Radisys (RSYS) SC 13D/A Radisys Corp

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C.  20549

SCHEDULE 13D

Under the Securities Exchange Act of 1934

(Amendment No. 10)

RADISYS CORPORATION (RSYS)

(Name of Issuer)

Common Stock

(Title of Class of Securities)

750459109

(CUSIP Number)

David Nierenberg

The D3 Family Funds

19605 NE 8th Street

Camas, WA  98607

(360) 604-8600

With a copy to:

Christopher P. Davis

Kleinberg, Kaplan, Wolff & Cohen, P.C.

551 Fifth Avenue

New York, NY 10176

(212) 986-6000

(Name, Address and Telephone Number of Person

Authorized to Receive Notices and Communications)

January 17, 2014

(Date of Event which Requires Filing of this Statement)

If the filing person has previously filed a statement on Schedule 13G to report the acquisition that is the subject of this Schedule 13D and is filing this schedule because of §§ 240.13d-1(e), 240.13d-1(f) or 240.13d-1(g), check the following box Ô.

1	NAME OF REPORTING PERSONS The D3 Family Fund, L.P.
2	CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP (See Instructions) (a)[X] (b)[  ]
3	SEC USE ONLY
4	SOURCE OF FUNDS (See Instructions) WC
5	CHECK BOX IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED PURSUANT TO ITEMS 2(d) or 2(e) [   ]
6	CITIZENSHIP OR PLACE OF ORGANIZATION Washington
NUMBER OF SHARES BENEFICIALLY		7	SOLE VOTING POWER 0
OWNED BY EACH REPORTING		8	SHARED VOTING POWER 731,135 Common shares (2.5%)
PERSON WITH		9	SOLE DISPOSITIVE POWER 0
		10	SHARED DISPOSITIVE POWER 731,135
11	AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON For the reporting person listed on this page, 731,135; for all reporting persons as a group, 4,542,629 shares (15.6%)
12	CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES CERTAIN SHARES (See Instructions) Ô
13	PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11) For the reporting person listed on this page, 2.5%; for all reporting persons as a group, 15.6%.
14	TYPE OF REPORTING PERSON (See Instructions) PN

1	NAME OF REPORTING PERSONS The D3 Family Bulldog Fund, L.P.
2	CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP (See Instructions) (a)[X] (b)[  ]
3	SEC USE ONLY
4	SOURCE OF FUNDS (See Instructions) WC
5	CHECK BOX IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED PURSUANT TO ITEMS 2(d) or 2(e) [   ]
6	CITIZENSHIP OR PLACE OF ORGANIZATION Washington
NUMBER OF SHARES BENEFICIALLY		7	SOLE VOTING POWER 0
OWNED BY EACH REPORTING		8	SHARED VOTING POWER 2,753,920 common shares (9.5%)
PERSON WITH		9	SOLE DISPOSITIVE POWER 0
		10	SHARED DISPOSITIVE POWER 2,753,920
11	AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON For the reporting person listed on this page, 2,753,920 shares; for all reporting persons as a group, 4,542,629 shares (15.6%)
12	CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES CERTAIN SHARES (See Instructions) Ô
13	PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11) For the reporting person listed on this page, 9.5%; for all reporting persons as a group, 15.6%.
14	TYPE OF REPORTING PERSON PN

1	NAME OF REPORTING PERSONS The D3 Family Canadian Fund, L.P.
2	CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP (See Instructions) (c)[X] (d)[  ]
3	SEC USE ONLY
4	SOURCE OF FUNDS (See Instructions) WC
5	CHECK BOX IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED PURSUANT TO ITEMS 2(d) or 2(e) [   ]
6	CITIZENSHIP OR PLACE OF ORGANIZATION Washington
NUMBER OF SHARES BENEFICIALLY		7	SOLE VOTING POWER 0
OWNED BY EACH REPORTING		8	SHARED VOTING POWER 256,398 common shares (0.9%)
PERSON WITH		9	SOLE DISPOSITIVE POWER 0
		10	SHARED DISPOSITIVE POWER 256,398
11	AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON For the reporting person listed on this page, 256,398 shares; for all reporting persons as a group, 4,542,629 shares (15.6%)
12	CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES CERTAIN SHARES (See Instructions) Ô
13	PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11) For the reporting person listed on this page, 0.9%; for all reporting persons as a group, 15.6%.
14	TYPE OF REPORTING PERSON PN

