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| Delaware(State or other jurisdiction ofincorporation or organization) |   | 13-4285167 (I.R.S. EmployerIdentification No.) |   |
|-----------------------------------------------------------------------|--------|-----------------------------------------------------|--------|

| Large accelerated filer                                            | o | Accelerated filer         | o |
|--------------------------------------------------------------------|---|---------------------------|---|
| Non-accelerated filer(Do not check if a smaller reporting company) | o | Smaller reporting company | x |

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| ITEM 15. | EXHIBITS, FINANCIAL STATEMENT SCHEDULES |
|----------|-----------------------------------------|

| (a) (3)        |   |                                                                                                                                                                                                                                                    |   |                                                                    |
|----------------|--------|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|--------|-------------------------------------------------------------------------|
| Exhibit Number |   | Title of Exhibit                                                                                                                                                                                                                                        |   | Method of Filing                                                        |
|           |   |                                                                                                                                                                                                                                                    |   |                                                                    |
| 3.1            |   | Articles of Formation of Ridgewood Energy M Fund, LLC dated August 2, 2004                                                                                                                                                                              |   | Incorporated by reference to the Fund's Form 10 filed on April 29, 2005 |
|           |   |                                                                                                                                                                                                                                                    |   |                                                                    |
| 3.2            |   | Limited Liability Company Agreement between Ridgewood Energy Corporation and Investors of Ridgewood Energy M Fund, LLC dated September 7, 2004                                                                                                          |   | Incorporated by reference to the Fund's Form 10 filed on April 29, 2005 |
|           |   |                                                                                                                                                                                                                                                    |   |                                                                    |
| 31.1           |   | Certification of Robert E. Swanson, Chief Executive Officer of the Fund, pursuant to Securities Exchange Act Rule 13a-14(a)                                                                                                                             |   | Filed herewith                                                          |
|           |   |                                                                                                                                                                                                                                                    |   |                                                                    |
| 31.2           |   | Certification of Kathleen P. McSherry, Chief Financial Officer of the Fund, pursuant to Securities Exchange Act Rule 13a-14(a)                                                                                                                          |   | Filed herewith                                                          |
|           |   |                                                                                                                                                                                                                                                    |   |                                                                    |
| 32             |   | Certifications pursuant to 18 U.S.C. Section 1350, as adopted pursuant to Section 906 of The Sarbanes-Oxley Act of 2002, signed by Robert E. Swanson, Chief Executive Officer of the Fund and Kathleen P. McSherry, Chief Financial Officer of the Fund |   | Filed herewith                                                          |
|           |   |                                                                                                                                                                                                                                                    |   |                                                                    |
| 99             |   | Report of Ryder Scott Company, L.P.                                                                                                                                                                                                                     |   | Filed herewith                                                          |

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|                             | RIDGEWOOD ENERGY M FUND, LLC |                                                 |
|----------------------------------|------------------------------|------------------------------------------------------|
|                             |                         |                                                 |
|                             |                         |                                                 |   |
| Date:  August 23, 2010 | By:                          | /s/ ROBERT E. SWANSON            |   |
|                             |                         | Robert E. Swanson                                    |   |
|                             |                         | Chief Executive Officer(Principal Executive Officer) |   |
|                             |                         |                                                 |   |

| Signature                            | Capacity                                                                                  | Date                  |
|--------------------------------------|-------------------------------------------------------------------------------------------|-----------------------|
|                                 |                                                                                      |  August 23, 2010 |
| /s/ ROBERT E. SWANSON                | Chief Executive Officer (Principal  Executive Officer)                          |
| Robert E. Swanson                    |                                                                                      |
|                                 |                                                                                      |                  |
|                                 |                                                                                      |                  |
| /s/ KATHLEEN P. MCSHERRY             |  Executive Vice President and Chief Financial Officer (Principal Accounting Officer) | August 23, 2010       |
| Kathleen P. McSherry                 |                                                                                      |
|                                 |                                                                                      |                  |
| RIDGEWOOD ENERGY CORPORATION         |                                                                                      |                  |
|                                 |                                                                                      |                  |
| BY:  /s/ ROBERT E. SWANSON |   Chief Executive Officer of Manager                                            | August 23, 2010       |
| Robert E. Swanson                    |                                                                                      |                  |
|                                 |                                                                                      |                  |

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