It was purchased from the Shell Petrol Pump in the DHA Phase 1, the one near the Goal Masjid. And I know quite well which oil is a fake and which one is original 
If you go a decade back, even these Shell Oils were well blended with additives in proper labs using quality ingredients. But since long they are just stuck in money making business, and not caring at all about the customer. If you go outside Pakistan, Shell, Castrol and Caltex have excellent products still to offer to the customers.
Its just like none of the Petrol pumps here offer quality petrol/diesel and are mixing substandard fuel to make more money. Neither the companies nor the owners are interested in providing good quality fuel. If you dont agree import a new Merc Benz and run on the local Diesel available here. The company even cancels the warranty of their vehicles here-in due to the bad quality of fuel available.
The question is, can't they provide good products, or if they are not interested sincerely in doing so at all...
The choice is yours!