Acting National Labor Relations Board (NLRB) General Counsel Lafe Solomon is noticing a trend.

According to Solomon, there has been an increase in NLRB cases involving social media since 2010. That was the same year the board issued a catalytic complaint against the ambulance service American Medical Response of Connecticut over its firing of an employee who criticized the company’s management on her Facebook page. The case settled the next year with the company agreeing not to discipline workers for discussing their working conditions on social media.

“The case went viral,” Solomon said recently at a conference. “Because of the exposure of that case, we’ve had over 100 charges filed with us.”

Many of the charges fall into two categories: those challenging the discharge of employees and those disputing companies’ social media policies, Solomon said.

After the landmark American Medical Response case, Solomon issued three reports on social media cases and policies with the goal of providing employers with guidance about how to craft policies that aren’t too broad. The NLRB also issued decisions related to social media, which could be nullified as the D.C. Circuit recently ruled that President Obama’s recess appointments—including the appointments of Sharon Block, Richard Griffin and Terence Flynn to the NLRB—are invalid. The Obama administration plans to appeal the decision to the Supreme Court.

For more social media-related coverage from InsideCounsel, read:

Tackling social media challenges

Labor: Avoiding a viral termination

How to enforce ownership of social media accounts

Regulating employee behavior on social media: The limits of corporate policy

5 labor and employment issues to watch in 2013

E-discovery: Preservation of social media, what every company needs to know