Name of Corporations that Back the Teams

Well, first of all, click on the "Teams" link at the top of any page and you'll get most of the corporate sponsors:

Central League

Hanshin Tigers: Hanshin Railway - also has some department stores and real estate interests, I believe.

Chunichi Dragons: Chunichi Shimbun - newspaper

Yomiuri Giants: Yomiuri Group - newspaper and media (radio, TV) conglomerate

Yakult Swallows: Yakult - yogurt maker; Fuji Sankei Group, a media conglomerate, was the previous owner and still holds a large share of interest

Hiroshima Toyo Carp: Toyo Corporation - makes parts for cars; however the owner pretty much treats the team as a separate entity - a very interesting story for some researcher to pursue

Yokohama BayStars: Tokyo Broadcasting Service (TBS) - a media (TV/radio) conglomerate; recently sold from Maruha who makes various canned and processed fish products, renamed from (or a branch of?) Taiyo Corporation; when the parent company was renamed from Taiyo to Maruha, the team dropped the corporate sponsor in their name which made it easier to sell to TBS later

Pacific League

Fukuoka Daiei Hawks: Daiei Group - a department store chain which also own the Lawson chain of convienience stores

Seibu Lions: Seibu Group - a railway line joining Tokyo with Saitama; also has a large department store chain and even runs/sponsors some day care centers in the Kanto Plain

Osaka Kintetsu Buffaloes: Kintetsu Transporation - a railway line in the Osaka area, also runs trucks throughout Japan

Chiba Lotte Marines: Lotte - a gum and chocolate manufacturer; also has a chain of fast food restaurant called Lotteria; was partners with Burger King for a while, don't know if they still are or not

Hokkaido Nippon Ham Fighters: Nippon Ham Meats - makers of pork based products

Orix BlueWave: Orix Corporation - a leasing company with ties to Orico (Orient Corporation), a finance corporation; not sure if Orix or Orico is the parent, or if they're sister corporations

As you can see, only Yokohama has dropped the corporate name from the team name. Only Yokohama, Hiroshima, and the Giants are referred to in the standings by a name other than their corporate sponsor, i.e. today's standings:

Central League
1. Chunichi
2. Hanshin
3. Yokohama
4. Hiroshima
5. Kyojin ("Giants")
6. Yakult

Pacific League
1. Seibu
2. Daiei
3. Nippon Ham
4. Lotte
5. Kintetsu
6. Orix

The Giants get special treatment because they're the Giants. It's so hard to decide how to write team names because they're the exception to the rule. For example, saying "Yokohama vs. Chunichi" for yesterday's Game of the Week is natural. But "Hiroshima vs. Giants" just doesn't sound right, because one is using the location name for one and the mascot name for the other.

In the Pacific League one wouldn't say Fukuoka vs. Osaka, either, despite teams trying to identify more with their communities. And using the city name actually would work in the Pacific League since all of the teams are actually in different cities. (The Central League has both Yakult and the Giants in Tokyo.)

As for how the teams are used by their corporations, look around the site, this has been brought up a number of times.