SAN FRANCISCO (KGO) -- There are big changes coming in the tech world as a number of companies have delayed their official reopening, and the list of companies requiring vaccinations continues to grow.
Google and Facebook announced they will require their employees to be vaccinated before coming back to the office.
Experts say the move, coupled with previous state and federal vaccination mandates, could influence other companies to move in the same direction.
Twitter announced the closing of their offices in San Francisco and New York Wednesday after those locations had just reopened at 50 percent capacity two weeks ago. The major changes come as COVID-19 cases are again on the rise.
"Most of the smart companies are deciding to leave their people at home as long as they can," says tech analyst Rob Enderle with Enderle Group. He says those start dates are likely to be pushed back even more going forward with the threat of the Delta variant, and most workers not in a rush to give up working from home to begin with.
VIDEO: Why did the CDC update its mask guidance? Some breakthrough cases may be infectious, data shows
The move by Google and Facebook to require their thousands of workers to get vaccinated is not a shock to doctors.
"People just need to take a step back and realize vaccine mandates are nothing new," says ABC7 News Vaccine Team member Dr. Alok Patel.
While the move to require vaccinations is a big one, experts say it's not the most popular one among companies right now.
"As we've been collecting data from all the companies that we've been working with, we're finding that less than 10% of companies are currently planning on requiring that employees show proof of vaccination before returning to the workplace," says Brian Kropp who is Chief of Research at Gartner's human resources practice.
VACCINE TRACKER: Here's how CA is doing, when you can get a coronavirus vaccine
But experts also say that with the government allowing companies to put these requirements in place, there is now a threat of a different kind of lawsuit.
"If somebody gets sick on site or dies on site as a result of the company allowing unvaccinated people on campus, those are lawsuits we're going to see relatively prevalent before the end of the year," says Enderle.
Kropp says we've seen the "first cracks in the dam," so-to-speak, in requiring vaccinations, but it's unclear if this move by tech companies will impact the market as a whole.
"If we see a big manufacturing company, or retailer perhaps, say they are going to require vaccination, that's when we know the mindset has really shifted."
Having trouble loading the tracker above? Click here to open it in a new window. RELATED STORIES & VIDEOS: