Panasonic said it is purchasing an additional 80% stake in the Arizona-based company that it didn’t already own.

Panasonic took a 20% stake in Blue Yonder in July, deepening the companies’ relationship as they jointly develop digital technology for managing logistics, retail and manufacturing operations.

Panasonic’s imaging technology, for example, can be used to monitor inventory levels on store shelves, sending data back to Blue Yonder’s supply-chain software, triggering restocking.

Blue Yonder helps retailers, manufacturers and logistics providers to predict customer demand and serves more than 3,000 customers.

Blue Yonder is the sponsor of The Wall Street Journal’s Logistics Report.

Data-research group

Gartner Inc.

ranked Blue Yonder last year as the world’s third-largest provider in the supply-chain-management software market, based on 2019 revenue, behind

SAP SE

and

Oracle Corp.

Panasonic’s total acquisition cost of $7.1 billion includes $5.6 billion for the equity stake purchase and the cost of debt repayment.

Panasonic said the acquisition is expected to be completed by the end of 2021, subject to antitrust and other regulatory approvals.

Before the Panasonic deal, Blue Yonder had also planned to go public. The company said earlier this month that it had confidentially filed paperwork with the Securities and Exchange Commission for a proposed initial public offering.

Write to Kosaku Narioka at kosaku.narioka@wsj.com