Adding a TOS late

Last year I created a collection of programs bound to macros to automate parts of my work. I shared these with my department and we have become reliant on them.

I was not assigned this duty, it is not in my job description, it was developed partially on company time but not to the detriment of other duties, and I do not believe I have been fairly compensated for it's use.

Do I have any legal standing to add a terms of service to this software to use in the event the company refuses to negotiate? My main goals would be to restrict the use of unauthorized copies and unauthorized modifications, and to open the door for turning the program into a subscription if other negotiations fail