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Acid Claims Not Infringed By Partly Neutralized Acid

Client Alert | 1 min read | 03.30.06

In Kao Corp., et al. v. Unilever United States, Inc., et al. (No. 05-1036, -1049; March 21, 2006), a Federal Circuit panel affirms a trial court's holding that Kao's patent is valid and enforceable but not infringed. The trial court interpreted Kao's claim to cover the acid forms of a copolymer and to exclude the salt forms of the copolymer. This claim construction was based, in part, on Kao's filing of another application directed to the salt form. The trial court took this filing as evidence that the patent in suit did not cover salt forms of the copolymer.

Unilever's accused infringing product included the claimed copolymer, but it was partially neutralized into the salt form. Unilever argued that it uses the salt form of the copolymer, and the Federal Circuit panel determines that Kao failed to rebut this assertion, other than offering an unsupported conclusion that Unilever uses a slightly neutralized acid and not a salt. Addressing Kao's argument that even if Unilever uses a salt it still infringes the claims, the panel distinguishes cases where an acid claim was infringed by a salt because in those cases the claims included the salt. Judge Newman dissents, pointing out that neutralizing 14.5% of the acid groups in the copolymer does not yield a salt and also that the record supports Kao's argument that Unilever uses a slightly neutralized acid.

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Client Alert | 3 min read | 09.15.25

Senate Finance Committee Looking to Take White River to the Train Station, Confirms DOJ Investigation into Tribal Tax Credits

On August 19, 2025, the U.S. Senate Committee on Finance (“Senate Finance Committee”) sent Paul Atkins, Chairman, U.S. Securities and Exchange Commission (“SEC”) a letter calling on the SEC to investigate White River Energy Corp (“White River”). In the letter, the Senate Finance Committee confirmed a criminal investigation into White River related to the sale of so-called “tribal tax credits” that according to both Congress and the IRS, do not exist. The letter further states that White River allegedly earned millions of dollars selling these credits and has not been forthcoming with investors regarding the existence of the criminal investigation. According to the Senate Finance Committee, White River has failed to file financial disclosure documents with the SEC since March 15, 2024, missing six consecutive reporting periods. The letter instructs White River to disclose the existence of the DOJ criminal tax investigation, and calls on the SEC to take action if White River fails to do so....