Right YoYo

No, wrong... don't look for 2 question marks, look for one. Leslie says that when one company name derives from another, one should do a Prince and say "the [company] formerly known as [old name of company]". That's particularly important in this instance because the 'British Petroleum Co Ltd' is a different company. Another way 'round it is just to use the current name and forget about the old ones.