The applicant referred to in a patent application can, therefore, be one or more people or companies. The right to be mentioned as the inventor, on the other hand, can never be transferred.
For an employee who comes up with an invention that falls within the employer's operational area, there are certain limitations to the inventor's right to the invention. The limitations are dependent on how close the connection is between the employee's work tasks and the invention.
If you are employed by a company and come up with an invention, you should find out what applies for your particular invention before you file a patent application.