1	NAME OF REPORTING PERSONS The DIII Offshore Fund, L.P.
2	CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP (See Instructions) (a)[X] (b)[  ]
3	SEC USE ONLY
4	SOURCE OF FUNDS (See Instructions) WC
5	CHECK BOX IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED PURSUANT TO ITEMS 2(d) or 2(e) [   ]
6	CITIZENSHIP OR PLACE OF ORGANIZATION Bahamas
NUMBER OF SHARES BENEFICIALLY		7	SOLE VOTING POWER 0
OWNED BY EACH REPORTING		8	SHARED VOTING POWER 801,176 common shares (2.8%)
PERSON WITH		9	SOLE DISPOSITIVE POWER 0
		10	SHARED DISPOSITIVE POWER 801,176
11	AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON For the reporting person listed on this page, 801,176 shares; for all reporting persons as a group, 4,542,629 shares (15.6%)
12	CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES CERTAIN SHARES (See Instructions) Ô
13	PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11) For the reporting person listed on this page, 2.8%; for all reporting persons as a group, 15.6%.
14	TYPE OF REPORTING PERSON PN

1	NAME OF REPORTING PERSONS Nierenberg Investment Management Company, Inc.
2	CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP (See Instructions) (a)[X] (b)[  ]
3	SEC USE ONLY
4	SOURCE OF FUNDS (See Instructions) WC
5	CHECK BOX IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED PURSUANT TO ITEMS 2(d) or 2(e) [   ]
6	CITIZENSHIP OR PLACE OF ORGANIZATION Washington
NUMBER OF SHARES BENEFICIALLY		7	SOLE VOTING POWER 0
OWNED BY EACH REPORTING		8	SHARED VOTING POWER 4,542,629 shares (15.6%)
PERSON WITH		9	SOLE DISPOSITIVE POWER 0
		10	SHARED DISPOSITIVE POWER 4,542,629 shares
11	AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON For the reporting person listed on this page, 4,542,629; for all reporting persons as a group, 4,542,629 shares (15.6 %)
12	CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES CERTAIN SHARES (See Instructions) Ô
13	PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11) For the reporting person listed on this page, 15.6%; for all reporting persons as a group, 15.6%.
14	TYPE OF REPORTING PERSON CO

1	NAME OF REPORTING PERSONS Nierenberg Investment Management Offshore, Inc.
2	CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP (See Instructions) (a)[X] (b)[  ]
3	SEC USE ONLY
4	SOURCE OF FUNDS (See Instructions) WC
5	CHECK BOX IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED PURSUANT TO ITEMS 2(d) or 2(e) [   ]
6	CITIZENSHIP OR PLACE OF ORGANIZATION Bahamas
NUMBER OF SHARES BENEFICIALLY		7	SOLE VOTING POWER 0
OWNED BY EACH REPORTING		8	SHARED VOTING POWER 801,176 common shares (2.8%)
PERSON WITH		9	SOLE DISPOSITIVE POWER 0
		10	SHARED DISPOSITIVE POWER 801,176 common shares
11	AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON For the reporting person listed on this page, 801,176 shares; for all reporting persons as a group, 4,542,629 shares (15.6%)
12	CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES CERTAIN SHARES (See Instructions) Ô
13	PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11) For the reporting person listed on this page, 2.8%; for all reporting persons as a group, 15.6%.
14	TYPE OF REPORTING PERSON CO

