Shares of Nuance Communications, which develops speech recognition technology, rose 18.37 percent to $53.93 on April 12. The surge in quotations occurred after Microsoft announced its purchase of the company. The amount of the deal, taking into account net debt Nuance will be 19.7 billion. Microsoft will pay $56 per security.

Nuance specializes in artificial intelligence and voice recognition technologies. Its developments were used, among others, in the creation of the voice assistant Siri for Apple.

Nuance will allow Microsoft to expand its capabilities in voice software. The company's technology will also be used in Microsoft's cloud-based healthcare products, for example, to develop solutions that will free doctors from having to take notes during appointments.