In answer to the original question, the answer cannot be direct, If we talk about the original concept of privitisation the answer is yes all companies have had some sort of industrial action. If we then talk about since franchises have changed hands or new open access operators started then the answer is no.
Take the company i work on, under National Express ownership i can remember going on strike at least three times with at least another 4 threats of industrial action being averted some at the eleventh hour. Also in 2005-06 Conductors refused to work their booked Sundays over Christmas as the company decided to pay one grade but none of the others, so all the Conductors took time off whilst the Managers had to come in and work on both Christams eve and New years eve which that year fell on Sunday.
Under ownership of TfL we have had no strikes or industrial action to date, however we have had one ballot that was overwhelmingly supported (76% turnout getting a 90% yes vote) saw the company sit back round the table and dispute was averted.
I cant speak for other companies tbh as i dont know their T&Cs however it does seem that it all depends on local issues. When First group ran services under the GE banner industrial relations were good, when NEG took over they wanted hamonistation based on all the worst faceits of the three merged groups, the union sat around the table for 5 years before deciding to call it a day and keep all the staff on their former companys terms & Conditions.
Then you look at Arriva and you can see that industrial relations have soured so much that industrial action is always on the cards. Things must be bad with Arriva if the drivers are taking industrial action.
When i speak to my former colleagues that are now on London Midland, they tell me things were better under Silverlink/NEG ownership.
Some of the newer companies seem to have a more hands on approach with the staff, rather then the using the stick all the time.
It is a very good question though raise by the OP.
