When Arbitration Emails Go Unread: Lessons From The Ninth Circuit

On August 5, 2026, the U.S. Court of Appeals for the Ninth Circuit recently issued a decision in Rickes v. Thermo Fisher Scientific, Inc., that should prompt retailers and e-commerce merchants to carefully review how they obtain agreement to arbitration provisions and class action waivers. Although the order is unpublished, and involved an employment dispute, the court’s general reasoning will be cited as persuasive authority and carries significant implications for any company that relies on email-based notices to bind individuals to dispute resolution terms. 

The Ninth Circuit’s Decision

Scott Rickes, a former Thermo Fisher manager, brought a putative class action alleging age discrimination and related California claims after his employment ended. Thermo Fisher sought to compel arbitration of his individual claims and dismiss the class claims based on a Mutual Dispute Resolution Agreement (MDRA) distributed to employees by email in 2019. The MDRA said employees would be deemed to agree if they did not opt out within 45 days after being told the agreement was available for review.

In seeking to enforce the terms of its contract, Thermo Fisher showed it sent four MDRA-related emails to Rickes’ work address. However, Thermo Fisher’s records did not show that he viewed the emails, clicked the MDRA hyperlink, or otherwise interacted with the arbitration materials. And Rickes declared that he received a high volume of work emails, did not recall any MDRA communication, and that he had never seen the agreement before the litigation.

The Ninth Circuit held that Thermo Fisher had not proved Rickes assented to the MDRA. Under California law, contract formation requires notice and mutual assent. As the court explained, “silence alone does not constitute assent,” and continued employment after failure to opt out was “not enough to establish mutual assent.” In electronic transactions, assent may be inferred from affirmative conduct—such as “clicking buttons,” “checking boxes,” or otherwise interacting with contractual terms. The court contrasted this record with cases involving objective evidence of assent, including a signed acknowledgment, undisputed receipt and review of the agreement, or prior acceptance of arbitration as a condition of employment. Because Thermo Fisher’s records showed only email delivery instead of actual viewing of the messages, clicking the hyperlink, or otherwise engaging with the MDRA, the court affirmed denial of the motion to compel.

Why It Matters

Retailers often seek to enforce arbitration clauses and class action waivers in consumer disputes, including putative class actions. These provisions commonly appear in terms of service, loyalty programs, subscriptions, mobile apps, and online checkout processes. The Rickes decision therefore provides helpful evidentiary guidance: retailers should strive to maintain thorough records demonstrating both notice and an affirmative manifestation of assent if they intend to compel arbitration or enforce a class waiver. Notably, however, Rickes was decided in the employment context, where courts are often more exacting on issues of arbitration assent than they are in consumer transactions.

While that distinction is important to keep in mind, the Rickes decision nevertheless serves as a cautionary tale. Delivery alone, or a consumer’s failure to opt out, may not be sufficient to establish assent. Retailers should preserve evidence of the terms presented, the consumer’s interaction with those terms, and any records reflecting the consumer’s assent.

Practical Steps for Retailers

• Make review simple. Present the arbitration and class-waiver language clearly and provide the full terms before acceptance.
• Require affirmative assent of an arbitration agreement. Use a conspicuous checkbox, such as an “I Agree” button, or electronic signature tied to the arbitration terms.
• Preserve and audit the record. Retain the terms shown, linked disclosures, and logs of the consumer’s affirmative assent. Review the process routinely to ensure it is up to date and comprehensive.
• Follow up with nonresponders. Track recipients who do not open or acknowledge the terms. Consider neutral follow-ups through paper delivery or electronic outreach.