One of the largest shareholders in the company sent Wausau Paper's Board Chairman, Tom Howatt, a letter saying they were upset Wausau Paper made the announcement without telling them.
In the letter, they also said Wausau Paper has a history of making poor decisions.
Wausau Paper officials told us they have no comment, but since the announcement of the sale, there's also a lot of concern about the people who could be impacted.
That includes Rhinelander Mayor Dick Johns who worked at the Wausau Paper Mill in Rhinelander for 40 years, before moving into government.
"The wages over there are probably as good as anywhere else in the paper industry and it's a big asset to the community," said Johns.
Johns said he was surprised by an announcement Friday afternoon, that Wausau Paper plans to sell its mills in Mosinee, Rhinelander and one in Minnesota.
But Johns said he hasn't been able to contact anyone from Wausau Paper to talk about it.
"We only know what's going on, what the community knows, in the case of the Rhinelander area it affects a lot of people, retired as well as those working over there," said Johns.
More than 500 people work at the Rhinelander mill.
Johns worries losing them will hurt the local economy.
Newsline Nine's Dan Griffin talked to some business owners who said it's still too early to know.
"If the mill is sold of course, it'll be some new changes, different ownership, I don't think we're at the point where anyone's talking about closing it," said Rhinelander Pub and Cafe Owner, Mark Gutteter.
Gutteter said his business been around more than 100 years.
He said he's optimistic his business can survive any changes.
"We have experience in seeing ups and down in the business cycle," said Gutteter.
But no matter what, city and business leaders said the potential of hundreds of employees losing their jobs is unsettling.
Wausau Paper has said following the sale of the mills in our area, the company plans to focus on tissue operations in Ohio and Kentucky.