I believe it's because PG is opposed to the idea and HN has inherited that philosophy. It's worth pointing out that Thomas Edison, Edwin Land (Polaroid), Georg

I believe it's because PG is opposed to the idea and HN has inherited that philosophy. It's worth pointing out that Thomas Edison, Edwin Land (Polaroid), George Eastman (Kodak), Nicola Tesla (lots!), and Walt Disney were all single founders.