.
.
.
EXHIBIT 99.1
1 DIAMOND OFFSHORE DRILLING, INC. RIG STATUS REPORT AS OF AUGUST 15, 2005
<Table>
<Caption>
RIG NAME WD DESIGN LOCATION STATUS* OPERATOR CURRENT TERM DAYRATE
DOMESTIC DEEPWATER SEMISUBMERSIBLES (6) (000s)
Ocean Quest 3,500' Victory Class GOM Contracted Walter one assignment well from
Noble mid 120's
Ocean Star 5,500' Victory Class GOM Contracted Kerr-McGee 90 day term extension low 140's
Ocean America 5,500' Ocean Odyssey GOM Contracted Pioneer three wells low 150's
Ocean Valiant 5,500' Ocean Odyssey GOM Contracted Kerr-McGee one well low 130's
Ocean Victory 5,500' Victory Class GOM Contracted Shell two wells low 160's
Ocean Confidence 7,500' DP Aker H-3.2
Modified GOM Contracted BP five-year term mid 170's
DOMESTIC 2ND/3RD GENERATION SEMISUBMERSIBLES (5)
Ocean New Era 1,500' Korkut GOM Reactivating DODI - -
Ocean Voyager 2,000' Victory Class GOM Contracted ATP two wells mid 90's
Ocean Concord 2,200' F&G SS-2000 GOM Contracted Amerada Hess one well mid 120's
Ocean Lexington 2,200' F&G SS-2000 GOM Shipyard DODI - -
Ocean Saratoga 2,200' F&G SS-2000 GOM Contracted LLOG three wells mid 60's
<Caption>
EST. END
RIG NAME START DATE DATE FUTURE CONTRACTS AND OTHER INFORMATION
DOMESTIC DEEPWATER SEMISUBMERSIBLES (6)
Ocean Quest mid June 2005 late Aug. 120 day term plus option with Noble in mid 120's beginning mid June and ending mid
2005 Oct. 2005; followed by six-month term extension plus option in the low 240's
beginning in mid Oct. 2005 and ending in mid April 2006. Available; actively
marketing.
Ocean Star mid July 2005 mid Oct. 12 month extension with Kerr-McGee in mid 170's beginning mid Oct. 2005 and ending
2005 mid Oct. 2006. Available; actively marketing.
Ocean America early May 2005 early Nov. Following assignment wells with Pioneer, first of two extension wells with Mariner
2005 in mid 110's beginning early Nov.; followed by one well extension with Mariner in
mid 110's beginning early Nov. and ending late Dec. 2005; followed by second well
with Mariner in low 130's beginning late Dec. 2005 and ending mid Feb. 2006;
followed by one year term plus option with Mariner in low 230's beginning mid Feb.
2006 and ending mid Feb. 2007. Available; actively marketing.
Ocean Valiant late June 2005 mid Sept. 180 day term extension with Kerr-McGee in low 150's beginning mid Sept. 2005 and
2005 ending mid Mar. 2006; followed by one-year term extension plus option from
Kerr-McGee in low 300,000's beginning in mid Mar. 2006 and ending in mid Mar. 2007.
Available; actively marketing.
Ocean Victory early June 2005 late Aug. One well with Kerr-McGee in mid 180's beginning late Aug. and ending late Sept.;
2005 followed by one year term with Murphy in low 200's beginning late Sept. 2005 and
ending late Sept. 2006. Available; actively marketing.
Ocean Confidence early Jan. 2001 early Jan. Two-year term plus option with BP in low 280's beginning early Jan. 2006 and ending
2006 early Jan. 2008. Available; actively marketing.
DOMESTIC 2ND/3RD GENERATION SEMISUBMERSIBLES (5)
Ocean New Era - - Est. availability mid Nov. 2005; followed by six-month term with Walter in low 100's
for first 30 days and mid 120's for remainder of term beginning mid Nov. 2005 and
ending mid May 2006. Available; actively marketing.
