NERA Senior Managing Director Sarah Butler testified on behalf of e.l.f. Cosmetics in its successful defense against a trademark and trade dress infringement suit. Plaintiff Benefit Cosmetics claimed e.l.f.’s mascara product Lash ‘N Roll infringed the trademarks and trade dress of Benefit’s Roller Lash product, causing consumers to be confused. Ms. Butler, supported by Director Stephanie Child, provided survey evidence and testimony demonstrating there was no confusion and further establishing consumers were just as likely to associate other brands of mascara not alleged to infringe with Benefit’s product.  

The case came for trial before Judge Richard Seeborg of the US District Court of the Northern District of California. Judge Seeborg released his decision on 17 December 2024. In his decision, Judge Seeborg noted Ms. Butler’s survey “is the only empirical evidence provided as to consumer confusion” and further noted the critiques of Ms. Butler and Dr. Child’s research “ring hollow.” Ultimately, Judge Seeborg ruled that there was no risk of consumer confusion and that e.l.f. was not liable for trademark or trade dress infringement.