Land allotted for the establishment of starting a factory - What the Company has done on the basis of the said order is to register it - Later revocation of the said sanction - Company claiming promissory estoppel filed writ petition . Necessary ingredients for applying the principle- Petitioner should have changed its position to its detriment acting upon the promise. [M/s. Janahta Tin Factory vs State . OP.No. 2377 of 1992. Dated 2nd November, 2000. M.R.Hariharan Nair (J)]