GGI (ジージーアイ) is one of those companies that played a genuine role in the video game industry during its golden age — without ever leaving a lasting mark on its memory.
Put that way, the claim might seem strange. Have you ever come across this name before? Probably not.
And yet, GGI appears repeatedly in sources from the era, often in the background, associated with activities as varied as they are difficult to pin down.
The company disappeared long ago, and the history of video games has granted it only a marginal place. It fell into oblivion.
It must be said that it never really sought the spotlight. As we shall see, some of its activities even strayed into particularly grey areas.
From the outset, one thing must be made clear: it is difficult to determine precisely where GGI's activities begin and end. On several occasions, we will see it appear as a central player, without its exact role being established with any certainty.
What is GGI?
To begin with, what does "GGI" stand for?
That is the first question… and already, answers are scarce. The meaning of "GG" remains unknown, but the letter "I" stands for International. An advertisement published in the magazine Game Machine (page 7) designates the company under the name GG International (G G インターナショナル). The phone number confirms that it is indeed the same company.
This detail matters: part of GGI's activities took place abroad.
Its headquarters were located in Tōkyō, in the Chiyoda ward — the exact address will prove useful later in tracking its trail.
The company was led by Takeo Oguri (小栗武夫). His name sometimes appears as 小栗武雄 in Game Machine, but this is most likely an error. Beyond his role as president, we have no reliable information about him.
But the real question lies elsewhere: what exactly did GGI do?
GGI seemed to have a hand in everything: hardware manufacturing, game modification, distribution both in Japan and abroad, and even licensing negotiations for productions developed by others. A remarkable versatility — one that was, on occasion, accompanied by decidedly more questionable practices.
The early days
At its founding, GGI… did nothing. Or to be more precise (page 2):
"The company, originally founded in 1973 as a dormant entity, was reactivated in November 1978 and entered the business of modifying TV games."
The fact that a company remained inactive for five years may seem strange. Without further information, it is difficult to draw any conclusion, except that GGI was probably not originally intended for the video game sector.
As for the "business of modifying TV games", this refers to what is known as the conversion kit industry. It was built on the idea of extending the lifespan of existing machines by modifying their content — either by adding electronic circuits or by replacing components such as ROMs. These modifications made it possible to offer "new" games without having to design a complete system from scratch, often drawing direct inspiration from successful titles. This model allowed manufacturers to quickly follow market trends, at a time (the late 1970s) when intellectual property questions remained murky. The games for which the most conversion kits were designed were breakout games, and later Space Invaders.
We discussed this at length in previous articles here and especially here.
And this is where a key element comes into play: an advertisement published in September 1978.
The first advertisement
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| https://onitama.tv/gamemachine/pdf/19780915p.pdf (page 5) |
This is an advertisement for the company Turtle (タートル), based in Amagasaki (尼崎). We have already encountered Turtle in a previous article. In 1976, it was a distributor (or a leasing company? I'm now less certain…) of Fuji Enterprise products. Fuji Enterprise was little more than a memory by 1978, and there was no longer any connection between the two companies.
At first glance, nothing unusual about this advertisement: Turtle is selling conversion kits for breakout games.
Among them is GG International — at the top of the list.
This is GGI's first known appearance.
Yet this position is surprising. The list consists almost exclusively of conventional distributors. And yet GGI, then completely unknown, appears in first place.
This raises an obvious question: is GGI really just a retailer?
Several elements give reason to doubt it:
- Game Machine would later describe GGI as a company specialising in game modification (page 2)
- Turtle, for its part, had no technical capabilities of its own. Here is how Turtle presented itself at AM Show '78 (page 8):
"Our company is primarily a leasing business, not a manufacturer."
This is not a certainty, but the clues converge.
If so, this advertisement would simply document… GGI's earliest products.
Let us now turn to these conversion kits. Here is what the advertisement says:
"Just add a PCB to enrich your game content! 4-digit display PCB / UFO PCBs Now on sale!!
- Can be easily installed by anyone — even a layperson — on either table-type or arcade-type "Scratch" or "Break" TV block-breaking game machines (excluding microcomputer-based models). - Transform your machine into something new!! Sales will increase dramatically. (Proven at our own location) - With the "UFO PCBs", combinations allow for up to 24 different game variations.
4-Digit Display
・Combined with the UFO board, it becomes a groundbreaking block game.
UFO No.1
・When the ball hits a block in the yellow row (4th row from the top), it returns to normal movement. ・You can also choose to keep the UFO movement going continuously.
UFO No.2
・The UFO ball returns to normal movement when it hits a block in the yellow row (4th row from the top).
Pro & Amateur Combined
・The ball moves randomly like a UFO.
Super UFO
・Combined with the 4-digit board, the fun reaches its peak.
If you send us your board, we will install it for you at our company (installation fees are charged separately). Beware of inferior imitation products."
The conversion kits
The advertisement highlights several features:
- addition of a 4-digit display
- "UFO" ball behaviour (unusual movement patterns)
- gameplay variations of up to 24 combinations
That last point is probably more of a marketing argument than a measurable reality. Otherwise, congratulations if you managed to find all 24 combinations!
The kits presented here only work on machines using TTL (Transistor-Transistor Logic) technology — that is, electronic circuits without a microprocessor, where the game's behaviour depends directly on physical wiring. Unlike more recent systems, this isn't about replacing a ROM: the modification here requires hardware-level intervention, sometimes quite complex. The advertisement nevertheless insists on the simplicity of installation — a classic marketing argument.
