Telephone "voice", together meaning "distant voice". Credit for the invention of the electric telephone is frequently disputed. As with other influential inventions such as radio, television, the light bulb, and the computer, several inventors pioneered experimental work on "voice transmission over a wire" and improved on each other's ideas. New controversies over the issue still arise from time to time. Charles Bourseul, Antonio Meucci, Johann Philipp Reis, Alexander Graham Bell, and Elisha Gray, amongst others, have all been credited with the invention of the telephone. Alexander Graham Bell was the first to be awarded a patent for the electric telephone by
Disclosure of the invention under the European Patent Convention patent application as filed, consisting in an insufficient identification of the subject-matter claimed, cannot subsequently be cured without offending against Article 123(2) EPC which provides that the subject-matter content of a European patent application as filed may not be extended. An insufficiently clear and complete disclosure of the invention is a ground of opposition, and revocation. Although the European Patent Convention does not exclude the patenting of "revolutionary" inventions,<ref name="T 1329/07"> Decision T 1329/07 of the Technical Board of Appeal 3.4.02 of 11 November 2010, point 2.2.3</ref> The burden of proof generally lies upon an opponent to establish insufficiency of