Pablo Zamora (plaintiff) and Clayborn Contracting Group, Inc. (Clayborn) (defendant) got into a dispute. Zamora claimed Clayborn owed him approximately $143,000 in damages. Clayborn sent Zamora an invoice, claiming Zamora owed Clayborn approximately $157,000. Zamora filed a complaint for his alleged damages, and Clayborn filed a cross-complaint. Zamora’s attorney sent an offer to settle the case under California Code of Civil Procedure § 998. The offer was for $149,999 and mistakenly reflected that judgment would be against Zamora instead of in favor of Zamora. Clayborn quickly accepted the offer. Zamora then filed a motion to set aside the § 998 offer because it was based on mistake, inadvertence, and excusable neglect. Zamora had only authorized a settlement for $149,999 to be paid by Clayborn to Zamora. However, the legal assistant who typed the offer made a typo in the offer document. Zamora had not previously offered to settle for less than $150,000 paid by Clayborn and had never offered to pay Clayborn any money. However, Clayborn said that it believed the offer was correct as written. The offer was consistent with the latest invoice sent to Zamora, and Clayborn’s attorney had not previously offered to give Zamora any money to settle. The trial court determined that the offer contained a ministerial or clerical error and granted the motion to set aside the judgment. Clayborn appealed, and the California Court of Appeal affirmed. Clayborn petitioned the California Supreme Court for review.