Sanyo Electric Co., Ltd. (三洋電機株式会社) — commonly "Sanyo" — was a Japanese electronics manufacturer founded in 1947 by Toshio Iue as Sanyo Electric Works and incorporated in 1950, headquartered in Moriguchi, Osaka. It was publicly listed on the Tokyo Stock Exchange (ticker 6764, from 1954) and on NASDAQ (SANYY). Per Wikipedia, consolidated revenue for the fiscal year ended March 2007 was roughly ¥2.2 trillion, with about 99,875 consolidated employees as of March 2008. Sanyo ceased to exist as an independent company: Panasonic acquired a 50.2% stake in December 2009, made it a wholly owned subsidiary in April 2011, and Sanyo was delisted from the TSE on March 29, 2011. The SANYO brand was phased out from April 2012; the legal entity reportedly still exists but is effectively dormant, with staff transferred into Panasonic.
Products / operations. Sanyo was a diversified operating company. Its best-known lines were rechargeable batteries (nickel-cadmium from 1964, NiMH from 1990, lithium-ion from 1994, and the Eneloop low-self-discharge NiMH line), solar cells (the HIT heterojunction crystalline-silicon cell), semiconductors, home appliances (washing machines, refrigerators, air conditioners), televisions, projectors, digital cameras, mobile phones, and automotive/HV battery supply to customers including Honda, Ford, Volkswagen and PSA. Businesses were divested over time: mobile phones to Kyocera (2008), semiconductors to ON Semiconductor (completed 2011), and Japanese/SE-Asian refrigerator and washing-machine operations to Haier (2011).
Litigation posture. Sanyo is an operating company, not an NPE. The tracked data show 3 cases as plaintiff and 1 as defendant — consistent with an active two-way litigant asserting its own chipset patents while being counter-sued. It is not a patent-assertion vehicle and has no NPE-style characteristics.
Notable cases. The tracked matters are all part of the Sanyo–MediaTek dispute over optical-disc and audio/video decoding chipset technology. Sanyo sued MediaTek in the Central District of California (including C.D. Cal. No. 2:06-cv-01225), asserting patents such as U.S. 5,818,801 on CD-ROM decoding, while MediaTek countersued in the Eastern District of Texas, Tyler Division (No. 6:05-cv-323), asserting three patents (e.g., U.S. 5,867,819, 6,118,486, 5,751,356) against Sanyo Electric and Sanyo North America Corporation (San Diego). The parties settled both suits on the eve of trial. The E.D. Texas filing reflects that plaintiff-friendly venue's use in the mid-2000s, not NPE activity.