An Intel spokeswoman had no additional comment.

Update: On Thursday, an Intel spokeswoman said Mainz has taken a job at another as-yet-unnamed publicly held company. Jim Douglas, who had been senior vice president of marketing, has been named interim leader.

Wind River, which announced new products in November, remains a critical part of Intel’s strategy, she added.

The personnel shift, which happened in the dead-news week between Christmas and New Years, was disclosed internally, but not announced. And it prompted some head scratching given that the real-time operating systems that Wind River focuses on are critical for the Internet of things.

IoT is tech-speak for global network of connected devices that talk to each other, and to us, including sharing data about weather, traffic patterns, and kitchen appliances. Many of these devices must react in real-time, which Intel’s Wind River unit enabled through so-called embedded operating systems.

These embedded operating systems that are tailored for the task at hand, as opposed to the more generalized operating systems that run PCs and laptops.

MORE: Intel completes $16.7 billion acquisition of Altera.

Intel bought Wind River for $884 million in 2009 and made it a wholly owned subsidiary reporting into Renee James, who was then head of Intel’s Software and Services Group. James was subsequently named Intel (INTC) president but announced this summer her intention to leave in January. The executive departures may signal that Intel chief executive Brian Krzanich is consolidating control. Or not. As noted Intel is mum.

In 2004, Wind River scored a huge public relations coup when NASA’s Jet Propulsion Lab used its VxWorks operating system in its successful Mars Rover expedition.

WATCH: Renee James is out as Intel president.

Intel watchers have wondered lately about what was going on with Wind River under Intel. In September, it reportedly laid off a number of experienced engineers, including many who had worked on VxWorks.

Mainz, after stints at Mercury Interactive (now part of HP), joined Wind River in 2005 as vice president of worldwide operations and was named chief operating officer three years later. Then, in 2013, he was tapped as president when Ken Klein, who had held that post, left to become chief executive of Tintri.

While Intel didn’t provide additional detail, a source close to Wind River, said this appears to be part of an Intel plan to bring once semi-independent business units more closely into the corporate fold.

One big issue may have been that Wind River, as a maker of operating systems, had to support more than Intel’s own chipsets. That may have caused strains with the mothership which, after all, is still primarily a chip maker with a vested interest in promoting the use of its own silicon and not that of ARM or AMD, for example.

Wind River helped entrench Intel deeper into the embedded market, especially among telecom carriers that need to use specialized chips with embedded operating systems in their gear, said Patrick Moorhead, founder and president of Moor Insights & Strategy, an Austin, Texas-based research firm.

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On the other hand, Wind River also faces more competition in the IoT era “and its long-term success will be determined by how well it does there,” Moorhead added. And, while Wind River continued to support non-Intel chips, it was devoting more of its resources proportionally to support the home-team technology, Moorhead added.

Note: This story was updated at 9:11 a.m. on December 31, with Intel’s comment and news of Mainz’s new job.