⚡ A small California chipmaker has sued one of Japan's largest semiconductor companies over gallium nitride patents. The odd part is not the lawsuit. It is that the executive who filed it used to run the exact business he is now suing, and that the two companies had already taken each other to court less than three weeks earlier.

The countersuit filed in Texas

On August 10, 2026, Navitas Semiconductor announced that it had taken Renesas Electronics to court over patent infringement, filing in the Eastern District of Texas. The complaint accuses Renesas's SuperGaN power semiconductors and other major gallium nitride product lines of infringing four U.S. patents: Nos. 9,929,079, 11,545,838, 11,770,010 and 11,862,996.

Gallium nitride, usually shortened to GaN, is a semiconductor material that can switch electricity on and off far faster than silicon. Faster switching lets engineers shrink the coils and capacitors around a power converter and waste less energy as heat, which is why GaN showed up first in compact phone chargers and is now moving into the power supplies that feed racks of AI servers.

Navitas, founded in 2014, says it holds more than 300 patents issued or pending across GaN and silicon carbide. Its president and CEO, Chris Allexandre, framed the filing as a defense of that portfolio: "We respect valid intellectual property rights and we expect our competitors to do likewise."

Renesas told EE Times Japan on August 12 that it had no comment.

The plaintiff's CEO used to run the defendant's power business

Allexandre took over as Navitas president and CEO in September 2025. Before that he was senior vice president and general manager of Renesas's Power division. According to Navitas, he oversaw a power management and discrete products business worth roughly $2.5 billion, and earlier served as Renesas's chief sales and marketing officer.

Renesas moved first. On July 22, 2026, it brought its own case in the Northern District of California, alleging that Navitas poached employees to obtain trade secrets about next-generation GaN chips aimed at AI data centers. The complaint names Allexandre and former Renesas executive Felicia Cheng, and according to reporting on the filing, claims the two carried confidential presentations covering product specifications, technology roadmaps and market timing to their new employer. Renesas has also argued that the "Navitas 2.0" strategy the company announced after Allexandre arrived tracked its own confidential plans closely. Navitas uses that same label publicly to describe its pivot out of mobile and into high-power markets. In its quarterly filing with the SEC, Navitas said it was evaluating the complaint and intended to defend itself vigorously.

The two cases ask different questions. A trade secret claim is about whether someone walked out with information they had no right to take. A patent claim is about whether a product falls inside a patent somebody else owns. Neither answer settles the other, so both suits can run in parallel.

SuperGaN reached Renesas through an acquisition

SuperGaN came from Transphorm, a company spun out of the University of California, Santa Barbara in 2007 that Renesas bought for about $339 million, closing the deal on June 20, 2024.

At the time of that purchase, Allexandre was the Renesas executive responsible for power. He gave interviews explaining why the company wanted in-house GaN. Two years later he is asking a Texas court to find that the same product family infringes his current employer's patents.

Legally, that biography does not decide the question. Infringement turns on whether a product falls within valid patent claims, not on who filed first or where the technology came from.

The third company in the room

In July 2026, Wolfspeed brought its own patent case against Navitas in Delaware, asserting five patents including No. 8,169,005 against a broad sweep of Navitas products: the GaNFast, GaNSlim and GaNSafe families, plus GeneSiC MOSFETs and SiCPAK modules. Wolfspeed CEO Robert Feurle used a formulation Navitas would echo a month later: "We respect the IP rights of others, and we expect the same respect in return."

Wolfspeed is not a neutral bystander. It emerged from a prepackaged Chapter 11 restructuring in September 2025 in which Renesas, a major creditor, converted its debt into equity and convertible notes. After the U.S. Committee on Foreign Investment cleared the deal, Wolfspeed issued 16,852,372 shares to Renesas Electronics America on January 29, 2026, and Renesas took a board seat. In a securities filing made in May 2026, Renesas reported beneficial ownership of 39.9 percent of Wolfspeed, which is the ceiling written into their investor rights agreement. Its voting power is separately limited to 9.9 percent.

