| OMB      APPROVAL                                                                                                                      |
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| OMB      Number:  3235-0058Expires:       April 30, 2009Estimated      average burdenhours      per response  2.50 |
| SEC      FILE NUMBER000-49674                                                                                                          |

| (Check      one): |   |       Form 10-K   Form 20-F        Form 11-K  x      Form 10-Q   Form 10-D         Form N-SAR         Form N-CSR |
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|   |   | For      Period Ended: September 30,      2007                                                                                                                                        |
|--------|--------|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
|   |   |                                                                                                                                                                                                                                                                                                                                     |   | Transition      Report on Form 10-K |
|   |   |                                                                                                                                                                                                                                                                                                                                     |   | Transition      Report on Form 20-F |
|   |   |                                                                                                                                                                                                                                                                                                                                     |   | Transition      Report on Form 11-K |
|   |   |                                                                                                                                                                                                                                                                                                                                     |   | Transition      Report on Form 10-Q |
|   |   |                                                                                                                                                                                                                                                                                                                                     |   | Transition      Report on Form N-SAR |
|   |   | For      the Transition Period Ended:                                                  |

| Read      Instruction (on back page) Before Preparing Form. Please Print or      TypeNothing      in this form shall be construed to imply that the Commission has verified      any information contained herein. |
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| PART I — REGISTRANT      INFORMATION                          |
| PDC      2001-B Limited Partnership                                 |
| Full      Name of Registrant                                        |
|                                                                |
| Former      Name if Applicable                                      |
|                                                                |
| 120      Genesis Blvd                                               |
| Address      of Principal Executive Office (Street and      Number) |
|                                                                |
| Bridgeport,      WV 26330                                           |
| City,      State and Zip Code                                       |
|                                                                |

|   |   |   |   |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                 |
|--------|--------|--------|--------|------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
|   |   | (a)    |   | The      reason described in reasonable detail in Part III of this form could not      be eliminated without unreasonable effort or expense                                                                                                                                                                                                                                                                                                                                                                                                          |
|   |   | (b)    |   | The      subject annual report, semi-annual report, transition report on      Form 10-K, Form 20-F, Form 11-K, Form N-SAR or      Form N-CSR, or portion thereof, will be filed on or before the      fifteenth calendar day following the prescribed due date; or the subject      quarterly report or transition report on Form 10-Q, or subject      distribution report on Form 10-D, or  portion thereof, will be      filed on or before the fifth calendar day following the prescribed due      date; and |
|   |   | (c)    |   | The      accountant’s statement or other exhibit required by Rule 12b-25(c)      has been attached if applicable.                                                                                                                                                                                                                                                                                                                                                                                                                         |

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|            |                                                                                    |
|-----------------|-----------------------------------------------------------------------------------------|
| (1)   | Name      and telephone number of person to contact in regard to this      notification |

| Richard      W. McCullough, Chief Financial Officer |   | 304              |   | 808-6249                |   |   |
|-----------------------------------------------------|--------|------------------|--------|-------------------------|--------|--------|
| (Name)                                              |   | (Area      Code) |   | (Telephone      Number) |   |   |

| (2)   | Have      all other periodic reports required under Section 13 or 15(d) of the      Securities Exchange Act of 1934 or Section 30 of the Investment      Company Act of 1940 during the preceding 12 months or for such      shorter period that the registrant was required to file such report(s)      been filed ? If answer is no, identify      report(s).          Yes  o  No      x                                                                                                                                                                                 |
|-----------------|-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
|            |  Form      10-K for the year ended December 31, 2005(1)Form      10-Q for the quarter ended March 31, 2006Form      10-Q for quarter ended June 30, 2006Form      10-Q for quarter ended September 30, 2006Form      10-K for the year ended December 31, 2006Form      10-Q for the quarter ended March 31, 2007Form      10-Q for quarter ended June 30, 2007Form      10-Q for quarter ended September 30, 2007 (1) The      2005 Form 10-K will be a comprehensive filing to include the restatement      of our historical financial statements for the year ended December 31,      2004, and for the interim period ended March 31, 2005. |

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|            |                                                                                                                                                                                                                                                                                                                                                |
|-----------------|-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| (3)   | Is      it anticipated that any significant change in results of operations from      the corresponding period for the last fiscal year will be reflected by the      earnings statements to be included in the subject report or portion      thereof?                Yes  o No x |

|   | If      so, attach an explanation of the anticipated change, both narratively and      quantitatively, and, if appropriate, state the reasons why a reasonable      estimate of the results cannot bemade. |
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|                                         |   |   |   |                                                                                                                            |
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| Date:  February 29,      2008 |   | By     |   | /s/ Richard W.McCullough                                                                                                        |
|                                         |   |   |   | Richard      W. McCullough,Chief      Financial Officer of Petroleum Development Corporation, the Managing      General Partner |