Ocean Voyager late June 2005 early Sept. One well with Amerada Hess in low 110's beginning early Sept. and ending late Oct.;
2005 followed by LOI for one well in low 110's beginning late Oct. and ending mid Dec.;
followed by two wells plus option with Amerada Hess in mid 120's beginning mid Dec.
2005 and ending mid Mar. 2006. Available; actively marketing.
Ocean Concord late May 2005 late Aug. One well with Kerr-McGee in mid 70's beginning late Aug. and ending late Nov.;
2005 followed by one assignment well from Kerr-McGee with Woodside in mid 90's beginning
late Nov. and ending early Jan. 2006; followed by one well extension plus option
with Kerr-McGee in mid 90's beginning early Jan. 2006 and ending mid Feb.; followed
by 90-day term plus option with Tana in low 130's beginning mid Feb. and ending mid
May 2006; followed by 90-day term extension plus option in low 170's beginning mid
May and ending mid Aug. Available; actively marketing.
Ocean Lexington - late Sept. Approximately 120-day Survey and maintenance between second and third well,
2005 beginning late May and ending late Sept. Following survey, two additional wells with
Walter in low 60's beginning late Sept. and ending late Nov.; followed by LOI for
one well in mid 170's beginning in late Nov. 2005 and ending in mid Jan. 2006;
followed by one well plus option with Walter in low 80's beginning mid Jan. and
ending mid Feb. Available; actively marketing.
Ocean Saratoga mid Dec. 2004 early Sept. Two wells plus option with LLOG in low 110's beginning early Sept. 2005 and ending
2005 late Jan. 2006; followed by six month extension with LLOG in low 120's beginning
late Jan. 2006 and ending late July 2006. Available; actively marketing.
</Table>
2 DIAMOND OFFSHORE DRILLING, INC. RIG STATUS REPORT AS OF AUGUST 15, 2005
<Table>
<Caption>
RIG NAME WD DESIGN LOCATION STATUS* OPERATOR CURRENT TERM DAYRATE
DOMESTIC JACKUPS(12) (000s)
Ocean Crusader 200' Mat Cantilever GOM Contracted Unocal one well high 40's
Ocean Drake 200' Mat Cantilever GOM Contracted Chevron term contract low 60's
Ocean Champion 250' Mat Slot GOM Contracted Hunt one well mid 40's
Independent Leg
Ocean Columbia 250' Cantilever GOM Contracted Newfield 180-day term mid 50's
Independent Leg
Ocean Spartan 300' Cantilever GOM Contracted LLOG three wells plus option high 50's
Independent Leg
Ocean Spur 300' Cantilever GOM DODI - - -
Independent Leg
Ocean King 300' Cantilever GOM Contracted El Paso one well extension mid 50's
Independent Leg
Ocean Nugget 300' Cantilever GOM Contracted Houston Expl. two wells plus option low 50's
Independent Leg
Ocean Summit 300' Cantilever GOM Contracted LLOG one well extension high 50's
Independent Leg
Ocean Warwick 300' Cantilever GOM Contracted Chevron 90 day term low 70's
Independent Leg
Ocean Titan 350' Cantilever GOM Contracted BHP one well plus option mid 50's
Independent Leg
Ocean Tower 350' Cantilever GOM Contracted Chevron one well mid 50's
<Caption>
RIG NAME START DATE EST. END FUTURE CONTRACTS AND OTHER INFORMATION
DATE
DOMESTIC JACKUPS (12)
Ocean Crusader late June 2005 late Aug. Two wells plus option with Seneca in high 40's beginning late Aug. and ending mid
2005 Oct. 2005. Available; actively marketing.
Ocean Drake late July 2005 late June Indexed term contract. Available; actively marketing.
2006
Ocean Champion late June 2005 late Aug. Two well extension plus option with Hunt in low 50's beginning late Aug. and
2005 ending late Oct. 2005; followed by LOI for six-month term in mid 50's beginning
late Oct. 2005 and ending late April 2006. Available; actively marketing.
Ocean Columbia early Aug. 2005 late Jan. Available; actively marketing.
2006
Ocean Spartan late June 2005 late Sept. (Two week survey Q4, 2005). Available; actively marketing.