So the company suing Navitas in Delaware is roughly two-fifths owned, on that basis, by the company Navitas is suing in Texas. Allexandre pointed at that arrangement publicly on Navitas's July earnings call, describing the Wolfspeed action as part of a pattern of pressure. That is his reading. Neither company has said they coordinated, and no evidence of that has surfaced.

AI data centers changed what GaN is worth

The timing is not random. Yole Group's Power GaN 2025 report, published in October 2025, put the power GaN device market at $355 million in 2024 and projected roughly $3 billion by 2030, a compound annual growth rate of 42 percent. Data centers and telecom infrastructure are among the fastest-growing slices, forecast to pass $380 million by 2030 at a 53 percent annual rate.

What lit the fuse was NVIDIA's push toward 800-volt DC power distribution inside AI racks. As the power drawn by a single rack climbs, delivering it at 800 volts instead of a lower voltage cuts the current running through the copper, and less current means less heat and less metal. NVIDIA's architecture drew in Texas Instruments, Navitas, Infineon, Innoscience and onsemi as partners, with Yole expecting the first commercial rollouts around 2027.

Renesas is building toward the same window. In a company blog post from January 2026, it described preparing its fourth-generation-plus GaN products for automotive qualification (AEC-Q101) by mid-2027 and developing lower-voltage 40 to 200 volt GaN parts for the final conversion stages inside AI servers. The products Navitas named sit exactly where the growth is supposed to arrive.

Injunctions in GaN cases are not hypothetical

Infineon and Innoscience have been fighting over GaN patents in the United States, Germany and China since 2024, and the rulings have gone in both directions. In the US, the International Trade Commission found a violation of Section 337 on May 7, 2026 as to one of the two Infineon patents still at issue, and issued a limited exclusion order together with cease and desist orders, which took effect once the presidential review period closed on July 7. The two companies then described that same decision in opposite terms. Infineon called it proof of a GaN portfolio it puts at roughly 450 patent families; Innoscience said the ruling confirmed that its current products do not infringe and can still be imported and sold in the US.

In China the result ran the other way. In May 2026 the Suzhou Intermediate People's Court held that two Innoscience patents were being infringed by Infineon, and ordered it to stop selling and importing the products at issue, and in June the Supreme People's Court rejected Infineon's challenge to the injunctions. Innoscience called that a final victory. The trade publication ip fray reported that the Supreme People's Court treated the injunctions as interim relief, with the merits still to be decided.

Between them the two have collected exclusion orders and injunctions on two continents, several of them before the merits were settled. That is the realistic downside for whichever side loses a round in the Navitas cases.

What the size gap means

Navitas reported revenue of $10.5 million for the quarter ended June 30, 2026, up 22 percent from the previous quarter, with high-power markets growing more than 50 percent year over year. Its GAAP net loss was $228.2 million, but $203.1 million of that was a non-cash remeasurement of earnout liabilities, and the non-GAAP loss was $9.3 million. Cash stood at $557.4 million, more than double the level at the end of 2025.

Renesas reported non-GAAP revenue of 405.3 billion yen for the same quarter, at a non-GAAP operating margin of 32.7 percent. Converted at the August 14, 2026 rate of 159 yen to the dollar, that is about $2.5 billion, or roughly 240 times what Navitas booked in the same three months.

Navitas is now litigating in three federal districts at once, in eastern Texas, northern California and Delaware. All three complaints were filed within about five weeks of each other, and none has reached a ruling. The cash Navitas raised is what makes that survivable rather than fatal.

For Japan, the case lands on a sensitive spot. Renesas has positioned power as a pillar of growth since at least the Transphorm deal, and the GaN piece of that pillar was bought rather than built, from a California startup with operations that included a site in Aizu, Fukushima. Two of the executives who ran that business walked to a competitor, and the technology is now being contested in an American courtroom under American patent law. Japan's chip revival is usually discussed in terms of fabs and materials. Patents, and the people who understand them, decide a surprising amount of it too.

In Japan, the debate around this case keeps circling back to whether executives moving between rivals inevitably carry more than their own experience with them. When a senior engineer or executive joins a competitor where you live, where does the line fall between what is in their head and what belongs to the former employer?

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