES BENEFICIALLY OWNED BY EACH REPORTING PERSON WITH

5

1,121,235

6

0

7

1,121,235

8

0

9

1,121,235

10

CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES [ ]

11

12

IA

Item 1.

(a).

Name of Issuer: Celsion Corporation

(b).

Address of Issuer's Principal Executive Offices:

10220-L Old Columbia Road

Columbia, Maryland 21046

Item 2.

(a).

Name of Person Filing:

Ironwood Investment Management, LLC

(b).

Address of Principal Business Office or, if none, Residence:

Ironwood Investment Management, LLC

21 Custom House Street, Suite 240

Boston, MA 02110

(c).

Citizenship or Place of Organization: Massachusetts

(d).

Title of Class of Securities: Common Stock

(e).

CUSIP Number: 957070105

Item 3.

If this statement is filed pursuant to sections 240.13d-1(b) or 240.13d-2(b) or (c), check whether the person filing is a:

(a)

[ ] Broker or dealer registered under section 15 of the Act (15 U.S.C. 78o);

(b)

[ ] Bank as defined in section 3(a)(6) of the Act (15 U.S.C. 78c);

(c)

[ ] Insurance company as defined in section 3(a)(19) of the Act (15 U.S.C. 78c.);

(d)

[ ] Investment company registered under section 8 of the Investment Company Act of 1940 (15 U.S.C. 80a-8);

(e)

[x] An investment adviser in accordance with section 240.13d-1(b)(1)(ii)(E);

(f)

[ ] An employee benefit plan or endowment fund in accordance with section 240.13d-1(b)(1)(ii)(F);

(g)

[ ] A parent holding company or control person in accordance with section 240.13d-1(b)(1)(ii)(G);

(h)

[ ] A savings associations as defined in section 3(b) of the Federal Deposit Insurance Act (12 U.S.C. 1813);

(i)

[ ] A church plan that is excluded from the definition of an investment company under section 3(c)(14) of the Investment Company Act of 1940 (15 U.S.C. 80a-3);

(j)

[ ] Group, in accordance with section 240.13d-1(b)(1)(ii)(J).

Item 4.

Ownership.

Provide the following information regarding the aggregate number and percentage of the class of securities of the issuer identified in Item 1.

(a).

Amount beneficially owned: 1,121,235

(b).

Percent of class: 10.3%

(c).

Number of shares as to which the person has:

(1) Sole power to vote or to direct the vote: 1,121,235

(2) Shared power to vote or to direct the vote: 0

(3) Sole power to dispose or to direct the disposition of: 1,121,235

(4) Shared power to dispose or to direct the disposition of: 0

Item 5.

Ownership of Five Percent or Less of a Class:

Not Applicable

Item 6.

Ownership of More Than Five Percent on Behalf of Another Person:

Not Applicable

Item 7.

Identification and Classification of Subsidiaries which Acquired the Security Being Reported on by the Parent Holding Company:

Not Applicable

Item 8.

Identification and Classification of Members of the Group:

Not Applicable

Item 9.

Notice of Dissolution of Group:

Not Applicable

Item 10.

Certification:

By signing below I certify that, to the best of my knowledge and belief, the securities referred to above were acquired and are held in the ordinary course of business and were not acquired and are not held for the purpose of or with the effect of changing or influencing the control of the issuer of the securities and were not acquired and are not held in connection with or as a participant in any transaction having that purpose or effect.

After reasonable inquiry and to the best of my knowledge and belief, I certify that the information set forth in this statement is true, complete and correct.

IRONWOOD INVESTMENT MANAGEMENT, LLC

Date: December 7, 2007

By:

/s/ Charles J. Daly

Charles J. Daly, Chief Compliance Officer