.
.
.
EXHIBIT 99.1
DIAMOND OFFSHORE DRILLING, INC. RIG STATUS REPORT AS OF SEPTEMBER 27, 2004
<Table>
<Caption>
DAYRATE
RIG NAME WD DESIGN LOCATION STATUS* OPERATOR CURRENT TERM (000S)
DOMESTIC DEEPWATER SEMISUBMERSIBLES (6)
Ocean Quest 3,500' Victory Class GOM Contracted Noble Energy one well plus option low 50's
Ocean Star 5,500' Victory Class GOM Contracted/Repairs Kerr-McGee fourth of four wells low 60's
Ocean America 5,500' Ocean Odyssey GOM Contracted/Repairs Mariner third of three wells mid 70's
plus option
Ocean Valiant 5,500' Ocean Odyssey GOM Contracted ENI second of three wells high 50's
plus option
Ocean Victory 5,500' Victory Class GOM Contracted W&T Offshore two wells mid 40's
Ocean Confidence 7,500' DP Aker H-3.2
Modified GOM Contracted BP five-year term 170's
DOMESTIC 2ND/3RD GENERATION SEMISUBMERSIBLES (3)
Ocean Concord 2,200' F&G SS-2000 GOM Idle DODI -- --
Ocean Lexington 2,200' F&G SS-2000 GOM Contracted Walter Oil & Gas one well plus option high 40's
Ocean Saratoga 2,200' F&G SS-2000 GOM Contracted LLOG one well extension plus mid 40s
option
</Table>
<Table>
<Caption>
RIG NAME START DATE EST. END DATE FUTURE CONTRACT AND OTHER INFORMATION
DOMESTIC DEEPWATER SEMISUBMERSIBLES (6)
Ocean Quest early Sept. 2004 mid Nov. 2004 LOI for one well plus option in mid 70's beginning
mid Nov. and ending early Dec. 2004, subject to
Noble Energy option. Available; actively marketing.
Ocean Star early June 2004 early Oct. 2004 Estimated 10-21 day repair due to Ivan; 220 day
extension with Kerr-McGee in upper 70's beginning
early Oct. 2004 and ending mid May 2005. Available;
actively marketing.
Ocean America mid June 2004 late Oct. 2004 Estimated 10-21 day repair due to Ivan; One well
extension plus option with Mariner in mid 80's
beginning late Oct. 2004 and ending mid Jan. 2005.
Available; actively marketing.
Ocean Valiant late Dec. 2003 mid Oct. 2004 One well plus options with Kerr-McGee in mid
80's beginning mid Oct. and ending mid Dec.
2004. Available; actively marketing.
Ocean Victory mid Aug. 2004 late Dec. 2004 Rate adjusts to mid 70's in late Sept. LOI
for one well plus option in mid 90's
beginnning late Dec. 2004 and ending early
March 2005. Available; actively marketing.
Ocean Confidence early Jan. 2001 early Jan. 2006 Available; actively marketing.
DOMESTIC 2ND/3RD GENERATION SEMISUBMERSIBLES (3)
Ocean Concord -- -- Approximately 120 days maintenance beginning
early June and ending early Oct. 2004. One
well plus options with Kerr-McGee in mid
50's beginning early Oct. and ending late
Nov. 2004. LOI for one well in mid 50's
beginning late Nov. 2004 and ending late
Jan. 2005. Available; actively marketing.
Ocean Lexington late March 2004 mid March 2005 One well extension plus option with Walter
in high 30's beginning mid Aug. and ending
early Sept. 2004; followed by three well
extension with Walter beginning in early
Sept. and ending in mid Dec. 2004. Rate for
first well in mid 40's, second and third
wells in upper 40's. Three additional
extension wells with Walter beginning in mid
Dec. 2004 and ending late March 2005. Rate
for first and second wells in mid 50s with
third well in low 60s. Available; actively
marketing.
Ocean Saratoga late June 2004 late Sept. 2004 One additional well plus option with LLOG in
low 50s beginning late Sept. and ending late
Oct. 2004. Available; actively marketing.
</Table>
DIAMOND OFFSHORE DRILLING, INC. RIG STATUS REPORT AS OF SEPTEMBER 27, 2004
<Table>
<Caption>
DAYRATE
RIG NAME WD DESIGN LOCATION STATUS* OPERATOR CURRENT TERM (000S)
DOMESTIC JACKUPS (12)
Ocean Crusader 200' Mat Cantilever GOM Contracted Walter Oil & Gas two wells plus option mid 30's
Ocean Drake 200' Mat Cantilever GOM Contracted/DODI Chevron/Texaco two wells plus option mid 30's
Ocean Champion 250' Mat Slot GOM Contracted Millennium one well plus option mid 30's
Ocean Columbia 250' Independent Leg
Cantilever GOM Contracted ADTI/Kerr-McGee one well plus option mid 30's
Ocean Spartan 300' Independent Leg
Cantilever GOM Contracted LLOG two wells plus option high 30's
Ocean Spur 300' Independent Leg
Cantilever GOM Contracted Mariner two wells high 30's
Ocean King 300' Independent Leg Houston
Cantilever GOM Contracted Exploration two wells mid 40s
Ocean Nugget 300' Independent Leg
Cantilever GOM Contracted Spinnaker one well mid 30's
Ocean Summit 300' Independent Leg
Cantilever GOM Contracted LLOG three wells plus option high 30's
Ocean Warwick 300' Independent Leg
Cantilever GOM Contracted/DODI Newfield -- --
Ocean Titan 350' Independent Leg
Cantilever GOM Contracted Stone Energy second of two wells mid 40's
plus option
Ocean Tower 350' Independent Leg
Cantilever GOM Contracted EOG Resources second of two wells high 30's
</Table>
<Table>
<Caption>
RIG NAME START DATE EST. END DATE FUTURE CONTRACT AND OTHER INFORMATION
DOMESTIC JACKUPS (12)
Ocean Crusader mid Sept. 2004 early Nov. 2004 Available; actively marketing.
