One year after announcing the deal, Western Digital has officially completed its acquisition of Viviti Technologies (formerly Hitachi GST) for $3.9 billion in cash and 25 million shares of WDC common stock valued totaling about $0.9 billion. The company plans to operate WD Technologies and HGST as two wholly owned subsidiaries, with separate brands and products, to meet the conditions of antitrust regulators.

"Similar to successful multi-brand models in other industries, the two subsidiaries will compete in the marketplace with separate brands and product lines while sharing common values of customer delight, value creation, consistent profitability and growth," Western Digital said in a prepared statement.

That's not the only condition Western Digital had to meet in order to get approval for the deal. Late last month, the company announced plans to divest certain assets to Toshiba, including manufacturing equipment and related IP, to comply with regulatory requirements. The move will enable Toshiba to enter the 3.5‐inch desktop and consumer electronics markets and expand its capacity in near-line storage for server applications.

At the time Western Digital also said that it has agreed, subject to completion of the divestiture transaction, to purchase Toshiba Storage Device Thailand (TSDT) and integrate the workforce into its operations in Thailand. TSDT is a hard drive manufacturing facility that has not yet resumed operations after last year's floods.

With the latest transaction announced yesterday, Hitachi now owns 10 percent of Western Digital's shares outstanding and has the right to appoint two individuals to the firm's board of directors.