UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 13D Under the Securities Act of 1934 (Amendment No. 11) Mexican Restaurants, Inc. (Name of Issuer) Common Stock (Title of Class of Securities) 14712P104 (CUSIP Number) David Nierenberg The D3 Family Funds 19605 NE 8th Street Camas, WA 98607 360-604-8600 (Name, Address and Telephone Number of Person Authorized to Receive Notices and Communications) September 2, 2005 (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 ss.ss.240.13d-1(e), 240.13d-1(f) or 240.13d-1(g), check the following box: |_| -------------------------------------------------------------------------------- 1 NAME OF REPORTING PERSON S.S. OR I.R.S. IDENTIFICATION NOS. OF ABOVE PERSON The D3 Family Fund, L.P. (David Nierenberg is president of the General Partner, which is Nierenberg Investment Management Company.) -------------------------------------------------------------------------------- 2 CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP (a) |X| (b) |_| -------------------------------------------------------------------------------- 3 SEC USE ONLY -------------------------------------------------------------------------------- 4 SOURCE OF FUNDS 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 USA -------------------------------------------------------------------------------- 7 SOLE VOTING POWER 545,306 common shares (15.8%) ----------------------------------------------------------------- NUMBER OF 8 SHARED VOTING POWER SHARES BENEFICIALLY 0 OWNED BY ----------------------------------------------------------------- EACH 9 SOLE DISPOSITIVE POWER REPORTING PERSON 545,306 WITH ----------------------------------------------------------------- 10 SHARED DISPOSITIVE POWER 0 -------------------------------------------------------------------------------- 11 AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON 1,073,010 shares (31.1%) -------------------------------------------------------------------------------- 12 CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES CERTAIN SHARES |_| -------------------------------------------------------------------------------- 13 PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11) 31.1% -------------------------------------------------------------------------------- 14 TYPE OF REPORTING PERSON PN -------------------------------------------------------------------------------- *SEE INSTRUCTIONS BEFORE FILLING OUT! 2 -------------------------------------------------------------------------------- 1 NAME OF REPORTING PERSON S.S. OR I.R.S. IDENTIFICATION NOS. OF ABOVE PERSON The D3 Family Retirement Fund, L.P. (David Nierenberg is president of the General Partner, which is Nierenberg Investment Management Company.) -------------------------------------------------------------------------------- 2 CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP (a) |X| (b) |_| -------------------------------------------------------------------------------- 3 SEC USE ONLY -------------------------------------------------------------------------------- 4 SOURCE OF FUNDS 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 USA -------------------------------------------------------------------------------- 7 SOLE VOTING POWER 222,770 common shares (6.5%) ----------------------------------------------------------------- NUMBER OF 8 SHARED VOTING POWER SHARES BENEFICIALLY 0 OWNED BY ----------------------------------------------------------------- EACH 9 SOLE DISPOSITIVE POWER REPORTING PERSON 222,770 WITH ----------------------------------------------------------------- 10 SHARED DISPOSITIVE POWER 0 -------------------------------------------------------------------------------- 11 AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON 1,073,010 shares (31.1%) -------------------------------------------------------------------------------- 12 CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES CERTAIN SHARES |_| -------------------------------------------------------------------------------- 13 PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11) 31.1% -------------------------------------------------------------------------------- 14 TYPE OF REPORTING PERSON PN -------------------------------------------------------------------------------- *SEE INSTRUCTIONS BEFORE FILLING OUT! 3 -------------------------------------------------------------------------------- 1 NAME OF REPORTING PERSON S.S. OR I.R.S. IDENTIFICATION NOS. OF ABOVE PERSON The D3 Children's Fund, L.P. (David Nierenberg is president of the General Partner, which is Nierenberg Investment Management Company.) -------------------------------------------------------------------------------- 2 CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP (a) |X| (b) |_| -------------------------------------------------------------------------------- 3 SEC USE ONLY -------------------------------------------------------------------------------- 4 SOURCE OF FUNDS 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 USA -------------------------------------------------------------------------------- 7 SOLE VOTING POWER 48,224 common shares (1.4%) ----------------------------------------------------------------- NUMBER OF 8 SHARED VOTING POWER SHARES BENEFICIALLY 0 OWNED BY ----------------------------------------------------------------- EACH 9 SOLE DISPOSITIVE POWER REPORTING PERSON 48,224 WITH ----------------------------------------------------------------- 10 SHARED DISPOSITIVE POWER 0 -------------------------------------------------------------------------------- 11 AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON 1,073,010 shares (31.1%) -------------------------------------------------------------------------------- 12 CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES CERTAIN SHARES |_| -------------------------------------------------------------------------------- 13 PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11) 31.1% -------------------------------------------------------------------------------- 14 TYPE OF REPORTING PERSON PN -------------------------------------------------------------------------------- *SEE INSTRUCTIONS BEFORE FILLING OUT! 4 -------------------------------------------------------------------------------- 1 NAME OF REPORTING PERSON S.S. OR I.R.S. IDENTIFICATION NOS. OF ABOVE PERSON The D3 Offshore Fund, L.P. (David Nierenberg is president of the General Partner, which is Nierenberg Investment Management Company.) -------------------------------------------------------------------------------- 2 CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP (a) |X| (b) |_| -------------------------------------------------------------------------------- 3 SEC USE ONLY -------------------------------------------------------------------------------- 4 SOURCE OF FUNDS 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 USA -------------------------------------------------------------------------------- 7 SOLE VOTING POWER 202,710 common shares (5.9%) ----------------------------------------------------------------- NUMBER OF 8 SHARED VOTING POWER SHARES BENEFICIALLY 0 OWNED BY ----------------------------------------------------------------- EACH 9 SOLE DISPOSITIVE POWER REPORTING PERSON 202,710 WITH ----------------------------------------------------------------- 10 SHARED DISPOSITIVE POWER 0 -------------------------------------------------------------------------------- 11 AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON 1,073,010 shares (31.1%) -------------------------------------------------------------------------------- 12 CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES CERTAIN SHARES |_| -------------------------------------------------------------------------------- 13 PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11) 31.1% -------------------------------------------------------------------------------- 14 TYPE OF REPORTING PERSON PN -------------------------------------------------------------------------------- *SEE INSTRUCTIONS BEFORE FILLING OUT! 5 -------------------------------------------------------------------------------- 1 NAME OF REPORTING PERSON S.S. OR I.R.S. IDENTIFICATION NOS. OF ABOVE PERSON The D3 Family Bulldog Fund, L.P. ((David Nierenberg is president of the General Partner, which is Nierenberg Investment Management Company.) -------------------------------------------------------------------------------- 2 CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP (a) |X| (b) |_| -------------------------------------------------------------------------------- 3 SEC USE ONLY -------------------------------------------------------------------------------- 4 SOURCE OF FUNDS 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 USA -------------------------------------------------------------------------------- 7 SOLE VOTING POWER 54,000 common shares (1.6%) ----------------------------------------------------------------- NUMBER OF 8 SHARED VOTING POWER SHARES BENEFICIALLY 0 OWNED BY ----------------------------------------------------------------- EACH 9 SOLE DISPOSITIVE POWER REPORTING PERSON 54,000 WITH ----------------------------------------------------------------- 10 SHARED DISPOSITIVE POWER 0 -------------------------------------------------------------------------------- 11 AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON 1,073,010 shares (31.1%) -------------------------------------------------------------------------------- 12 CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES CERTAIN SHARES |_| -------------------------------------------------------------------------------- 13 PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11) 31.1% -------------------------------------------------------------------------------- 14 TYPE OF REPORTING PERSON PN -------------------------------------------------------------------------------- *SEE INSTRUCTIONS BEFORE FILLING OUT! 6 Item 1. Security and Issuer. Common stock in Mexican Restaurants, Inc. (CASA), 1135 Edgebrook, Houston, TX 77034-1899. Item 2. Identity and Background. The D3 Family Fund, L.P. is a Washington State limited partnership, whose principal business is investing in the equities of public micro-cap issuers. Located at 19605 N.E. 8th St., Camas, Washington 98607. No convictions or administrative proceedings as described in 2 (d) and (e). Item 3. Source and Amount of Funds or Other Consideration Source of funds is money invested in the partnership by its partners. Item 4. Purpose of Transaction For investment purposes. Item 5. Interest in Securities of the Issuer. (a,b) The D3 Family Fund, L.P. owns and has sole voting and dispositive power over 545,306 common shares of CASA. (c) N/A (d) N/A (e) N/A Item 6. Contracts, Arrangements, Understandings