I'll research this company before writing the profile.
Let me verify the MediaTek case context and Sanyo's product lines.
Sanyo North America, Inc. (Sanyo North America Corporation)
Company overview. Sanyo North America Corporation is the U.S. subsidiary of Sanyo Electric Co., Ltd., the Japanese electronics manufacturer founded by Toshio Iue in 1947 and headquartered in Moriguchi, Osaka. The U.S. entity was established March 22, 1961, as a Delaware corporation with headquarters at 2055 Sanyo Avenue, San Diego, California, and is 100% owned by Sanyo Electric (Panasonic Corporation disclosure, Dec. 2009). Panasonic acquired a majority stake in Sanyo in December 2009 (~¥403.8 billion / ~$4.6 billion) and made Sanyo a consolidated subsidiary, later fully absorbing it. As of Sept. 30, 2009, Sanyo North America reported paid-in capital of ~$402 million and net sales of ~$479 million for fiscal year ended March 2009 (down from ~$1.19 billion the prior year). Employee counts are not consistently published for the subsidiary.
Products / operations. The U.S. entity served as Sanyo's regional sales and marketing center for North America, distributing Sanyo products rather than being a primary manufacturer. Parent Sanyo made rechargeable batteries (nickel-cadmium, NiMH, lithium-ion), HIT solar cells and modules, semiconductors, capacitors, optical pickups, commercial air conditioning and refrigeration equipment, and consumer electronics including digital cameras, projectors, and televisions. Sanyo was the world's largest rechargeable-battery producer before the Panasonic acquisition; it sold its semiconductor operations to ON Semiconductor in 2010 and its mobile-phone unit to Kyocera in 2008.
Patent-litigation posture. Sanyo North America appears once in the tracked data, as a defendant (0 plaintiff cases). That profile is consistent with an operating company defending an infringement suit, not a patent assertion entity. In the underlying dispute, Sanyo was itself also an active patent enforcer: it filed a parallel multi-patent case against MediaTek in the Central District of California (Sanyo Electric Co. v. MediaTek, 2:06-cv-01225).
Notable case. MediaTek, Inc. v. Sanyo Electric Co., Ltd. et al., No. 6:05-cv-323-LED (E.D. Tex., Tyler Division), filed Aug. 31, 2005. MediaTek asserted three patents (U.S. 5,867,819; 6,118,486; 5,751,356) covering audio decoding and MPEG video/audio coding against Sanyo's audio decoders and integrated circuits in DVD recorders, DVD players, digital TVs, set-top boxes, and mobile devices. The case was litigated through Markman proceedings in 2007 and settled on the eve of trial, resolving both the Texas and California actions.