SEC FORM 3

SEC Form 3

FORM 3

UNITED STATES SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

INITIAL STATEMENT OF BENEFICIAL OWNERSHIP OF SECURITIES

Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934
or Section 30(h) of the Investment Company Act of 1940

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1. Name and Address of Reporting Person^*

Books Steven G

(Last)

(First)

(Middle)

1240 DEMING WAY

(Street)

MADISON

53717

(City)

(State)

(Zip)

2. Date of Event Requiring Statement (Month/Day/Year)
05/08/2007

3. Issuer Name and Ticker or Trading Symbol
TomoTherapy Inc [ TTPY ]

4. Relationship of Reporting Person(s) to Issuer
(Check all applicable)

	Director	10% Owner
X	Officer (give title below)	Other (specify below)
	Chief Operating Officer

5. If Amendment, Date of Original Filed (Month/Day/Year)

6. Individual or Joint/Group Filing (Check Applicable Line)

X	Form filed by One Reporting Person
	Form filed by More than One Reporting Person

Table I - Non-Derivative Securities Beneficially Owned
1. Title of Security (Instr. 4)	2. Amount of Securities Beneficially Owned (Instr. 4)	3. Ownership Form: Direct (D) or Indirect (I) (Instr. 5)	4. Nature of Indirect Beneficial Ownership (Instr. 5)
Common Stock	27,200	D

Table II - Derivative Securities Beneficially Owned (e.g., puts, calls, warrants, options, convertible securities)
1. Title of Derivative Security (Instr. 4)	2. Date Exercisable and Expiration Date (Month/Day/Year)		3. Title and Amount of Securities Underlying Derivative Security (Instr. 4)		4. Conversion or Exercise Price of Derivative Security	5. Ownership Form: Direct (D) or Indirect (I) (Instr. 5)	6. Nature of Indirect Beneficial Ownership (Instr. 5)
1. Title of Derivative Security (Instr. 4)	Date Exercisable	Expiration Date	Title	Amount or Number of Shares	4. Conversion or Exercise Price of Derivative Security	5. Ownership Form: Direct (D) or Indirect (I) (Instr. 5)	6. Nature of Indirect Beneficial Ownership (Instr. 5)
Options (Right to Buy)⁽¹⁾	05/08/2007	03/28/2015	Common Stock	81,600	$2.82	D
Options (Right to Buy)⁽²⁾	05/08/2007	11/17/2011	Common Stock	28,114	$3.46	D
Options (Right to Buy)⁽³⁾	05/08/2007	11/17/2011	Common Stock	26,966	$3.46	D
Options (Right to Buy)⁽⁴⁾	12/07/2008	12/07/2012	Common Stock	40,800	$6.75	D
Options (Right to Buy)⁽⁵⁾	12/07/2010	12/07/2012	Common Stock	13,600	$6.75	D

Explanation of Responses:

1. Options vest over a four-year period, with 27,200 option shares currently vested, 27,200 option shares vesting on 03/28/08 and 27,200 option shares vesting on 03/28/09.

2. Options vest over a four-year period, with 7,028 option shares currently vested, 7,029 option shares vesting on 11/17/07, 7,028 option shares vesting on 11/17/08, and 7,029 option shares vesting on 11/17/09.

3. Options vest over a four-year period, with 6,741 option shares currently vested, 6,742 option shares vesting on 11/17/07, 6,741 option shares vesting on 11/17/08, and 6,742 option shares vesting on 11/17/09.

4. Options vest over a three-year period, with 27,200 option shares vesting on 12/07/08 and 13,600 option shares vesting on 12/07/09.

5. 13,600 option shares vest on 12/07/10.

Remarks:

	/s/ Shawn D. Guse, attorney in fact	05/08/2007
	** Signature of Reporting Person	Date
Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly.
* If the form is filed by more than one reporting person, see Instruction 5 (b)(v).
** Intentional misstatements or omissions of facts constitute Federal Criminal Violations See 18 U.S.C. 1001 and 15 U.S.C. 78ff(a).
Note: File three copies of this Form, one of which must be manually signed. If space is insufficient, see Instruction 6 for procedure.
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