1	NAME OF REPORTING PERSONS David Nierenberg
2	CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP (See Instructions) (a)[X] (b)[  ]
3	SEC USE ONLY
4	SOURCE OF FUNDS (See Instructions) AF
5	CHECK BOX IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED PURSUANT TO ITEMS 2(d) or 2(e) [   ]
6	CITIZENSHIP OR PLACE OF ORGANIZATION United States of America
NUMBER OF SHARES BENEFICIALLY		7	SOLE VOTING POWER 0
OWNED BY EACH REPORTING		8	SHARED VOTING POWER 4,542,629 common shares (15.6%)
PERSON WITH		9	SOLE DISPOSITIVE POWER 0
		10	SHARED DISPOSITIVE POWER 4,542,629
11	AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON For the reporting person listed on this page, 4,542,629; for all reporting persons as a group, 4,542,629 shares (15.6%)
12	CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES CERTAIN SHARES (See Instructions) Ô
13	PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11) For the reporting person listed on this page, 15.6%; for all reporting persons as a group, 15.6%
14	TYPE OF REPORTING PERSON IN

This Amendment No.10 to Schedule 13D (this “Amendment”) amends the below-indicated items from the Schedule 13D with respect to the shares of common stock (the “Common Stock”) of Radisys Corporation. (“RSYS” or the “Company”) previously filed by or on behalf of the Reporting Persons (as defined below), as previously amended (the “Schedule 13D”), by supplementing such Items with the information below.

The names of the persons filing this Amendment (collectively, the “Reporting Persons”) are:  The D3 Family Fund, L.P. (the “Family Fund”), The D3 Family Bulldog Fund, L.P. (the “Bulldog Fund”), The D3 Family Canadian Fund, L.P. (the “Canadian Fund”), The DIII Offshore Fund, L.P. (the “Offshore Fund”), Nierenberg Investment Management Company, Inc. (“NIMCO”), Nierenberg Investment Management Offshore, Inc. (“NIMO”) and David Nierenberg (“Mr. Nierenberg”).

Item 4.  Purpose of Transaction

After nearly three years of serving on Radisys’ board of directors, I resigned from the board effective January 17, 2014.

When I first joined the board, I wanted changes in the company’s governance, executive leadership, corporate and business unit strategies, and cost structure.  I am comfortable leaving the board today because of the progress Radisys has made addressing those concerns:

-the board is more capable because it added several directors with relevant telecom experience, appointed strong new chairs for each standing committee, and focused its time on the identification of, and free-wheeling deliberation about, the most important issues facing the company;

-corporate strategy and resource allocation decisions are being made in a far more selective and accountable manner than they were before;

-to execute that strategy, extensive changes have been made in the company’s management team, and in its compensation, resulting, I believe, in the strongest team, and the best and most accountable decision-making process, that I’ve seen in the time that we have been a shareholder of the company;

-as a result of these strategy and the management changes, Radisys has reduced its costs by nearly 35% since late 2011.

While none of these actions assure the success of the company, and while I believe that most of them are not yet reflected in Radisys’ share price, I believe that they are substantively correct and that they are building the value of the company.  Because of the solid progress which Radisys has made addressing the reasons why I joined its board, I no longer believe that I need to serve on the board. I believe that I am leaving it in good hands. I thank Radisys for the opportunity to serve and hope that it will be successful.

Item 5.  Interest in Securities of the Issuer

(a, b)           The Reporting Persons, in the aggregate, beneficially own 4,542,629 Shares, constituting approximately 15.6% of the outstanding Shares.

SIGNATURE

After reasonable inquiry and to the best of my knowledge and belief, each of the undersigned certifies that the information set forth in the Statement is true, complete and correct.

D3 Family Fund, L.P., D3 Family Bulldog

Fund, L.P., and D3 Family Canadian Fund, L.P.

By: Nierenberg Investment Management

Company, Inc.

Its: General Partner

January 21, 2014 By: /s/ David Nierenberg

---------------------- -------------------------------------------

David Nierenberg, President

DIII Offshore Fund, L.P.

By: Nierenberg Investment Management

Offshore, Inc.

Its: General Partner

January 21, 2014 By: /s/ David Nierenberg

---------------------- -------------------------------------------

David Nierenberg, President

Nierenberg Investment Management

Company, Inc.

January 21, 2014 By: /s/ David Nierenberg

---------------------- -------------------------------------------

David Nierenberg, President

Nierenberg Investment Management

Offshore, Inc.

January 21, 2014 By: /s/ David Nierenberg

---------------------- -------------------------------------------

David Nierenberg, President

January 21, 2014 /s/ David Nierenberg

---------------------- ---------------------------------------------

David Nierenberg