Who almost invented the telephone?

It is said that who invented the telephone and fought a lawsuit. The two people who went to court were the famous inventors Edison and Bell. The focus of the debate is that Edison and other scientists did a lot of basic work for the invention of the telephone, and what Bell did was to turn a part in the telephone receiver by a quarter. The court finally ruled. Bell's small rotation changed the intensity of current, which played a decisive role in creation and made the telephone really applied to social life, so the telephone was invented by Bell. Edison regretted the judge's decision. Although he is a universally recognized inventor, he missed the invention of the telephone because he didn't take a step forward.