2005
Ocean Spur - - Maintenance/repairs late June through late Aug. 2005; followed by one well with
EOG in mid 60's beginning late Aug. and ending mid Oct. 2005.
Available; actively marketing.
Ocean King late June 2005 late Aug. One well with El Paso in mid 60's beginning late Aug. and ending early Sept.;
2005 followed by one well extension in low 60's beginning early Sept. and ending mid
Sept. 2005; followed by one well with Walter in high 60's beginning mid Sept. and
ending mid Oct. 2005. Available; actively marketing.
Ocean Nugget mid May 2005 early Sept. One well extension plus option with Houston Exploration in high 60's beginning
2005 early Sept. and ending late Oct. 2005. Available; actively marketing.
Ocean Summit late June 2005 late Aug One well extension plus option with LLOG in mid 60's beginning late Aug. and
2005 ending late Sept. 2005. Available; actively marketing.
Ocean Warwick late July 2005 early Jan. Indexed term extension. Available; actively marketing.
2006
Ocean Titan late Jan. 2005 late Aug. Three wells with Walter in mid 70's beginning late Aug. and ending late Nov. 2005;
2005 followed by six-month term with Dominion Exploration in high 70's beginning late
Nov. 2005 and ending late May 2006. Available; actively marketing.
Ocean Tower early Aug. 2005 late Aug. 180-day term extension plus option with Chevron (Part I) in high 60's beginning
2005 late Aug. and ending late Nov.; followed by Part II in high 80's beginning late
Nov.2005 and ending late Feb. 2006. Available; actively marketing.
</Table>
<Table>
<Caption>
RIG NAME WD DESIGN LOCATION STATUS* OPERATOR
INTERNATIONAL SEMISUBMERSIBLES (17)
MEXICO
Ocean Ambassador 1,100' Bethlehem SS-2000 GOM Contracted PEMEX
Ocean Whittington 1,500' Aker H-3 GOM Contracted PEMEX
Ocean Worker 3,500' F&G 9500 Enhanced Pacesetter GOM Contracted PEMEX
Ocean Yorktown 2,850' F&G SS-2000 GOM Contracted PEMEX
NORTH SEA
Ocean Nomad 1,200' Aker H-3 North Sea Contracted Talisman
Ocean Guardian 1,500' Earl & Wright Sedco
711 Series North Sea Contracted Shell
Ocean Princess 1,500' Aker H-3 North Sea Contracted Talisman
Ocean Vanguard 1,500' Bingo 3000 North Sea Contracted Statoil
AUSTRALASIA
Ocean Bounty 1,500' Victory Class Australia Contracted ConocoPhillips
Ocean Patriot 1,500' Bingo 3000 Australia Contracted Anzon
Ocean Epoch 1,640' Korkut Malaysia Contracted Murphy
Ocean General 1,640' Korkut Malaysia Contracted CTOC
Ocean Baroness 7,000' Victory Class Singapore Shipyard DODI
Ocean Rover 7,000' Victory Class Malaysia Contracted Murphy
<Caption>
FUTURE CONTRACTS
RIG NAME CURRENT TERM DAYRATE (000S) START DATE EST. END DATE AND OTHER INFORMATION
INTERNATIONAL SEMISUBMERSIBLES (17)
MEXICO
Ocean Ambassador four year term work mid 50's late July 2003 mid Dec. 2007 Available.
Ocean Whittington four year term work low 60's late July 2003 early Oct. 2006 Available.
Ocean Worker four year term work high 60's mid Aug. 2003 late July 2007 Available.
Ocean Yorktown four year term work mid 40's late Oct. 2003 mid July 2007 Available.
NORTH SEA
Ocean Nomad one year low 80's early Jan. 2005 late Jan. 2006 One year extension with
Talisman in mid 150's beginning
late Jan. 2006 and ending late
Jan. 2007. Available; actively
marketing.
Ocean Guardian one year low 80's late Mar. 2005 late Mar. 2006 One-year term extension plus
option with Shell in low 160's
beginning late Mar. 2006 and
ending late Mar. 2007. (40-day
survey Q3, 2005). Available;
actively marketing.
