What does the term "salting" as a union organizing tactic mean?

Salting is a union organizing tactic whereby the union pays an individual to apply for job within a targeted company and, once the job is obtained, to begin union organizing efforts. Salts—the term used for such individuals—may be overtly direct about their intentions or may use more subtle techniques. A salt's role is to gather information as a company insider and use it in the union organizing campaign. Some salting attempts are designed to target companies that deny employment to known union sympathizers. These individuals show up for interviews in union shirts, indicate union membership on job applications and make other overt pro-union statements and then report the employer to the National Labor Relations Board (NLRB) when they are not hired.

The NLRB has indicated that a protected individual under the National Labor Relations Act (NLRA) is one who is genuinely interested in employment with the employer and the NLRB has stated, "In our view submitting applications with no intention of seeking work but rather to generate meritless unfair labor practice charges is not protected activity."