|   | 1) | SAMSUNG HEAVY INDUSTRIES CO. LTD, a corporation of Korea, having its registered office at 34th floor, Samsung Life Insurance Seocho Tower 1321-15 Seocho­Dong, Seocho-Gu, Seoul, Korea 137-857 (hereinafter referred to as "Samsung"); and |
|--------|----|-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|

|   | 2) | OCEAN RIG UDW INC. of Majuro, Marshall Islands, which maintains a shipping office at 80 Kifisias Avenue, GR-15125 Marousi, Athens, Greece (hereinafter "Ocean Rig") |
|--------|----|---------------------------------------------------------------------------------------------------------------------------------------------------------------------|

| (A) | Pursuant to the terms of the Drillship Master Agreement and Addendum No.1, among others it was agreed for Ocean Rig to have a contractual right until 31st January 2012 (the "Option Expiry Date") to order to Samsung the construction of up to three (3) drillships (the "Drillship A", "Drillship B"and "Drillship C" and together the "Drillships") at the price and specifications set out therein and for the other terms and conditions set out therein. |
|-----|-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|

| (B) | Pursuant to the terms of the Drillship Master Agreement and Addendum No.1 the delivery dates for the Drillships are as set out in the table below: |
|-----|----------------------------------------------------------------------------------------------------------------------------------------------------|

| Drillship                   | Option Exercise Date                                                                                                                                                      | Delivery Date                                                                                                                                                             |
|-----------------------------|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| Drillship A                 | Prior to 30th September 2011                                                                                                                                              | 1st quarter 2014                                                                                                                                                          |
| Prior to 30th November 2011 | 2nd quarter 2014                                                                                                                                                          |
| Prior to 31st January 2012  | 3rd quarter 2014                                                                                                                                                          |
| Drillship B                 | Prior to 30th September 2011                                                                                                                                              | 2nd quarter 2014                                                                                                                                                          |
| Prior to 30th November 2011 | 3rd quarter 2014                                                                                                                                                          |
| Prior to 31st January 2012  | To be advised by Samsung at its reasonable discretion declaring the earliest available date based on their production schedule, always acting in good faith when doing so |
| Drillship C                 | Prior to 30th September 2011                                                                                                                                              | 3rd quarter 2014                                                                                                                                                          |
| Prior to 30th November 2011 | To be advised by Samsung at its reasonable discretion declaring the earliest available date based on their production schedule, always acting in good faith when doing so |
|                        | Prior to 31st January 2012                                                                                                                                                | To be advised by Samsung at its reasonable discretion declaring the earliest available date based on their production schedule, always acting in good faith when doing so |

----

| (C) | Samsung and Ocean Rig have now agreed for the Option Expiry Date to be extended to 2nd  April 2012. |
|-----|---------------------------------------------------------------------------------------------------------------|

| Drillship   | Delivery Date                                                                                                                                                             |
|-------------|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| Drillship A | 4th quarter 2014                                                                                                                                                          |
| Drillship B | To be advised by Samsung at its reasonable discretion declaring the earliest available date based on their production schedule, always acting in good faith when doing so |
| Drillship C | To be advised by Samsung at its reasonable discretion declaring the earliest available date based on their production schedule, always acting in good faith when doing so |

----

| For and on behalf of    |   | For and on behalf of the Builder   |
|-------------------------|--------|------------------------------------|
| OCEAN RIG UDW INC       |   | SAMSUNG HEAVY INDUSTRIES CO., LTD. |
|                    |   |                               |
|                    |   |                               |
|                    |   |                               |
| /s/ Iraklis Sbarounis   |   | /s/ Bong Jin Oh                    |
| By: Iraklis Sbarounis   |   | By: Bong Jin Oh                    |
| Title: Attorney-In-Fact |   | Title: Attorney-In-Fact            |