Ocean Princess one year extension low 80's early Jan. 2005 late Dec. 2005 Two year extension with
Talisman plus option in low
150's beginning in late Dec.
2005 and ending in late Dec.
2007. Available; actively
marketing.
Ocean Vanguard one year term low 140's late May 2005 early Sept. 2006 One year plus option program in
Norway with Statoil in low
140's beginning in late May
2005 and ending in early Sept.
2006 (time period to include
one well redrill with ENI in
low 140's beginning late July
and ending late Oct. 2005).
Available; actively marketing.
AUSTRALASIA
Ocean Bounty two wells mid 80's late June 2005 mid Oct. 2005 One well with Coogee Res. in
mid 80's beginning mid Oct. and
ending mid Nov.; followed by
two wells plus option with
Coogee in low 90's beginning
mid Nov. 2005. and ending mid
Jan. 2006; followed by LOI for
one well plus option in mid
90's beginning mid Jan. and
ending mid Mar.; followed by
four wells plus option in high
90's with Woodside beginning
mid Mar. 2006 and ending mid
Sept. 2006. Available; actively
marketing.
Ocean Patriot one well high 70's late July 2005 late Sept. 2005 One well with Bass Straits in
high 70's, early Sept.-mid
Sept.; followed by one well
with Bass Straits in high
130's, mid Sept.-late Sept.;
followed by one well with
Apache in high 70's, late
Sept.-mid Oct.; followed by one
assignmnet well with Nexus in
low 150's, mid Oct.-late Dec.
2005; followed by 10-day survey
ending mid-Jan. 2006; followed
by first of four Anzon options
in mid 130's, mid Jan. 2006-mid
Feb.; followed by second of
four Anzon options in upper
130's, mid Feb.-mid Mar.;
followed by third and fourth of
four options in low 140's, mid
Mar.-mid May; followed by one
exercised assignment option
well from Apache with Nexus in
high 70's, mid May-mid June;
followed by LOI for one
assignment well in low
200,000's, mid June-late July;
followed by four wells plus
option with NZOP in low 100's,
late July-late Dec. 2006.
Available; actively marketing.
Ocean Epoch six wells plus option mid 70's late April 2005 mid Dec. 2005 Available; actively marketing.
Ocean General six wells mid 70's mid June 2005 mid Jan. 2006 Note: 5th & 6th wells in mid
90's beginning early Nov. 2005
and ending mid Jan. 2006;
followed by one well plus two
option wells with Premier in
high 70's in Viet Nam beginning
mid Jan. 2006 and ending mid
Mar. 2006. Available; actively
marketing.
Ocean Baroness -- -- -- -- Shipyard/survey early June
until mid Aug. Mobe to GOM and
prep for one year plus option
with Amerada Hess in low 200's
beginning early Nov. 2005 and
ending early Nov. 2006.
Available; actively marketing.
Ocean Rover 950 day extension mid 170's late June 2005 mid Jan. 2008 Available; actively marketing.
</Table>
<Table>
<Caption>
RIG NAME WD DESIGN LOCATION STATUS* OPERATOR
BRAZIL
Ocean Yatzy 3,300' DP DYVI Super Yatzy Brazil Contracted Petrobras
Ocean Winner 3,500' Aker H-3 Brazil Contracted Petrobras
Ocean Alliance 5,000' Alliance Class Brazil Contracted Petrobras
INTERNATIONAL DRILLSHIPS (1)
Ocean Clipper 7,500' DP Fluor/Mitsubishi Brazil Contracted Petrobras
INTERNATIONAL JACKUPS (2)
Ocean Sovereign 250' Independent Leg Cantilever Indonesia Contracted Santos
Ocean Heritage 300' Independent Leg Cantilever Qatar Contracted Conoco/Phillips
UPGRADE (1)
Ocean Endeavor 2,000' Victory Class Shipyard Upgrading DODI
PURCHASE PENDING--RESERVED FOR UPGRADE (1)
Garden Banks** 2,200' Victory Class GOM Out of Service --
RIGS UNDER CONSTRUCTION (2)
Ocean Shield 350' Independent Leg Cantilever Shipyard -- --
Ocean Scepter 350' Independent Leg Cantilever Shipyard -- --
<Caption>
FUTURE CONTRACTS
RIG NAME CURRENT TERM DAYRATE (000S) START DATE EST. END DATE AND OTHER INFORMATION
BRAZIL
Ocean Yatzy 700 day extension mid 70's early Nov. 2003 early Oct. 2005 Four-year term extension with
Petrobras in mid 110's, plus
potential bonus, beginning
early Oct. 2005 and ending
early Oct. 2009. (21-day
maintenance Q3 or Q4).
