Press Releases 2026

SoftBank Corp. and Sierra Form Strategic
Partnership to Bring AI Agent-Powered
Customer Experiences to Japan

SoftBank to exclusively offer Sierra's conversational AI platform in Japan

July 14, 2026
SoftBank Corp.
Sierra

SoftBank Corp. ("SoftBank") and Sierra announced they formed a strategic partnership on July 13, 2026, to bring AI agent-powered customer experiences to the Japan market. Under the partnership, SoftBank will be Sierra's exclusive partner in Japan starting July 14, 2026.

Sierra's leading conversational AI platform enables organizations to improve the efficiency of their customer service operations by deploying AI agents. In addition to automatically generating optimal responses to customer inquiries, Sierra's agents also autonomously execute follow-up tasks, including processing product returns and completing various administrative procedures. SoftBank has already deployed Sierra to build customer support agents for its online-exclusive mobile brand, ‘LINEMO.’ Compared with the existing customer support service used by LINEMO, Sierra improved inquiry resolution rates from 83% to 97% and customer satisfaction scores from 74% to 93%. Accordingly, SoftBank plans to evaluate the deployment of Sierra for its ‘SoftBank’ and ‘Y!mobile’ mobile brands, as well as for other services provided by its group companies.

By offering Sierra's AI platform, SoftBank and Sierra aim to help Japan-based enterprises deploy and utilize AI agents for customer service operations to improve operational efficiency and service quality while enhancing the customer experience. To accelerate the rollout of Sierra in Japan, SoftBank will leverage its know-how and extensive enterprise customer network to partner exclusively with Sierra in the Japan market, offering Sierra's AI platform as a core service for AI-agent powered customer experiences. Sierra will leverage its technology and expertise as the leader in AI powered customer experiences to design, deploy, and optimize AI agents tailored to individual customer needs.

Junichi Miyakawa, President & CEO of SoftBank Corp., said: "We're delighted to form this strategic partnership with Sierra. AI agents are a transformative technology that will fundamentally reshape how companies engage with their customers. With Sierra's world-class AI agent technology, SoftBank will accelerate AI adoption among Japan's enterprises and help create customer experiences of higher value by enabling AI-native customer touchpoints."

Bret Taylor, Co-Founder and CEO of Sierra, said: "Japan has long set the global standard for how great companies serve their customers. The concept of ‘omotenashi’ — anticipating a customer's needs and serving them with genuine care — has influenced how we've built Sierra. Together with SoftBank, we're excited to help Japanese enterprises deliver that level of service at scale."

Features of Sierra's Conversational AI Platform

1. Goal-oriented AI agents that help customers achieve their goals

Goal-oriented AI Agents autonomously determine and carry out the most appropriate actions based on each situation. By understanding customers' inquiries and objectives, they provide optimal responses and complete the necessary tasks, delivering a seamless experience from initial inquiry through issue resolution.

2. AI agent development platform optimized for enterprise needs

Sierra enables enterprises to create better, more personalized customer experiences with AI agents tailored to their unique business needs by incorporating company-specific brand guidelines, business rules and knowledge. It also allows organizations to rapidly deploy AI agents across multiple functions, including customer support, sales and back-office operations.

3. Continuous AI improvement to enhance customer experience

By continuously improving AI agents based on customer conversations and inquiries across an integrated voice and text AI platform, Sierra enhances response quality and delivers higher levels of customer satisfaction.

About SoftBank Corp.

Guided by the SoftBank Group's corporate philosophy, "Information Revolution — Happiness for everyone," SoftBank Corp. (TOKYO: 9434) operates telecommunications and IT businesses in Japan and globally. Building on its strong business foundation, SoftBank Corp. is aiming to activate the potential of AI across its businesses and drive implementation in line with its "Activate AI for Society" growth strategy. While further growing its telecom business, SoftBank is expanding its AI computing infrastructure and AI and Cloud service businesses with the aim of becoming a provider of Next-generation Social Infrastructure. To learn more, please visit
https://www.softbank.jp/en/corp/

About Sierra

Sierra works with 40% of the Fortune 50, 1 in 3 of the world's leading banks, and major global telecommunications companies. It is the leading agentic customer experience platform — helping businesses build better, more human customer experiences with AI. With Sierra, the biggest brands in the world can deploy in weeks with immediate impact.
https://sierra.ai/

  • SoftBank, the SoftBank name and logo are registered trademarks or trademarks of SoftBank Group Corp. in Japan and other countries.
  • Other company, product and service names in this press release are registered trademarks or trademarks of the respective companies.