We saw that Game Machine states GGI was reactivated in November 1978. However, the first advertisement mentioning GGI dates from September 1978. We can even go further back, since Turtle had begun advertising its conversion kits as early as June 1978.
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| https://onitama.tv/gamemachine/pdf/19780615p.pdf (page 14) |
GGI may therefore have been reactivated as early as the first half of 1978.
Broader activities?
Another element is intriguing. An advertisement published shortly afterwards by the company Hōwa Tokki (宝和特機) presents very similar products: the same "4-digit display" PCB, the same UFO variants, and nearly identical visuals.
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| https://onitama.tv/gamemachine/pdf/19781001p.pdf (page 5) |
Two possibilities:
- simple reuse of visuals by the magazine
- or distribution of GGI's products through multiple intermediaries
In the second case, GGI would not be limited to a local network, but would already be operating on a larger scale. This hypothesis is reinforced by a later mention in Game Machine, indicating that the company was carrying out modification activities "on a large scale".
UFO, a popular variant?
You have probably noticed how proud Turtle is of its UFO variants. It is far from the only company to promote breakout games where the ball follows unusual trajectories. By the end of 1978, Game Machine is full of advertisements touting the UFO variant. I wanted to test a period-accurate breakout game with a UFO mode using the MAME emulator — I could not find a single one. It is interesting to note that today everyone knows what a breakout game is, but nobody remembers the UFO gameplay mode.
1979 ?
Ultimately, we can see that GGI was a pioneering company in the conversion industry. As for 1979, no source I am aware of documents it directly, but we know that GGI continued along the same business model. Where to look, then? Simple enough: Turtle kept selling conversion kits. That is the trail to follow.
At the beginning of 1979, Turtle announced (page 7) it was discontinuing the UFO variant and launching a new one called Space Block. As the name suggests, this variant appears to have been inspired by Space Invaders, which was taking the world by storm at the time. Here, the blocks move from top to bottom, just like the enemies in Space Invaders.
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| Space Block |
Taito released Space Invaders Part II in mid-1979. Conversion kit manufacturers wasted no time for "finding inspiration". For example :
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| https://onitama.tv/gamemachine/pdf/19790115p.pdf (page 7) |
Here, Turtle offered kits to:
- convert a breakout game into an Invader game — i.e. a Space Invaders clone
- convert an Invader game into an Invader Part II-style game — i.e. adding features specific to Space Invaders Part II, such as colour, different enemy behaviours, and so on
- convert an Invader game into yet another different type of game
- replace the dial controller with a joystick
The mention of "supplied with a P-ROM for service (maintenance)" (サービス用P-ROM付) shows that these kits were targeting microprocessor-based systems, marking a clear break from the earlier TTL hardware conversions. The use of such a ROM implies a direct modification of the program, making it possible to adapt machines from a wide variety of manufacturers. Similarly, the phrase "complete repair kit for Invaders from all manufacturers" suggests a technical service capable of working on a highly heterogeneous range of machines. This is far from a handful of hobbyists: everything points to an organised operation with advanced technical expertise.
Other companies offered similar services — relying on comparable technologies and providing similar features — such as Hōwa Tokki or Naka Nihon Lease (中日本リース), based in Nagoya.
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| https://onitama.tv/gamemachine/pdf/19790715p.pdf (page 16) |
One can therefore imagine that GGI gradually built up a network of commercial companies acting as intermediaries with customers. That said, caution is warranted: there is no proof that GGI collaborated with any company other than Turtle. All we have are striking similarities between the services offered by Turtle and those offered by these other companies — and perhaps others still, since not every company active in this field necessarily advertised in Game Machine.
The first "original" game?
Still in the same vein, at the beginning of 1980 (page 10), Turtle offered what is today a legendary game: Spacian (スペーシアン).
It is a port of Galaxian (Namco) running on Space Invaders hardware — made possible, of course, by a conversion kit.
During a 2019 interview, Spacian was presented to Tomohiro Nishikado, the creator of Space Invaders, for the first time. He was very impressed, even if the game did run rather slowly…
Bankruptcy after two years
In June 1980 (page 2), Game Machine announced:
"GGI (Chiyoda, Tōkyō, president Takeo Oguri (小栗武雄)) issued a dishonoured check at Daiichi Mutual Bank on March 22nd and had its banking transactions suspended."
In other words, GGI went bankrupt.
The article also noted:
- large-scale game modification activities
- a debt of approximately 100 million yen
The contrast is striking.
In the space of barely two years, GGI went from:
- an emerging player in the conversion industry
- to a company operating on a large scale
- then to sudden bankruptcy
Should we see in this poor management? A particular incident? Nothing allows us to say.
But placed in context, this collapse was not an isolated one. Turtle's last advertisement dates from April 1980. Hōwa Tokki and Naka Nihon Lease had already disappeared.
The conversion industry itself was collapsing at the same period. It had depended largely on operators' need to convert their Invader machines. With the release of Galaxian, built on newer and more powerful hardware, an entire ecosystem vanished.
GGI did not escape this wave.
Conclusion
Is this already the end for GGI? Not at all — it is only the beginning.
Despite this swift bankruptcy, the company did not disappear entirely from the radar. On the contrary, it would resurface in unexpected contexts, sometimes far from Japan, and often in situations that were murky at best.
The story of GGI is, in reality, only just beginning.
