law: Companies Act, 1956
  Sec 51    -     Service
  
  of documents on company.
  A document may be served on a company or an officer thereof by
  
  sending it to the company or officer at the registered office of the company by
  
  post under a certificate of posting or by registered post, or by leaving it at
  
  its registered office :
  Provided  that where the securities are held in a
  
  depository, the records of the beneficial ownership may be served by such
  
  depository on the company by means of electronic mode or by delivery of
  
  floppies or discs.