SEC Form 4

FORM 4		UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 STATEMENT OF CHANGES IN BENEFICIAL OWNERSHIP Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934 or Section 30(h) of the Investment Company Act of 1940	OMB APPROVAL OMB Number: 3235-0287 Estimated average burden hours per response: 0.5
	Check this box if no longer subject to Section 16. Form 4 or Form 5 obligations may continue. See Instruction 1(b).

1. Name and Address of Reporting Person* NIERENBERG INVESTMENT MANAGEMENT CO (Last) (First) (Middle) 19605 NE 8TH STREET (Street) CAMAS WA 98607 (City) (State) (Zip)	2. Issuer Name and Ticker or Trading Symbol RADISYS CORP [ RSYS ]	5. Relationship of Reporting Person(s) to Issuer (Check all applicable) Director X 10% Owner Officer (give title below) Other (specify below)
	3. Date of Earliest Transaction (Month/Day/Year) 08/06/2007
	4. If Amendment, Date of Original Filed (Month/Day/Year)	6. Individual or Joint/Group Filing (Check Applicable Line) Form filed by One Reporting Person X Form filed by More than One Reporting Person

Table I - Non-Derivative Securities Acquired, Disposed of, or Beneficially Owned
1. Title of Security (Instr. 3)	2. Transaction Date (Month/Day/Year)	2A. Deemed Execution Date, if any (Month/Day/Year)	3. Transaction Code (Instr. 8)		4. Securities Acquired (A) or Disposed Of (D) (Instr. 3, 4 and 5)			5. Amount of Securities Beneficially Owned Following Reported Transaction(s) (Instr. 3 and 4)	6. Ownership Form: Direct (D) or Indirect (I) (Instr. 4)	7. Nature of Indirect Beneficial Ownership (Instr. 4)
			Code	V	Amount	(A) or (D)	Price
Common Stock	08/06/2007		P		15,945	A	$11.03	521,685(1)	I	By The D3 Family Fund, LP
Common Stock	08/06/2007		P		62,400	A	$11.03	1,867,771(1)	I	By The D3 Family Bulldog Fund, L.P.
Common Stock	08/06/2007		P		2,450	A	$11.03	48,048(1)	I	By The D3 Family Canadian Fund, L.P.
Common Stock	08/07/2007		P		6,000	A	$10.94	527,685(1)	I	By The D3 Family Fund, L.P.
Common Stock	08/07/2007		P		23,300	A	$10.94	1,891,071(1)	I	By The D3 Family Bulldog Fund, L.P.
Common Stock	08/07/2007		P		700	A	$10.94	48,748(1)	I	By The D3 Family Canadian Fund, L.P.
Common Stock								669,657(1)	I	By The DIII Offshore Fund, L.P.

Table II - Derivative Securities Acquired, Disposed of, or Beneficially Owned (e.g., puts, calls, warrants, options, convertible securities)
1. Title of Derivative Security (Instr. 3)	2. Conversion or Exercise Price of Derivative Security	3. Transaction Date (Month/Day/Year)	3A. Deemed Execution Date, if any (Month/Day/Year)	4. Transaction Code (Instr. 8)		5. Number of Derivative Securities Acquired (A) or Disposed of (D) (Instr. 3, 4 and 5)		6. Date Exercisable and Expiration Date (Month/Day/Year)		7. Title and Amount of Securities Underlying Derivative Security (Instr. 3 and 4)		8. Price of Derivative Security (Instr. 5)	9. Number of derivative Securities Beneficially Owned Following Reported Transaction(s) (Instr. 4)	10. Ownership Form: Direct (D) or Indirect (I) (Instr. 4)	11. Nature of Indirect Beneficial Ownership (Instr. 4)
				Code	V	(A)	(D)	Date Exercisable	Expiration Date	Title	Amount or Number of Shares

1. Name and Address of Reporting Person* NIERENBERG INVESTMENT MANAGEMENT CO (Last) (First) (Middle) 19605 NE 8TH STREET (Street) CAMAS WA 98607 (City) (State) (Zip) Relationship of Reporting Person(s) to Issuer Director X 10% Owner Officer (give title below) Other (specify below)

1. Name and Address of Reporting Person* D3 FAMILY FUND LP (Last) (First) (Middle) 19605 NE 8TH STREET (Street) CAMAS WA 98607 (City) (State) (Zip) Relationship of Reporting Person(s) to Issuer Director X 10% Owner Officer (give title below) Other (specify below)

1. Name and Address of Reporting Person* D3 Family Bulldog Fund LP (Last) (First) (Middle) 19605 NE 8TH STREET (Street) CAMAS WA 98607 (City) (State) (Zip) Relationship of Reporting Person(s) to Issuer Director X 10% Owner Officer (give title below) Other (specify below)

1. Name and Address of Reporting Person* D3 Family Canadian Fund, L.P. (Last) (First) (Middle) 19605 NE 8TH STREET (Street) CAMAS WA 98607 (City) (State) (Zip) Relationship of Reporting Person(s) to Issuer Director X 10% Owner Officer (give title below) Other (specify below)

1. Name and Address of Reporting Person* NIERENBERG DAVID (Last) (First) (Middle) 19605 SE 8TH STREET (Street) CAMAS WA 98607 (City) (State) (Zip) Relationship of Reporting Person(s) to Issuer Director X 10% Owner Officer (give title below) Other (specify below)

1. Name and Address of Reporting Person* HOOPER HENRY E (Last) (First) (Middle) 19605 NE 8TH STREET (Street) CAMAS WA 98607 (City) (State) (Zip) Relationship of Reporting Person(s) to Issuer Director X 10% Owner Officer (give title below) Other (specify below)

1. Name and Address of Reporting Person* DENVER CARA (Last) (First) (Middle) 19605 NE 8TH STREET (Street) CAMAS WA 98607 (City) (State) (Zip) Relationship of Reporting Person(s) to Issuer Director X 10% Owner Officer (give title below) Other (specify below)

Explanation of Responses:

1. Each of the reporting persons disclaims beneficial ownership of these securities except to the extent of the reporting person's pecuniary interest therein.

	David Nierenberg, President, Nierenberg Investment Management Company, Inc. (NIMCO)	08/08/2007
	David Nierenberg, President, NIMCO, General Partner of The D3 Family Fund, L.P.	08/08/2007
	David Nierenberg, President, NIMCO, General Partner of The D3 Family Bulldog Fund, L.P.	08/08/2007
	David Nierenberg, President, NIMCO, General Partner of the D3 Family Canadian Fund, L.P.	08/08/2007
	David Nierenberg	08/08/2007
	Henry Hooper	08/08/2007
	Denver Cara	08/08/2007
	** 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 4 (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).
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