Doubt On Contract Labour-Pls Clarify

There exists a contract between employees and contractor for staying 4 years with them(contractor).The contractor has deputed those employees as trainees to the principal employer.Once the trainees completes their training period with the principal employer they will be obsorbed by the principal employer.Till that time they will be paid by the contractor and they will be in the rolls of contractor.
Within a year,due to slow down in projects with the principal employer,the principal employer could not train its trainees further as a cost cutting measure and told the contractor to take all the trainees back by giving 1 month of notice period.And the contarctor also issued notices to all its employees who were deputed to the principal employer.
And my Question is:Is there any possibility for the employees(Trainees) to proceed legally against the principal employer?
Whether this issue comes under Contract labour act or Industrail disputes act or Apprenticeship act?

In the first case, contractor will supply manpower as per the provisions of contract labour (R&A) act. i.e., he will supply unskilled, semi-skilled and skilled manpower. There is no question of a contractor supplying trainees to the org.
Secondly, he has to also ensure that all statutory payments are made for the staff on his rolls and deployed at any place.
Third, principal employer is responsible for any default committed by the contractor.
Hence in this particular case, the staff can approach the labour court for justice.
Sai

The labour supplied contractor will be treated as your workmen if u didnot took registration under the act.
Secondly if you are asking abput apprentice Act, whether you took permission from apprentice advisor before taking them in trainee.
Whatever the employer has done by giving one moth notice is totally a example of ignorance of law having no excuse.
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