Bitcoin miner Riot Platforms (RIOT.US) rose nearly 11% on Friday, currently up about 5%, as the company disclosed buying over 5,100 Bitcoins for $0.5 billion.
Riot stated that during the period from December 10 to December 12, it acquired 5,117 Bitcoins for about $0.51 billion, equivalent to an average price of $99,669, bringing its total Bitcoin holdings to 16,728.