 Set-top box recorders were not being sold in the U.S. for fear of unauthorized copying.However, personal computers with Blu-ray recorder drives were available.On January 1, 2010, Sony, in association with Panasonic, announced plans to increase the storage capacity on their Blu-ray Discs from 25 GB to 33.4 GB via a technology called i-MLSE (Maximum likelihood Sequence Estimation).