ALEXANDRIA, Va., Sept. 23 -- United States Patent no. 12,421,849, issued on Sept. 23, was assigned to REEVES WIRELINE TECHNOLOGIES Ltd. (Loughborough, Great Britain).

"Apparatus and method for signalling between downhole and uphole locations" was invented by Simon Christopher Ash (Newark, Great Britain) and Robert Ludeks (Loughborough, Great Britain).

According to the abstract* released by the U.S. Patent & Trademark Office: "An apparatus can include a downhole tool having a fluid outlet connectable to a fluid inlet to define a flow path via a hollow interior of the tool, and a valve member capable of opening and constricting or closing the flow path. The apparatus further includes pipe within which a part of the tool is located, the tool...