I work for employer A and got an offer from employer B and working with the law firm appointment by them to to file my H1B transfer. Later I got an another offer form employer C which I feel better than employer B so before they file my H1B I informed employer B that I am not going to proceed with them and closed it out. Now employer C told me the law firm they use for immigration and it is the same law firm used by employer B. In this case even though I stopped my processing before filing my H1b with employer B will the law firm share that information to employer C that I worked in parallel with another employer? Is it common for the law firms to share such information or they keep it confidential to the client.