Asking for rent payment without any written/verbal agreement

So may lupa sa tapat ng business establishment namin, walang nag ooccupy ng lupa so for the mean time pinark namin yung mga truck namin dun from the month of May upto now. Wala naman nagcleclaim nung lupa, wala naman nagsabi samin kung sino may ari. Tapos this month (October), biglang may nagpakilalang may-ari nung lupa (500sq.m) then humihingi bayad DAW ng renta. 10,000/month. Bayaran daw namin from May to October tapos ituloy tuloy na daw namin yung renta. Pwede po ba silang mag dedemand ng ganon kahit walang written or verbal agreement? Please po, we need ypur help kung sino man po makakatulong. Salamat