or Relationships with Respect to Securities of the Issuer. N/A Item 7. Material to be Filed as Exhibits N/A 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. September 9, 2005 /s/ DAVID NIERENBERG ----------------- -------------------- David Nierenberg President Nierenberg Investment Management Company, Inc., the General Partner of The D3 Family Fund, L.P 7 Item 1. Security and Issuer. Common stock in Mexican Restaurants, Inc. (CASA), 1135 Edgebrook, Houston, TX 77034-1899. Item 2. Identity and Background. The D3 Family Retirement Fund, L.P. is a Washington State limited partnership, whose principal Business is investing in the equities of public micro-cap issuers. Located at 19605 N.E. 8th St., Camas, Washington 98607. No convictions or administrative proceedings as described in 2 (d) and (e). Item 3. Source and Amount of Funds or Other Consideration Source of funds is money invested in the partnership by its partners. Item 4. Purpose of Transaction For investment purposes. Item 5. Interest in Securities of the Issuer. (a,b) The D3 Family Retirement Fund, L.P. owns and has sole voting and dispositive power over 222,770 common shares of CASA. (c) N/A (d) N/A (e) N/A Item 6. Contracts, Arrangements, Understandings or Relationships with Respect to Securities of the Issuer. N/A Item 7. Material to be Filed as Exhibits N/A Signature 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. September 9, 2005 /s/ DAVID NIERENBERG ----------------- -------------------- David Nierenberg President Nierenberg Investment Management Company, Inc., the General Partner of The D3 Family Fund, L.P 8 Item 1. Security and Issuer. Common stock in Mexican Restaurants, Inc. (CASA), 1135 Edgebrook, Houston, TX 77034-1899. Item 2. Identity and Background. The D3 Children's Fund, L.P. is a Washington State limited partnership, whose principal business is investing in the equities of public micro-cap Issuers. Located at 19605 N.E. 8th St., Camas, Washington 98607. No convictions or administrative proceedings as described in 2 (d) and (e). Item 3. Source and Amount of Funds or Other Consideration Source of funds is money invested in the partnership by its partners. Item 4. Purpose of Transaction For investment purposes. Item 5. Interest in Securities of the Issuer. (a,b) The D3 Children's Fund, L.P. owns and has sole voting and dispositive power over 48,224 common shares of CASA. (c) N/A (d) N/A (e) N/A Item 6. Contracts, Arrangements, Understandings or Relationships with Respect to Securities of the Issuer. N/A Item 7. Material to be Filed as Exhibits N/A 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. September 9, 2005 /s/ DAVID NIERENBERG ----------------- -------------------- David Nierenberg President Nierenberg Investment Management Company, Inc., the General Partner of The D3 Family Fund, L.P 9 Item 1. Security and Issuer. Common stock in Mexican Restaurants, Inc. (CASA), 1135 Edgebrook, Houston, TX 77034-1899. Item 2. Identity and Background. The D3 Offshore Fund, L.P. is a Washington State limited partnership, whose principal business is investing in the equities of public micro-cap issuers. Located at 19605 N.E. 8th St., Camas, Washington 98607. No convictions or administrative proceedings as described in 2 (d) and (e). Item 3. Source and Amount of Funds or Other Consideration Source of funds is money invested in the partnership by its partners. Item 4. Purpose of Transaction For investment purposes. Item 5. Interest in Securities of the Issuer. (a,b) The D3 Offshore Fund, L.P. owns and has sole voting and dispositive power over 202,710 common shares of CASA. (c) Date Shares Bought Price 8/19/2005 22,000 9.40 8/24/2005 5,100 9.31 8/30/2005 12,260 9.64 8/31/2005 350 9.68 9/02/2005 30,600 9.58 (d) N/A (e) N/A Item 6. Contracts, Arrangements, Understandings or Relationships with Respect to Securities of the Issuer. N/A Item 7. Material to be Filed as Exhibits N/A 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. September 9, 2005 /s/ DAVID NIERENBERG ----------------- -------------------- David Nierenberg President Nierenberg Investment Management Company, Inc., the General Partner of The D3 Family Fund, L.P 10 Item 1. Security and Issuer. Common stock in Mexican Restaurants, Inc. (CASA), 1135 Edgebrook, Houston, TX 77034-1899. Item 2. Identity and Background. The D3 Family Bulldog Fund, L.P. is a Washington State limited partnership, whose principal business is investing in the equities of public micro-cap issuers. Located at 19605 N.E. 8th St., Camas, Washington 98607. No convictions or administrative proceedings as described in 2 (d) and (e). Item 3. Source and Amount of Funds or Other Consideration Source of funds is money invested in the partnership by its partners. Item 4. Purpose of Transaction For investment purposes. Item 5. Interest in Securities of the Issuer. (a,b) The D3 Family Bulldog Fund, L.P. owns and has sole voting and dispositive power over 54,000 common shares of CASA. (c) N/A (d) N/A (e) N/A Item 6. Contracts, Arrangements, Understandings or Relationships with Respect to Securities of the Issuer. N/A Item 7. Material to be Filed as Exhibits N/A 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. September 9, 2005 /s/ DAVID NIERENBERG ----------------- -------------------- David Nierenberg President Nierenberg Investment Management Company, Inc., the General Partner of The D3 Family Fund, L.P 11