The Short Version
This claim is false. The $50 million invested in Terrana Biosciences came from Flagship Pioneering, a biotech venture firm — not from Bill Gates personally or the Gates Foundation. The Gates Foundation's own grants database shows no funding to Terrana. Snopes investigated this exact rumor and found no evidence of a Gates connection, and Flagship Pioneering's spokesperson explicitly denied it. The claim originated from unsourced social media posts that misattributed the funding source.