Chris is a 25% partner in Marble Masonry LLC, which does not invest in real estate. On January 1, Chris's adjusted basis for his LLC interest is $500,000, and his at-risk amount is $450,000. His share of losses from Marble Masonry for the current year are $600,000, all of which is passive. Chris owns another investment that produced $150,000 of passive activity income during the year. (Assume Chris is a single taxpayer, there were no distributions or changes in liabilities during the year, and that the Marble Masonry loss is Chris's only loss for the year from any activity.) How much of Marble Masonry's losses may Chris deduct on his Form 1040?