In June, Google won a place in the Oxford English Dictionary, while "to google", with a lower case "g", was included last month in Merriam-Webster's Collegiate Dictionary, America's leading reference book.
But the California-based company is becoming concerned about trademark violation. A spokesman confirmed that it had sent the letters. "We think it's important to make the distinction between using the word Google to describe using Google to search the internet, and using the word Google to describe searching the internet. It has some serious trademark issues."