Dear Mr. Keshav Korgaonkar,
You can refer the Employee's Provident Fund Scheme, 1952, Sub-section (f) of Section 2, which narrates "Excluded Employee" as
i) an employee who, having been a member of the fund, with drew the full amount of his accumulations in the fund
ii) an employee whose pay at the time he is becoming a member of the fund exceeds 6500 per month and
iii) an apprentice.
In case an employer wants to keep an employee out of PF -he needs to ensure that he is not an existing member in PF and drawing more than 6,500-00 (Basic+DA) at the time joining. Hence, need to collect Form-11 from the employee if the employer wants to exclude on the above ground to ensure non membership in PF.
Need to remind you, once a member in PF will continue to be a member irrespective of quantum of salary.
Regards
Pratap