Ocean Drake late Aug. 2004 late Oct. 2004 Working with operator to stabilize drill
site following Ivan. Available; actively
marketing.
Ocean Champion early Sept. 2004 late Oct. 2004 Available; actively marketing.
Ocean Columbia early Sept. 2004 mid Oct. 2004 Available; actively marketing.
Ocean Spartan early Sept. 2004 late Nov. 2004 Available; actively marketing.
Ocean Spur early Sept. 2004 late Oct. 2004 Available; actively marketing.
Ocean King late Aug. 2004 early Dec. 2004 Available; actively marketing.
Ocean Nugget mid Sept. 2004 mid Oct. 2004 Available; actively marketing.
Ocean Summit early Sept. 2004 mid Dec. 2004 Available; actively marketing.
Ocean Warwick -- -- Evaluating damage from Ivan.
Ocean Titan mid July 2004 early Oct. 2004 One well plus option with Stone in low 50's
beginning in early Oct. and ending early
Nov. 2004. Available; actively marketing.
Ocean Tower mid July 2004 early Oct. 2004 Available; actively marketing.
</Table>
DIAMOND OFFSHORE DRILLING, INC. RIG STATUS REPORT AS OF SEPTEMBER 27, 2004
<Table>
<Caption>
DAYRATE
RIG NAME WD DESIGN LOCATION STATUS* OPERATOR CURRENT TERM (000S)
INTERNATIONAL SEMISUBMERSIBLES (17)
MEXICO
Ocean Ambassador 1,100' Bethlehem SS-2000 GOM Contracted PEMEX four year term work mid 50's
Ocean Whittington 1,500' Aker H-3 GOM Contracted PEMEX four year term work low 60's
Ocean Worker 3,500' F&G 9500 Enhanced
Pacesetter GOM Contracted PEMEX four year term work high 60's
Ocean Yorktown 2,850' F&G SS-2000 GOM Contracted PEMEX four year term work mid 40's
AFRICA
Ocean Nomad 1,200' Aker H-3 Gabon Contracted Vaalco/SASOL three wells plus option high 40's
NORTH SEA
Ocean Guardian 1,500' Earl & Wright Sedco
711 Series North Sea Contracted Shell one year high 40's
Ocean Princess 1,500' Aker H-3 North Sea Contracted Talisman three wells plus option low 50's
Ocean Vanguard 1,500' Bingo 3000 North Sea Contracted Talisman one well low 60's
AUSTRALASIA
Ocean Bounty 1,500' Victory Class Australia Contracted OMV three wells mid 70's
Ocean Patriot 1,500' Bingo 3000 New Zealand Contracted Tap Oil one well high 70's
Ocean Epoch 1,640' Korkut Australia Contracted Santos Exeter/Mutineer mid 60's
development plus option
Ocean General 1,640' Korkut Vietnam Contracted PVE&P five completion options mid 50's
Ocean Baroness 7,000' Victory Class Indonesia Contracted Unocal 180 day option 110's
Ocean Rover 7,000' Victory Class Malaysia Contracted Murphy one well low 120's
</Table>
<Table>
<Caption>
RIG NAME START DATE EST. END DATE FUTURE CONTRACT AND OTHER INFORMATION
INTERNATIONAL SEMISUBMERSIBLES (17)
MEXICO
Ocean Ambassador late July 2003 mid Dec. 2007 Available.
Ocean Whittington late July 2003 early Oct. 2006 Available.
Ocean Worker mid Aug. 2003 late July 2007 Available.
Ocean Yorktown late Oct. 2003 mid July 2007 Available.
AFRICA
Ocean Nomad early May 2004 late Sept. 2004 LOI for one year program in U.K. North Sea
in low 80's beginning late Jan. 2005 and
ending late Jan. 2006. Available; actively
marketing.
NORTH SEA
Ocean Guardian late March 2004 late March 2005 LOI for one year program in U.K. North Sea
in low 80's beginning late Mar. 2005 and
ending late Mar. 2006. Available; actively
marketing.
