[Sik]

"T-119": publisher code (WTF no space?)
"1994.MAY": release date
"COMBAT CARS": you're reading another field there =P

[Donnyku]

That makes sense, thanks for clearing that up a bit.

[TmEE]

From an old doc describing MD ROM header and few more details :

CODE

10                  Takara
11                  Taito or Accolade
12                  Capcom
13                  Data East
14                  Namco or Tengen
15                  Sunsoft
16                  Bandai
17                  Dempa
18                  Technosoft
19                  Technosoft
20                  Asmik
22                  Micronet
23                  Vic Tokai
24                  American Sammy
25                  Nippon Computer Systems Corporation
29                  Kyugo
32                  Wolfteam
33                  Kaneko
35                  Toaplan
36                  Tecmo
40                  Toaplan
42                  UFL Company Limited
43                  Human
45                  Game Arts
47                  Sage's Creation
48                  Tengen
49                  Renovation or Telenet
50                  Eletronic Arts
56                  Razorsoft
58                  Mentrix
60                  Victor Musical Industries
69                  Arena
70                  Virgin
73                  Soft Vision
74                  Palsoft
76                  Koei
79                  U.S. Gold
81                  Acclaim/Flying Edge
83                  Gametek
86                  Absolute
93                  Sony
95                  Konami
97                  Tradewest
100                 T*HQ Software
101                 Tecmagik
112                 Designer Software
113                 Psygnosis
119                 Accolade
120                 Code Masters
125                 Interplay
130                 Activision
132                 Shiny & Playmates
144                 Atlus
151                 Infogrames
161                 Fox Interactive
239                 Disney Interactive

[Meat Miracle]

You can find a huge serial database here: http://www.katch.ne.jp/~kazutake/. Check under "Data room". I think this was collected from Sega of Japans release lists and other such "official" material, so it may not be completely accurate, compared to what numbers the games actually had.
You can also get all Saturn serials at satakore.com, these are more accurate since it collects data from the discs/covers.

It's interesting to note that (disregarding the Dreamcast) only the 32x and Saturn used an extra letter in the serials - GM-xxxx and GS-xxxx, obviously standing for Mars and Saturn.

Another thing to note: Megadrive numbering used G-4000 for normal games, and G-5000 for battery backed games (same for GM-4xxx and GM-5xxx for 32x normal and battery backed titles). But there was also a G-4500 line, also for battery backed titles. What made this line so special that it got its own numbering?

The Gamegear started at G-3100, not G-3000.... Why?

Naomi titles were GDS-0000 (sega) and GDL-0000 (third party).

[Scarred Sun]

Made a quick chart of 32X games with catalogue numbers here; from that, it looks like T-83 is GameTek and another vote on T-50 being EA.

[0r4ng3]

I've researched about these a little. The problem is it so needs more research.

Game Gear

All of the Game Gear Games have an extra 0 between the publisher characters and the game character. So for the early ones (until 1992 or something, like I said, I need to research this more) it's either the numbers that are here or with plus 0.

T-26 - (シグマ商事) Sigma Enterprises
T-28 - Genki
T-32 - Wolf Team > Namco Tales Studio
T-33 - Kaneko
T-44 - Sanritsu
T-49 - Telenet Japan, later used for Riot division
T-51 - Micro Cabin (T-51017, T-51027)
T-52 - System Soft (T-52017) - I have no clue if they merged later, but that's their configuration at this time.
T-54 - Face > ASCII (not sure about the merge, but the name is Face)
T-65 - Tsukuda Original (that's what's known for in english)
T-66 - Compile
T-143 - Hudson Soft
T-146 - Takara
T-149 - Infocom
T-154 - TECHNOS Japan

http://sega.jp/archive/segahard/gg/soft_licensee.html

Mega Drive

T-16 - Patlabor
T-17 - Dempa
T-18 - BMG Japan
T-20 - Asmik (before merge)
T-26 - Toho
T-29 - Kyugo
T-35 - Toaplan
T-41 - UNIPACC

Gigantic, I didn't finish it:
http://sega.jp/archive/segahard/md/soft_licensee.html

Mega CD

T-28 - Hot-B
T-64 - Data West
T-71 - Nichibutsu
T-74 - Pony Canyon
T-77 - Sur De Wave
T-92 - Polydor K.K. (was the Japanese division of Polydor, it was later absorbed by the Universal Music of Japan)
T-145 - Sony Music Entertainment

http://sega.jp/archive/segahard/mcd/soft_licensee.html

Saturn
T-178 is Hitachi
http://www.satakore.com/sega-saturn-game,,....-2.00-JPN.html

This post has been edited by 0r4ng3: 17 July 2010 - 04:24 PM

[Scarred Sun]

Third-Party T-Series Codes

[Sik]

What happened to all the codes before T-11? o_O I don't think Sega would start numbering at a number like 11, so I must be missing something here or there are effectively codes not in that list.

[Overlord]

It's entirely possible that the first 10 were reserved for some reason.

[doc eggfan]

There were two third party releases (Silver Cartride Series) for the Mark III, Master System, that predate the T-Series designation

Argos no Ju-Jiken (aka Rygar), Code = 001
Solomon no Kagi (aka Solomon's Key), Code = 002

Both were by Tecmo

So it is strange that Tecmo was assigned T-36. I was going to suggest that perhaps Tecmo were T-10, and Sega just started the T-Series at two digits, but that doesn't really work.

[Sik]

When was the first Tecmo Mega Drive game, though? They were probably assigned T-36 because they reached quite late. I know that Sega relied on small companies at first because Nintendo held a monopoly on all the big companies with their exclusivity contracts (today that would be called an indie heaven =P).

Also wait, what about the ROM serial numbers? SOJ and SOA/SOE used different methods to number their own programs. I feel too lazy to check the exact syntax (=P), but whatever, does anybody know if the company numbering also affects this field? Maybe T-01 to T-10 is Sega =|

[Scarred Sun]

Maybe T-01 to T-10 is Sega =|

That actually did cross my mind, given that there's roughly ten internal studios (though admittedly some like SST not making games) going around the time of the Mega Drive. I don't think there'd be any concrete way to prove that outside of internal docs, though.

[Andlabs]

Well just for the hell of it we went through a GoodGen set a few days ago with a small program I wrote to extract the copyright field out of ROMs and there doesn't seem to be anything we haven't documented in the wiki page now. If someone could provide me with ROM header layouts for other systems that have T-xx codes in the headers I could modify this to keep scanning other GoodSets.

This post has been edited by Andlabs: 19 July 2010 - 09:54 PM

[nineko]

Well, for Game Gear and Master System games there is Maxim's Header Reader. I checked a dozen of ROMs and I could confirm some of those T-codes such as T-11 for Taito and T-81 for Acclaim.

[Sik]

I just remembered, not all companies had T-xx codes - some used a four character abbreviature (Sega included). Maybe those would be assigned the T-01 to T-10 codes, but never decided to switch to the T-xx system? Which are the non-T-xx codes that have been used?