You do not have to worry on this matter at all. In fact in the 70's, such a coup happened in Chennai. You would know the famous advertising agency in Chennai by name R K Swamy & Associates. Mr. R K Swamy was the branch manager of the Chennai branch of J Walter Thomson. It is now known as Hindustan Thomson Associates. Mr. Swamy on his own floated a company called R K Swamy & Associates and while pitching for business for JWT, was parallelly pitching for business for his own company. He got some good accounts. He then took some of his senior colleagues into confidence in the branch and they engineered one of the biggest coup in the Corporate world.
The lease of the building in which the JWT office was housed was expiring and so he spoke to the owner and took the lease of the building in the name of R K Swamy & Associates. One fine day, he made appointment orders for all the employees with an increase of salary by 50% and one level higher. He came to the office and called everyone for the meeting and told them that the building is now in the name of R K Swamy & associates. The telephones are in their name with new numbers. The furniture mostly in advertising agencies are hired and hence the furniture was theirs, since they changed the hirers name. He made an open offer in the group meeting and stated that they are all welcome to join his new advertising agency at a 50% higher salary and also one level higher. And in terms of advertising accounts, they have got prestigious accounts such BHEL, BEL, HMT and other such Public sector accounts and the revenue budgets are huge and the total revenue would plummet R K Swamy & associates to be one of the top 10 agencies in the country in the very first year. He spoke about a great career if all joined him. And those who desire to stay with JWT are welcome to leave the office.
All employees except 3 of them took the new offer. The three were asked to leave the office. All others were issued appointment letters and there was celebration with beer and lunch on the house. He then arranged to send telegrams in the name of each of the employee to JWT, HR department submitting their resignation and seeking immediate release.
The three employees went to a Post office and booked a trunk call to Mumbai, since there were no STD facility those days. After a wait of two hours, they got the call and informed the seniors in JWT as to what had happened.
The then CEO of JWT Mike Khanna rushed to Chennai. They consulted a lawyer and he was advised that nothing can be done, since the building lease had expired. The furniture was on rental and was now in the name of R K Swamy & Associates. All the papers and documents pertaining to JWT was neatly packed and kept aside and a telegram was sent to JWT asking them to pick up their property. The only thing available was the typewriters and the telex machine. But, they had some prestigious accounts such as Spencers, Ponds etc and they had to save them. So they immediately took a space in Hotel Connemara business centre and started servicing their clients. Emergency staff were flown in from other offices, till such time the vacancies were filled in.
Later after a couple of weeks, JWT went to court. But JWT lost the case, since the employees had complied with every clause of the terms of appointment and also had sent in cheques of one month notice period pay, which obviously was paid for by R K Swamy.
Though, unethically done so by R K Swamy, they were protected by law, since law has no emotions. So, as long as you are complying with the law, you don't have to worry.
Incidentally, R K Swamy's grandson is Arvind Swamy, who acted as hero in the famous Indian movie called Roja.
SInce you say the major billing is with the client, the company may go to the client and the client may decide to compensate them or fight it out in the court. It does not matter to you. You comply with the terms of appointment and be done with it. The company cannot sue you. And in case they do so, then most of the time, in such corporate coup, the employer fights the case in proxy. So be at peace.