Ocean Princess early Aug. 2004 mid Oct. 2004 One well extension in low 60's beginning mid
Oct. and ending late Dec. 2004, followed by
one year extension in low 80's beginning
late Dec. 2004 and ending late Dec. 2005.
Available; actively marketing.
Ocean Vanguard late June 2004 early Oct. 2004 One well in Norway with ENI in low 140's
beginning early Oct. 2004 and ending early
Jan. 2005. Available; actively marketing.
AUSTRALASIA
Ocean Bounty early Sept. 2004 late Dec. 2004 LOI for one well plus option in mid 70's
beginning late Dec. 2004 and ending late
Jan. 2005, followed by LOI for one well plus
option in high 70's beginning in late Jan.
2005 and ending mid Feb. 2005. Available;
actively marketing.
Ocean Patriot early Sept. 2004 mid Sept. 2004 Mobe to Australia beginning mid Sept. and
ending late Sept. 2004. First of two wells
with Bass Straits O&G beginning late Sept.
and ending early Oct. Two wells with Santos
beginning early Oct. and ending late Oct.
LOI for two wells plus option beginning late
Oct. and ending mid Dec. Second of two wells
with Bass Straits beginning mid Dec. 2004
and ending mid Jan. 2005. LOI for two wells
beginning mid Jan. and ending mid Feb. Two
wells plus option with Santos beginning mid
Feb. and ending late April. LOI for four
wells beginning late April and ending late
July 2005. All wells in high 70's.
Available; actively marketing.
Ocean Epoch mid Jan. 2004 late Feb. 2005 Available; actively marketing.
Ocean General mid June 2004 late Oct. 2004 LOI for two wells in Korea plus mobe/demobe
in high 60's beginning late Oct. and ending
mid Feb. 2005. Available; actively
marketing.
Ocean Baroness late April 2004 early Nov. 2004 Available; actively marketing.
Ocean Rover early Sept. 2004 early Oct. 2004 LOI for one assignment well in low 100's
beginning early Oct. and ending early Nov.,
followed by LOI for second assignment well
in lower 110's beginning early Nov. and
ending late Dec. 2004. Fourth option well
with Murphy declared in low 120's beginning
late Dec. 2004 and ending mid Jan. 2005.
Available; actively marketing.
</Table>
DIAMOND OFFSHORE DRILLING, INC. RIG STATUS REPORT AS OF SEPTEMBER 27, 2004
<Table>
<Caption>
DAYRATE
RIG NAME WD DESIGN LOCATION STATUS* OPERATOR CURRENT TERM (000S)
BRAZIL
Ocean Yatzy 3,300' DP DYVI Super Yatzy Brazil Contracted Petrobras 700 day extension mid 70's
Ocean Winner 3,500' Aker H-3 Brazil Contracted Petrobras 700 day extension mid 50's
Ocean Alliance 5,000' Alliance Class Brazil Contracted Petrobras four-year contract low 110's
INTERNATIONAL DRILLSHIPS (1)
Ocean Clipper 7,500' DP Fluor/Mitsubishi Brazil Contracted Petrobras 700 day extension low 100's
INTERNATIONAL JACKUPS (2)
Ocean Sovereign 250' Independent Leg
Cantilever Indonesia Contracted Premier one well plus option low 60's
Ocean Heritage 300' Independent Leg
Cantilever -- Dry tow to India DODI -- --
COLD STACKED (4)
Ocean Liberator 600' Aker H-3 S. Africa Cold Stacked DODI -- --
Ocean Endeavor 2,000' Victory Class GOM Cold Stacked DODI -- --
Ocean Voyager 3,200' Victory Class GOM Cold Stacked DODI -- --
Ocean New Era 1,500' Korkut GOM Cold Stacked DODI -- --
</Table>
<Table>
<Caption>
RIG NAME START DATE EST. END DATE FUTURE CONTRACT AND OTHER INFORMATION
BRAZIL
Ocean Yatzy early Nov. 2003 mid Oct. 2005 Available.
Ocean Winner early April 2004 mid March 2006 Available.
Ocean Alliance early Sept. 2000 mid Oct. 2004 Available.
INTERNATIONAL DRILLSHIPS (1)
Ocean Clipper early Jan. 2003 early March 2006 Available; actively marketing.
INTERNATIONAL JACKUPS (2)
Ocean Sovereign early Sept. 2004 mid Oct. 2004 LOI for two wells plus option in low 60's in
Bangladesh beginning late Oct. 2004 and
ending late April 2005. Includes
mobe/demobe. Available; actively marketing.
Ocean Heritage -- -- Lump sum mobe to India beginning early Sept.
and ending mid Oct. Six wells plus four to
seven options with Cairn Energy in lower
60's beginning mid Oct. 2004 and ending
early May 2005. Available; actively
marketing.
COLD STACKED (4)
Ocean Liberator -- -- Cold stacked Nov. '02.
Ocean Endeavor -- -- Cold stacked March '02.
Ocean Voyager -- -- Cold stacked March '02.
Ocean New Era -- -- Cold stacked Dec. '02.
</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.
GOM = Gulf of Mexico