Available; actively marketing.
Ocean Winner 700 day extension mid 50's early April 2004 mid Mar. 2006 Four-year term extension with
Petrobras in low 110's, plus
potential bonus, beginning mid
Mar. 2006 and ending mid Mar.
2010. Available; actively
marketing.
Ocean Alliance one year extension high 90's early Sept. 2004 early Sept. 2005 Four-year term extension with
Petrobras in mid 150's, plus
potential bonus, beginning
early Sept. 2005 and ending
early Sept. 2009. Available;
actively marketing.
INTERNATIONAL DRILLSHIPS (1)
Ocean Clipper 700 day extension low 100's early Jan. 2003 mid Dec. 2005 Five-year term extension with
Petrobras in low 180's, plus
potential bonus, beginning mid
Dec. 2005 and ending mid Dec.
2010. Available; actively
marketing.
INTERNATIONAL JACKUPS (2)
Ocean Sovereign eight wells upper 60's early May 2005 late Oct. 2005 Two wells with Amerada Hess
plus two exercised option wells
in mid 80's beginning late Oct.
and ending mid Dec. 2005;
followed by two option wells
with Santos in mid 70's
beginning mid Dec. 2005 and
ending mid Mar. 2006; followed
by three wells with Santos in
upper 60's beginning mid Mar.
and ending mid May; followed by
two wells with Anadarko in mid
80's beginning mid May and
ending early July 2006.
Available; actively marketing.
Ocean Heritage two wells plus option low 70's mid June 2005 late Mar. 2006 Available; actively marketing.
UPGRADE (1)
Ocean Endeavor -- -- -- -- Singapore shipyard for upgrade
to 10,000 ft. capable 5th
Generation rig. Estimated
completion early 2007; followed
by commissioning beginning
early Mar. 2007; followed by
LOI for a term of between two
and four years earning
approximate total revenue of
between $198 million and $355
million depending upon the
length of the contract selected
by the operator no later than
year-end 2005. Contract is
expected to begin mid 2007.
Available; actively marketing.
PURCHASE PENDING--RESERVED FOR UPGRADE (1)
Garden Banks** -- -- -- -- Currently retired from active
service as drilling and
production platform.
RIGS UNDER CONSTRUCTION (2)
Ocean Shield -- -- -- -- Singapore shipyard, estimated
completion Q1 2008. Available;
actively marketing.
Ocean Scepter -- -- -- -- Brownsville shipyard, estimated
completion Q1 2008. Available;
actively marketing.
</Table>
NOTES:
* GENERALLY, RIG UTILIZATION RATES APPROACH 95-98% DURING CONTRACTED PERIODS;
HOWEVER, UTILIZATION RATES CAN BE ADVERSELY IMPACTED BY ADDITIONAL DOWNTIME DUE
TO UNSCHEDULED REPAIRS AND MAINTENANCE, WEATHER CONDITIONS AND OTHER FACTORS.
** DIAMOND OFFSHORE SERVICES COMPANY HAS ENTERED INTO A DEFINITIVE AGREEMENT TO
PURCHASE THE GARDEN BANKS, SUBJECT TO CERTAIN CONDITIONS, WHICH IS EXPECTED TO
BE CONSUMMATED IN SEPTEMBER 2005. DIAMOND OFFSHORE DOES NOT CURRENTLY OWN THE
RIG.
GOM = Gulf of Mexico