Lazarus Laboratories

Lazarus Laboratories were the laboratories of Richard Lazarus located in Southwark. Lazarus' research was funded by Harold Saxon, and Lazarus Laboratories's logo was very similar to the insignia on the Master's ring. The Tenth Doctor and Martha Jones attended a reception there, when Professor Lazarus was showing his machine. (TV: The Lazarus Experiment)

As Harold Saxon, the Master had the company logo on his ring, completed with circular Gallifreyan inside the disks, (TV: Last of the Time Lords) which would later be used to resurrect him. (TV: The End of Time)