Chief executives from four major technology companies will not attend a cybersecurity summit in California on Friday, despite being invited long ahead of time.

Instead, senior security staffers from the invited companies, Facebook, Google, Yahoo, and Microsoft, will go in their boss' places.

Apple chief executive Tim Cook did accept the invitation, however, along with others, notably Mastercard's Ajay Banga and Symantec's Michael Brown.

Speculation is rife as to why Marissa Mayer, Eric Schmidt and Larry Page, Satya Nadella, and Mark Zuckerberg declined the invitation to attend the cybersecurity summit at Stanford University.

The Obama administration is expected to announce executive action aimed at allowing private companies to share cyber-threat data with the government. It would end more than two years of deadlock between the White House and Congress, which had also locked horns over cyber-intelligence sharing. Congress was pushing for greater user data sharing capabilities, but Obama threatened to veto after privacy and civil liberties were not included .

It was a touch ironic, considering it was just a few months after a controversial law (dubbed CISPA) failed in the Senate that Edward Snowden's revelations came to light.

Bloomberg hinted that the reason why the tech executives are not turning up are in part due to a recent back-and-forth between the US government and their companies.

There's still a considerable level of friction after Apple and Google kicked back against government surveillance by installing device encryption with their mobile software. But the NSA scandal still has some executives less than pleased with the government.

But at the same time, the government wants to extend an olive branch, by helping to prevent cyberattacks against businesses. Those businesses, including Silicon Valley tech titans, want a free-flow of information between themselves and government in order to fend off attacks.

But in the wake of the wrongful allegations of the government's "direct access" to their systems in the wake of the PRISM program leak, technology companies don't want to be seen to be giving away any kind of user data to a surveillance-hungry government.

And all this executive action will probably bypass Congress entirely. That's fair as they were given the chance to build something, and failed at repeated attempts.

But the Obama administration, picking and choosing what it wants to run past Congress, said lawmakers are the ones who have to stop NSA spying -- not the government . A recent report from the government's privacy board said the Obama administration could stop some of the most egregious domestic spying without Congress, and by virtue rebuilding trust between the government and private industry.

And that's why Obama's tech legacy will likely be looked back on as a series of cyber-screwups.

It's not to say that Silicon Valley's leaders are actively steering clear of Friday's announcement. But it does say something about these proposals when they do decide to skip it for a regular day at the office instead.